http://farm6.static.flickr.com/5212/5383770489_73e4f921f7_z.jpg

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All above photos copyright Ministry of Transport on flickr.

Land Transport Authority Contract 151A

22 sets 6-car trains for SMRT Trains North-South and East-West Line.

Tender awarded to:
Consortium of
Kawasaki Heavy Industries・Kawasaki Heavy Industries Rolling Stock Company (川崎重工業車両カンパニー) and,
CSR Qingdao Sifang Locomotive & Rolling Stock Co., Ltd. (南车青岛四方机车车辆).

Responsibilities:
Kawasaki: Sub-tender and procurement of propulsion and electric components, technological transfer to CSR for construction of train bodywork. Testing of trains in Singapore.
CSR: Assembly of tendered components, construction of train bodywork, testing and commissioning of trains.

Main specifications:

Formation: 6-car (DT-M1-M2-M2-M1-DT)
Seating: DT: 50, M1: 50, M2: 48
Handgrips: 62 per car
Length: 23830 mm (Motor cars 22800 mm)
Width:3200 mm
Height: 3690 mm
Gauge: 1435 mm
Highest operating speed: 80 km/h
Body: Aluminium
Acceleration: 3.6 km/h/s (1.0 m/s)
Deceleration: Maximum Service -4.3 km/h/s (1.2 m/s), Emergency -4.7 km/h/s (1.3 m/s)
Supply: 750 VDC third rail
Bogie: Axlebox-supported axle type (monolink), bolsterless air spring bogie.
Propulsion: Fuji Electric (富士電機) VVVF Inverter (IGBT Semiconductor Controlled)
Motor: Fuji Electric (富士電機) Three Phrase AC
Static Inverter: Fuji Electric (富士電機)
Master Control type: 4 Power, 3 Brake + EMG notches

SMRT Numbering system: Series 500

Status:

Delivered:
501F: 3501 - 1501 - 2501 - 2502 - 1502 - 3502
503F: 3503 - 1503 - 2503 - 2504 - 1504 - 3504
505F: 3505 - 1505 - 2505 - 2506 - 1506 - 3506
507F: 3507 - 1507 - 2507 - 2508 - 1508 - 3508
509F: 3509 - 1509 - 2509 - 2510 - 1510 - 3510
511F: 3511 - 1511 - 2511 - 2512 - 1512 - 3512
513F: 3513 - 1513 - 2513 - 2514 - 1514 - 3514
515F: 3515 - 1515 - 2515 - 2516 - 1516 - 3516
517F: 3517 - 1517 - 2517 - 2518 - 1518 - 3518
519F: 3519 - 1519 - 2519 - 2520 - 1520 - 3520
521F: 3521 - 1521 - 2521 - 2522 - 1522 - 3522
523F: 3523 - 1523 - 2523 - 2524 - 1524 - 3524
525F: 3525 - 1525 - 2525 - 2526 - 1526 - 3526
527F: 3527 - 1527 - 2527 - 2528 - 1528 - 3528
529F: 3529 - 1529 - 2529 - 2530 - 1530 - 3530
531F: 3531 - 1531 - 2531 - 2532 - 1532 - 3532

Not delivered:
533F: 3533 - 1533 - 2533 - 2534 - 1534 - 3534
535F: 3535 - 1535 - 2535 - 2536 - 1536 - 3536
537F: 3537 - 1537 - 2537 - 2538 - 1538 - 3538
539F: 3539 - 1539 - 2539 - 2540 - 1540 - 3540
541F: 3541 - 1541 - 2541 - 2542 - 1542 - 3542
543F: 3543 - 1543 - 2543 - 2544 - 1544 - 3544

Improvements:

Maximum Service brake value upped from -3.6 km/h/s (1.0 m/s). Stronger service brake value due to revision of passenger, hence overall train weight.

LED lighting for cab identification light (above cab emergency door) and train identification number.

Unofficial: 501F: Change of main control stick from previous stock. A design similar to a simple L handle, still right-justified on control board.

Unofficial: 501F: Change of speed code lights format from previous stock.

As the development time is short, the inverter system and motor are closely related to those used on the C751B. Component specifications for the C751B is listed below.

VVVF Inverter: Stator Flux Vector Control, 415 kVA x2 per motor car
Three Phrase AC Motor: MLR109 (140 kW ea)
SIV: VVVF Inverter, with battery charger, 80 kVA + 16 kW

Originally Post 1:

*Thread copied from HKiTalk/SPT. I posted the thread on 25th July 2010 for discussion in that forum.*

This thread is open about one year from the expected date of delivery for the new rolling stock for the East West and North South Line, in conjunction with the Jurong East Modification Project (JEMP)

At this point, there are no accurate sources suggesting the design nor the components for the C151A. However, I find it appropriate to discuss about technologies and designs that may be incorporated onto the new trains.

Since the last rolling stock in 2000 (Series 300/C751B), technology on trains have advanced, both on safety and passenger comfort. Some comparisons of the basic technology used on the previous trains.

Bodywork:
All units: Aluminium-alloy double skinned (two layers of aluminium-alloy plating)
Information about the bodywork can be found from old MRTC publications. The Siemens bodywork is also made to Aluminium, possibly a standard conformation.

Traction Controller:
C151: 4-Quadrant GTO Chopper (Electric Chopper)
C651: VVVF Inverter (GTO)
C751B: VVVF Inverter (IGBT)

Motor:
C151: DC, 135 kW
C651: AC three-phrase cage, 140 kW
C751B: AC three-phrase cage, 140 kW

Drive type:
All: WN (Westinghouse-Natal) Drive

Bogies:
All: Bolsterless type

Power configuration:
All: 4M2T (M:T = 2:1)

Regeneration (electric braking):
C151: down to 8 km/h
C651: down to 3 km/h
C751B: down to 6 km/h

Regeneration cut is defined as electric regeneration transition to dynamic braking (friction). Motor efficiency drops as speed of rotation decreases, it will reach a point where further regeneration will not slow the train down as fast as rated, hence electric will be cut and friction brake applied. Further will be discussed later.

The following are my expectations (hereby speculations) of the new C151A. Description of individual parts will be explained.

Bodywork: Stainless-steel
Traction controller: VVVF Inverter (IGBT)
Motor: 140 to 190 kW
Drive type: WN Drive
Bogies: Bolsterless
Power configuration: 4M2T/3M3T (non 2-unit EMU)
Regeneration: Full electric brake (to 0 km/h)

I have chosen the bodywork to be SS made largely for the advancement in reinforcing SS bodies. In the past SS is not as reliable as aluminium alloy (although aluminium itself is very soft as a metal!), but as technology advanced and SS trains are more reliable to produce and economical to run.

Traction controller is the standard VVVF Inverter, IGBT controlled type. Lightweight and compact for usage on metro trains, energy saving and fast (current and voltage control).

Motor I would range it between 140 and 190 kW, as less powerful motors are needed now to reach acceleration of 3.6 km/h/s (Singapore Metro standard). However if the train is designed for redundancy purpose (one or two motors resting during normal operations) then 190 kW is necessary. Do not that redundancy measures are customized and does not come as a standard.

Drive and power configuration would likely remain the same. For my guess on individual motors of 190 kW output without redundancy design, 3M3T is also possible (however not possible to have 2-unit EMU in this case). For all other popular outputs (140 to 180 kW) 4M2T would be a favorable choice.

Bogies would likely remain as the bolsterless bogies. These bogies are good in low center-of-gravity (CG) but bad in damping and higher speeds. The addition of a yaw damper would improve curve damping and raising passenger comfort.

Now it comes to regeneration. Full electric brake, guess many have not heard of it before. Its not a new thing, and it also can be incoporated into all existing trains (including the C151)!

Full electric brake would mean regeneration braking to about 8 to 3 km/h, then either a phrase control to 0 Hz (Mitsubishi inverters) or current excitation (Hitachi inverters). When a motor accelerates (having an electric load), the field excites the armature, turning the armature and then the gears then the wheels. Regeneration braking is used by reversing the armature current poles, hence torque is developed, electric resistance is converted to kinetic resistance to slow the train down. Just like stirring a drink, then stopping the spoon. The liquid will slow down until it reaches a very slow speed, but how to stop it completely?

Mitsubishi and Hitachi have their own methods. Mitsubishi chooses to manufacture their inverters to control the phrase (three in AC) to 0 Hz, able to completely stop the motor without using much energy.

Hitachi uses current excitation to flow against the amarture movement, just like stirring your spoon backwards of the flow, to completely stop the liquid. During this course, there will be an iconic 'booo' sound, and this is what separates the Hitachi from the Mitsubishi inverters. Attentive train fans in Japan can identify inverter types just like this, among many other skills.

Full electric brake does not mean the elimination of friction brakes; both types of brakes must be present for safety and redundancy purpose. One example to show why.

Recently I have took several C151 trains, and found that certain motor carriages have regeneration loss or regeneration off, either mechanical or electrical faults. Most likely this is due to the running conditions of the DC motors. When regeneration loss/off occurs, air brakes (friction/dynamic) must be used and coordinated with other carriages still having regeneration braking to stop the train. I could remember taking 045, with 1045 on emergency braking (friction only) and 2045 with regeneration working well. Soon enough, 1045 is having flat wheel problems (worn out surfaces) and still persisting at time of writing.

Regenerative brake not only slows the train down with little wear on brakes, but also feeds back power to the lines, as the motor works as a generator during the process. C151 have the largest current draw, and also the largest regenerative current, which can peak up to 400+ ampere. However, if the line (section) has no other train/device drawing power, regeneration will not work and likely regenerative braking will not be used.

At heavy loads with high kinetic energy, regeneration braking is not enough to stop the train at rated deceleration force (about -3.88 km/h/s for C151), hence dynamic braking is used together with regeneration braking. This is the same for raining (moist rail) and emergency braking (full dynamic).

The good points of having full electric brake is not about sights nor sounds. Basically, it would be;
less wear and tear on dynamic braking (less friction brake usage),
better passenger comfort (no transition of regeneration to dynamic resulting in jerking)
larger range of regenerative braking means more electric regeneration (for frequent acceleration and current draw),
and high adhesiveness for better control and certain degree of prevention from overruns.

After so much of hardware, the talk on need for software upgrade is there. With new trains, train drivers (TO) should be placed longer in the simulator and on the rails, with more emphasis on CM mode to let them accustom to driving and negotiating curves at comfortable speeds and stopping in time. Recent PSD works have finally placed TOs on CM modes more often again, and with more training they can stop the train in a comfortable, safe and accurate manner.

Do post your thoughts on the C151A as more news and expectations roll in!

Originally Post 2:
Some updates and technical analysis that was observed after this thread went up.

Looking at the electric current (ampere) meter of the Series 0/C151, the initial current draw during acceleration is about 480 A, after the 'second gear' (where there is a boo-booo~ sound) the current spikes to 500-520 A, then slowly decreases back to 450~ A. During B2 braking, regenerating current was about 380 A.

Compared to VVVF Inverter trains (about 100 to 200 A draw per motor), the electric chopper is indeed a high current draw vehicle!

Based on advancement of Japanese trains, electric train controllers can be divided into the following types;

-Resistive control, where resistors vary the current supplied to the motors.

-Chopper control, where high speed on-off control is used, first using basic field control (akin to magnetic, but itself divided into many types), then in the 80s, electric chopper where a semiconductor element is used to control the chopping action, hereby increasing the efficiency and electric control. The most successful of the electric chopper is the 4-Quadrant GTO Chopper, where '4 Quadrant' means control of 'forward mode forward movement and forward brake, backward mode forward movement and backward brake', in basic, the controller can be used to control the motor in two directions with respective braking capabilities. A GTO (Gate Turn-off thyristor) semiconductor is used.

-VVVF Inverter, possibly the most advanced as of now, where VVVF means Variable-Voltage Variable-Frequency, and in basic sense, controls current fed to motors using a variable value of voltage and frequency. Similarly, semiconductors are used, first the GTO, then the IGBT (Insulated Gate Bi-polar Transistor). IGBT replaced the GTO mainly because of higher speed control capabilities and lesser electric current draw.

I find that the explaination on bolsterless bogies is insufficient in the previous post. Bolsterless bogies means, bogies without bolster (duh!). Bolster in this railway sense means a bar/bridge horizontally across a bogie, linking and transferring forces from the bogie to the carriage and vice-versa. The bolster bogie also have a bolster anchor, with a yaw damper, to provide a damping link between the bogie and the bolster bar. Hence the 'cake', or sequence, from the top is carriage > bolster link > bolster bar > air bags and bolster anchor/yaw damper > bogie.

A bolsterless bogie means there are no bolster, the carriage rests directly on the air bags itself, with the air bags suffering 'deformation' (as much as 100 mm) as the bogie is turned when the train negotiates a curve. A center thrust link acts as the main force transfer element. The sequence of linkage is carriage > air bags and center link > bogie. A good deal of simplification, isn't it?

The main drawback of the bolsterless bogie is the transfer of lateral forces to the bogies from the carriage. I am sure many folks remember the JR West Amagasaki accident in 2005, when a JRW Series 207 commuter train derailed and hit a apartment building at a R300 curve, causing 107 deaths. That train uses the bolsterless bogie (with yaw dampers on both side), as the high speed of curve G-forces and emergency brake forces acted on the carriage, the carriage tilted so much that it deformed the air bags, broke the yaw dampers and finally doomed the train. Although we do not travel as fast as 120 km/h, but remember the uncomfortable sideway banging sensations on a C151 when it negotiates tight R300 curves at places like Clementi? A little faster, and derailment is what may happen.

There are several companies which run a through service in Tokyo, very famous for their anti-bolsterless bogie ideals. They are none other than the Toei Asakusa Line (都営浅草線) centered, Keikyu (京急), Keisei (京成) and Hokuso (北総) /Chiba New Town (千葉ニュータウン) Railway companies (five different companies in fact). Hokuso and Chiba New Town are operator and railway owner respectively. Cutting it short, legend has it that Keikyu does not accept bolsterless bogies from the days it started out, and bends on using conventional bolster bogies, combined with a motorized control car (front car), for better control and stability properties.

An accident in 1997 involving a Keikyu train (Type 1500) with a landslide proved its policy correct, the train did not derail much (as compared to examples from JR and other similar accidents) and damage was kept to a minimal. Hence motorized control cars did prove its value, together with tough bogies.

Going on, compared to JR East which runs parallel route with it from Shinagawa to Yokohama, Keikyu is able to speed through most of the sectors at 120 km/h, while JR East trains, having low acceleration and bolsterless bogies (for the E231), lose out most of the time. Keikyu also 'bans' (hereby disallow) bolsterless bogie and non-motor front car trains from entering its lines. Such is the strict rules that ensures both speed and reliability of its operations that it has garnered attention from railway industry players all around Japan.

No doubt the bolsterless bogie has advanced in technology over the years; from the 1980s when the first bolsterless bogie was fitted on the Tokyo Metro Series 8000 (then Eidan Subway/営団メトロ, now Tokyo Metro) and problems about the stability of the trains running above 100 km/h into the Tokyu Denentoshi (東急田園都市線), in fact, that is what the Tokyu train drivers had complained about! Now, bolsterless bogies are used on the latest Keisei Skyliner (2nd Generation AE, top speed 160 km/h, highest in Japan for standard gauge/trunk line), many versions of Shinkansen ('Bullet') and Commuter/Subway trains.

Another thing gone (for good) are Chervon springs for the train wheels (two layer-like things that sandwiches the wheel hub). Remember the 'pssh-pssh' sound that wheels and rails make when negotiating a curved section? With the Chervon springs this kind of sound is much louder, due to the strong 'holding' force the springs have on the wheels to prevent it from moving out of alignment. As technology advances (again), this is replaced by conventional hydraulic suspension, and from the Series 300/C751B, you don't hear the pssh-pssh sound that often anymore. Ah, advancement of technology!

In my next post (when I can find time again), I shall share bits of thoughts I have on the new signaling system. Stay tuned, heh~!

Hmm, Interesting :D

a great deal of technical contribution here. I didnt know most of the terminology till you mentioned :lol:

I think trains are likely to remain in its 4M2T configuration since there are no significant benefits to 3M3T. the savings from one less motor car is negated by three higher powered motors.

full electric braking should mean a more pleasant journey with less screeching. any idea what is the regeneration of Alstom C751As and C830 stocks? I bet they are much higher seeing how noisy they are. KHI and Bombardier (hopefully) will fare better here.

speed isnt going to be a huge consideration on mainline stock. the service speed limit is 80km/h and singapore is obsessed with safety. bolsterless bogies should remain the mainstay here.

The Alstom Metropolis (both the Series 70000/C751A and Series 8000/C830) has the highest regeneration cut, about 10 to 15 km/h (based on visual observation). I am not sure of the exact programming, but this cut of regeneration brake is similar to older trains where effective regeneration wears out at high speed (some as high as 45 km/h) and friction brake is used thereafter.

Of course, I do not suppose the same happens to the Metropolis, but rather the demand for high stopping accuracy that requires more friction braking than regenerative as it is more 'accurate' and easier to control.

Comparing the two Metropolis types in Singapore...

Bodywork:
All: Aluminium (Welded)

Power Supply:
C751A: 1500 VAC overhead
C830: 750 VDC third rail

Traction Controller:
All: VVVF Inverter (IGBT/Alstom ONIX)

Motor:
All: AC, three-phrase cage, 150 kW
Checking out on Wikipedia, the C830 motor output is noted to be of 400 kW each. I don't know whether to laugh or cry, and I wonder since when are we running TGV systems.

Drive type:
All: WN (Westinghouse-Natal) Drive

Bogies:
All: Bolsterless type

Power configuration:
C751A: 4M2T (M:T 2:1)
C830: 2M1T (M:T 2:1)

Regeneration (electric braking):
All: Down to about 10-15 km/h

Components of the C830 include VVVF Inverters on each motor car, forming a 1C4M control-motor configuration. SIV/APU, the Auxiliary Power Unit that provides power to on-board electronics, is located at the trailer car, so is the air compressor (for friction brake and air-conditioning). Air-conditioning units are present on all cars.

Pardon me for any errors in the technical of the Metropolis; I specialise in Japanese systems and frankly, sometimes European technology can 'freak' me out, especially having to deal with several languages as a start...

Is there any YouTube video you could pull out off from Japan that the C151A will roughly sound like?

Maybe like the Tokyo Metro 10000/15000/16000? (I know it's Hitachi, just stating an example).

Is there any YouTube video you could pull out off from Japan that the C151A will roughly sound like?

Maybe like the Tokyo Metro 10000/15000/16000? (I know it's Hitachi, just stating an example).

But C151A is made in china.

But C151A is made in china.
Its Chinese made but using Japanese technology so there MUST be a stock (likely to be Japan since most Chinese subway trains are Alstom, Siemens , Bombardier) whose specs are similar.

subscribe :D

Some explanation on the Westinghouse ATC system.

In the system that Westinghouse Brake and Signal Company developed for MRTC, there are several terms of 'Automatic', like;

Automatic Train Control, ATC
Automatic Train Operation, ATO
Automatic Train Protection, ATP
Automatic Train Supervision, ATS --> A potentially misleading term to a Japan railway system student like myself.

The most important of all and to understand just how the system works (and how to push it to the limit) is the first two, ATC and ATO.

Very simple, just look at the first two. Others are just part of them.

The Westinghouse ATC (hereby W-ATC) consists of two major components, Maximum Safe Speed (MSS) and Maximum Target Speed (MTS). The highest MSS is 80 km/h, lowest 0 km/h. MSS is not the speed displayed at the cab side (next to the speedometer), what is displayed is the MTS. MTS consists of 80, 65, 45 and 0 km/h. Other MTS that are not used with ATO are 35 and 20 km/h.

That is according to the original Westinghouse specifications on ATP; a recent LTA publication indicates MSS and MTS as different values, nonetheless, the differences are minimal.

For every zone, the MSS and MTS will work together to 'protect' the train from overspeeding and hitting the train in front. This is how it works. Note that 'program' means operation under ATO, there are two, 'flatout' and 'coast', more will be explained below.

Code 6, Zone 4: MSS is 80, MTS is 80. Train will 'motor' to 80 km/h and maintain that speed. If the program is in 'flatout', the train will keep on applying power to keep to 80 km/h as close as possible. In 'coast', it would coast with sufficient speed to reach the next station, motoring and braking as necessary.

Code 5, Zone 3: MSS is 80, MTS is 65. On Auto: Train will start braking to 65 km/h and maintain speed there.
You could still go at 80 km/h, but you must reach 65 km/h before hitting the next ATP zone. Failure to do so will trigger the emergency brake. Emergency stop from 80 km/h here would gurantee a complete stop in ideal conditions within zone 0 (see below).

Code 4: MSS is 65, MTS is 65. This is for a train accelerating; the train will 'motor' to 65 km/h and maintain speed.

Code 3, Zone 2: MSS is 65 km/h, MTS is 45 km/h. On Auto: Train will start to brake to 45 km/h.
You could still go at 65 km/h, but you must reach 45 km/h before hitting the next ATP zone. Failure to do so will trigger the emergency brake. Emergency stop from 65 km/h here would gurantee a complete stop in ideal conditions within zone 0 (see below).

Code 2: MSS is 45, MTS is 45. Same terminology as Code 4.

Code 1, Zone 1: MSS is 45 km/h, MTS is 0 km/h. On Auto: Train will now brake to 0 km/h.
There is an exception to this zone, called the station stop command. If the train receives a station stop command, means the station is clear, it will follow its stopping profile and enter the station, ignoring this code. This is true when the ATP zone before and after the station is clear of train.
You could still go at 45 km/h, but you must stop completely (0 km/h) before hitting the next ATP zone. Failure to do so will trigger the emergency brake. Emergency stop from 45 km/h here would gurantee a complete stop in ideal conditions within zone 0 (see below).

Code 0, Zone 0: MSS is 0 km/h, no MTS. When this happens its big shit; the train is very near ahead! Emergency brakes will be used straightaway and maintain on until stop. This is also where all overspeed triggers of MSS will stop at.

While looking at all the text and diagrams, one would wonder, how does ATC and ATP relate to each other here? I chose to integrate ATP with ATC, coming under the ATC umbrella. Protection codes, the MSS. ATC codes, the MTS. In this way, everything becomes clear.

Just something different, when on CM mode and the ATC codes display a lower speed, the train will not decelerate automatically, but the PTO has to do it manually, before hitting the next zone when emergency brake will be applied if the speed is still at MSS!

This point alone shows its difference from ATC systems used in Japan, where train control means braking, automatically, to the speed targeted.

The W-ATC is in fact a type of Cab-Side ATC (CS-ATC). The W-ATC by design is old and quite obsolete, and the new CS-ATC that is in implementation phrase in Japan has a slight resemblance to the Alstom system of waveguide control, a single phrase stopping pattern without using several levels; speed command is given at a shorter intervals with more delicate control (ie more brake commands).

Is there any YouTube video you could pull out off from Japan that the C151A will roughly sound like?

Maybe like the Tokyo Metro 10000/15000/16000? (I know it's Hitachi, just stating an example).
Examples of the recent trains powered by Mitsubishi motors.

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wvbJzeogwiU

Ultimately, only after we know what motor the C151A is going to use will we know how is it going to sound like.

On a side note, Tokyo Metro 16000 series is apparently made by Kawasaki. But since it just came out from Kawasaki factory just recently, nobody knows what it actually sounds like.

My guess is that it will sound like a C371 (http://www.youtube.com/watch?v=ZXLHBd8BmiM).

My guess is that it will sound like a C371 (http://www.youtube.com/watch?v=ZXLHBd8BmiM).
Interesting find, but nevertheless, it sounds almost the same as the Tokyo Metro 15000 and JR East E233 which I have showed since the C371 is using the Mitsubishi motors too.

Motor:
All: AC, three-phrase cage, 150 kW
Checking out on Wikipedia, the C830 motor output is noted to be of 400 kW each. I don't know whether to laugh or cry, and I wonder since when are we running TGV systems.
This is an example of LTA being kiasu. Same thing goes to the running rails itself. The rails used in the NSEW are all UIC60 for straights / UIC90 for curves. And these rails are mainly used for heavy mining purposes. :p

This is an example of LTA being kiasu. Same thing goes to the running rails itself. The rails used in the NSEW are all UIC60 for straights / UIC90 for curves. And these rails are mainly used for heavy mining purposes. :p

Yeah I believe that they are aware of the forces that the train exerts on the rails as well. 15.0 tonne per axle tolerance (30 per bogie/60 per car) is no joking matter. Besides our trains (especially Choppers with worn-out dampers) tend to bounce so much on the rail, if its some low quality it may have been dragged out from the clamps...

The Alstom one is more-less 150 kW. 400 kW is way over logic for Metro systems.

This is an example of LTA being kiasu. Same thing goes to the running rails itself. The rails used in the NSEW are all UIC60 for straights / UIC90 for curves. And these rails are mainly used for heavy mining purposes. :pThat's most likely a false specification (I am referring to your quote on 400kw motor used on C830). I would generally not trust this source because there's no official data to reference from. And technically speaking, having 400kw motor on our system will cause the system to overload.

http://minibusgrp.com/wp-content/uploads/2010/09/PICT9227_preview.jpg

Of course the wordings are too small, here is a legible (http://minibusgrp.com/wp-content/uploads/2010/09/PICT9227_1920.jpg) version.

Model pose courtesy of Arumi Kanazawa (Yokohama Factory Staff, Tokyu Car Corp --> competitor of KHI :P)

A small article on the LTA/SMRT C151A is on The Straits Time Sept 11th 2010 edition. It talks about the procurement process for the '22 new trains' and include pictures of the propulsion system (no doubt VVVF Inverter), train construction (steel frames), completed carbody (with anti-climbers just like those on the C751B) and 'emergency buttons' which are actually the door situation indicators of the six-car train (taken from a C151).

So far:

Bodywork: Stainless-steel Alumnium-alloy.
Traction controller: VVVF Inverter (IGBT)
Motor: 140 to 190 kW
Drive type: WN Drive
Bogies: Bolsterless
Power configuration: 4M2T/3M3T (non 2-unit EMU)
Regeneration: Full electric brake (to 0 km/h)

These trains will likely come with two signaling systems to suit the upgrading that is done progressively to the NSEWL as well.

Looking at the minimal pictures makes me think that this C151A will very much be alike to the C751B, in fact, one could say its a second batch C751B, not because of looks alone, but on the carbody design and equipment factors.

Even Tokyo Metro Tozai (East-West Line) had a similar history with the series 05. There were those with Electric Chopper and produced from 1988 till 1994 (the last two batches being VVVF Inverter with IGBT), and new trains (dubbed the 05N) in 1999 with improved VVVF Inverter and a new look. The pause of five years was because of upgrading for some of the series 5000 for air-conditioning and negated the need for new trains.

However, looking at the design, one would wonder how much technology has improved over ten years (especially if it does not have a full electric brake!). C751B, and C151A, may well just be a copycat of each other.

thanks for the scan! :)

I really hope they would put at least few seats perpendicular to the side, like in MTR's Metro Cammell stock. Even few at the end of the carriage would do. I hate how you need to counter the acceleration not to fall into someone beside you on the parallel seats.

Signalling upgrade
http://i55.tinypic.com/33uwx3a.gif (http://img.photobucket.com/albums/v637/tamagoo/bus2/TSL/MRT-signalling.gif)

So according to the article, it mentioned that 128 trains will be upgraded in batch to accomodate the new signalling system. It seems that C151A will not have the dual signalling system when it arrives on our shores.

I really hope they would put at least few seats perpendicular to the side, like in MTR's Metro Cammell stock. Even few at the end of the carriage would do. I hate how you need to counter the acceleration not to fall into someone beside you on the parallel seats.

Somehow using a very rough gauge, it would be possible to squeeze three sets of facing seats (2+2+2+2+2+2), a total of 12 seating, for the Siemens in the current configuration if the seats are to face the front and back of the train.

But this would defeat the Metro Law; seats are supposed to be longitudinal to squeeze as much people as possible into the train.

That being said, the original certified load per carriage for the KHI Series 0 (C151) trains at loaded capacity is 320 passengers, 1920 passengers for one train. This is one thing we are quite familiar with, but SMRT recently claiming lower figures, it either has to do with lesser seating (least possible), extra fittings (not logical due to wheelchair spaces) or just to 'please the public'. A definition of 'train loaded' from 1920 to about 1400 is a big difference...

Another article, this time larger (in page dominative size), from The Straits Times regarding the recent train incidents and apparently what the shareholders and users thought about them. They also had one professional from Association of Consulting Engineers Singapore, who apparently compared the heavy rail system to elevators and brushed off the severity.

http://minibusgrp.com/wp-content/uploads/2010/11/ST_SMRT_01112010_A_upload.jpg

http://minibusgrp.com/wp-content/uploads/2010/11/ST_SMRT_01112010_B_upload.jpg

One important wake up call (for the shareholders, unknowing public and professional elevator engineer) from the headline of this article: There is no such thing as more trips = more breakdowns.

The increased number of trips done by the trains could allow a bigger margin for error and breakdowns, but why would the amount of actual breakdowns go up? Following are two possible reasons.

Number one, maintenance had been kept at a normal level (ie. no increase in frequency of train checks) versus the number of trips a train is ran. There are ten trains, any eight of them are always on service, two are rotated every week for checks. Now, due to the increase in service, there is only zero to one slot for checks, but the duration of the check is still rotated at once per week. Any problems on one serving train, there is a wait of zero to six days before it can be rectified, because there is a high service demand but slow maintenance rotation.

Way to solve this is to rotate the trains more frequently, place them in service but rotate every few days to be checked and rectify problems which may affect service. Things like these are air-conditioning (there are cases which one evaporator was taken out and train running on service, 045F car 1045 as an example for this year), lighting and non-vital components. Running components may have to wait for more important checks before they can be corrected, as this takes much more downtime. Dedicated companies however, can negate this by placing a substitute train directly on that day and work on the complicated defect.

Number two, defective trains are being pushed out due to service demand. One that was mentioned was the evaporator taken out for repair. Although the air conditioning is seemingly working, once the rush hour crowd comes onto the train it would become unbearable. Complaints are bound to follow.

A more serious condition would be brakes and power system not being satisfactory but the train is still pushed out for service. Due to the majority 80s digital system (8 and 16-bit) on the C151 trains, there may be faults that are not shown or not accurately detected when diagnostics are run. There may be one worn brake pad that shows okay when checked, due to other three on the same car are working properly and can be engaged to a satisfactory condition. That one worn pad would have failed (quite miserably) when the friction brakes on that car engaged to emergency when the safety system was tripped, possibly at high speed (a scenario). This would have caused quite some smoke (especially on a rainy day) and cause unknowing (and not knowing) passengers to run in all directions (while in actual fact they should be thankful the train had 23 other brake pads that, Amen, worked well).

Such are some of the possiblities I have explored during the past week in (Army) camp, reading this article over and over again, consulted the MRTC C151 specifications (that I have brought in as well, to occupy my scheduled academic time) and technical studies, written by professionals with over half a century of dedication, from the Land of the Rising Sun.

Numbers are always amazing. 1100 trips since February 2008. 1.5 incidents per one million kilometers travelled. Now, not.

Two years (up till February 2010, benefit for the doubt), 24 months, (a very) average of 29.5 days per month, total of 708 days. 1100/708, 1.554 trips increased per day. How amazing is this? Taking one train with one evaporator removed and putting it on service? Or that fated fellow with a worn brake pad. A wad of complaints, a boom and frightened passengers, service delay and another wad of complaints, that is how amazing it would be. Just for those 1.554 trips per day.

1.5 incident per one million kilometers travelled. Just take the main lines, North-South is 44 kilometers long, it has 25 stations. Taking that there are (stations x 1.6) number of trains, which mean 40 trains. Each train does about 13 directional (6 1/2 round) trips per day. 44 x (25 x 1.6) x 13 = 22880 kilometers. Using the same formula, East-West travels 31724.16 kilometers per day (possibly more due to higher TPH, train per hour, on this line). A total of 54604.16 kilometers per day. A million, divided by this, is 18.31 days. That is for 1.5 incidents. 12.21 days is the threshold.

On any 12.22 days, an incident could occur anywhere on the main lines, from a 'boomz' brake pad, to a passenger caught in the doors, to someone falling down the escalator (does escalator mileage contribute to this? It would be taxing to calculate how much mileage an escalator does everyday!), to someone falling onto the tracks (not sure if this contributes too, to 'incidents'), to a TO who overrun and underrun so badly that he gets swapped out at the next crew point (case by case?), to a overrun, just one, that requires the train to head to the next stop just because the circuit cannot be overridden, and just about 1001 other reasons you can think of that will happen in this 12.22 days, that will go unreported.

Numbers are numbers, hopefully, for the fooling of the general public. When bits and bits count into operations, numbers no longer fool, they show how weak the system is and how much leeway there can be for mistakes to occur.

I shall not go on about how to improve the rules and regs, as I am not a law student and I do not write this to improve the law. Technical yes, anything is welcomed, even a job (think and dream on!) in MRTC.

The tagline of More train trips, so more breakdowns, in my humble but realistic, true-to-the-fact and dedicated engineer's mind, is nothing but plain bullshit.

^^ well said. as the rolling stocks make more trips daily carrying heavier loads, and as the trains start ageing beyond their intended lifespan (C151 anybody?), the maintenance schedule should be refreshed so essential checks can be done more frequently despite increased services.

The C151s are aging quickly, yes, but the average lifespan of a rapid transit train is about 40 years. The C151s have only experienced half of that. They are no where near retirement.

Besides, if they were gonna get rid of them now, why would they bother spending millions of dollars on a refurbishment program right before their retirement? That wouldn't be too prudent, would it?

The C151s are aging quickly, yes, but the average lifespan of a rapid transit train is about 40 years. The C151s have only experienced half of that. They are no where near retirement.
That's not true, if the train is being operated at extremely high cycles, it can affect its lifespan.

The C151s are aging quickly, yes, but the average lifespan of a rapid transit train is about 40 years. The C151s have only experienced half of that. They are no where near retirement.

Besides, if they were gonna get rid of them now, why would they bother spending millions of dollars on a refurbishment program right before their retirement? That wouldn't be too prudent, would it?

Our trains are actually straddling the line of 'well worked' (which means bang for the buck) and 'over worked' (which means revenue < maintenance fee).

One major damage to train components is salt. In fact, any metallic elements. Corrosion can cause early retirement of trains, reducing its lifespan by 15 to 20 years, if not well coated and designed. Our trains don't run next to the sea, but quite near it. Parts get damaged over time and replacement is necessary, till the day when the body started to show corrosion, that is when the lifespan is up. Acid rain plays a part in this too.

C151 is specified for 30 years (MRTC). Much of the components made satisfies and often exceeds this limit, including fireproving for 45 minutes and structural limits.

The improvement works done to the C151, I would consider it as a asthetics upgrade more than a lifespan extension. Nothing done to the trains have extended its actual running lifespan. Note that all the modifications done are to improve your ride experience, limited only to the passenger cabin! Nothing is done to the machinery below the train. SMRT explanation is that the machinery has performed 'better than expected' (Wiki). I would attribute this to lack of expertise in SMRT for modification of running parts and reduction of overall cost.

Performance of the C151 is much based on energy saving (trying to give back as much as what was taken) than actual running performance (MRTC). This is one important milestone that paved the way for the now SMRT to win awards, apparently against European and American counterparts, in terms of energy saving. C151 also set numerous standards in rolling stock for MRTC that is used to date, in order to maintain the energy saving factor. Little is considered for performance in terms of power on par with the update of technology.

* Some brackets denote sources.

Oh, I'm well aware that nothing was replaced except for interior fittings. I'm not saying that the refurbishment extended the lifespan of the C151s. That could only be possible if the motors and such were all replaced.

Oh, I'm well aware that nothing was replaced except for interior fittings. I'm not saying that the refurbishment extended the lifespan of the C151s. That could only be possible if the motors and such were all replaced.

Yup I got your understanding. The statement was to enlighten those who are not aware of that point.

Taken from the Japan thread in "Subways and Urban Transport" - a model of the C151A.

Next up are the Singapore MRT C151As:

http://img576.imageshack.us/img576/8475/dsc4228.jpg

http://img191.imageshack.us/img191/262/dsc4230a.jpg

http://img9.imageshack.us/img9/3402/dsc4232.jpg

http://img545.imageshack.us/img545/6203/dsc4234e.jpg

Looks pretty similar to the C751Bs except for a few minor modifications. Personally, I like them, and the entire train as a whole. I only assume this is the finalized design.

As for why the car numbers are X5XX, I have no idea. I was assuming that they would start at X401, since it would follow up from where the C751Bs' set numbers left off.

^^ out PTOs are a tad superstitious these days. ask SBS Transit how many 4s they have among the thousands of buses they have newly registered recently? :lol:

the train looks a lot like the C751B. but hey even the C151's exterior is stickered to resemble C751B. no interior shots of C151A by any chance? I think that is where the bulk of difference (if any) lies.

Thanks for the re-post, that is some useful data on the C151A. Here is a (very direct) translation of what is on the specifications poster seen here:

http://img576.imageshack.us/img576/8475/dsc4228.jpg

C151A Electric Metro Trains for Singapore LTA
"C151A" is the electric metro train for Singapore LTA (Land Transport Authority).

These new trains are introduced to the local lines (lol) in Singapore (NSEWL) with the aim of improving peak hour loading and energy efficiency. The "C151A" is also designed to the specification of increased capacity yet controlled energy consumption, and is expected to improve the capacity of the local lines.

Formation: 6-car (DT-M1-M2-M2-M1-DT)
Seating: DT: 50, M1: 50, M2: 48
Length: 23830 mm
Width:3200 mm
Height: 3690 mm
Gauge: 1435 mm
Highest operating speed: 80 km/h
Body: Aluminium
Acceleration: 3.6 km/h/s (1.0 m/s)
Deceleration: Service -4.32 km/h/s (1.2 m/s), Emergency -4.68 km/h/s (1.3 m/s)
Supply: 750 VDC third rail
Bogie: Axlebox-supported axle type (monolink), bolsterless air spring bogie.

Acceleration figures have not gone to a suprising level; it should not, as the oldest stock can only achieve 3.6 and these trains are designed to supplement, not replace or improve the system by a lot. However, I think that SMRT should look towards figures such as 4.0 km/h/s as it is easily achievable with a 2 to 1 MT ratio. Through a high acceleration can true system improvement come about.

Deceleration figures however show a good sign, with maximum service braking (counting in CM operations, not ATO braking) up from -3.6 km/h/s (in the Chopper C151 trains) to -4.32 km/h/s. High deceleration not only means better safety aspect, but also accomodates tighter train distances as trains can 'compact' with deceleration well within safety range (takes lesser time and distance to stop completely).

There is however no improvement in the emergency braking values, probably due to SMRT conforming it to other stocks which only has -4.68 km/h/s for their EMG braking. This reduction in gap for maximum service and EMG brake may only remain as an ambiguious matter (no right no wrong).

Taking the Tokyo Metro Tozai Line load factors and definitions, which has figures of loading very alike to our own Tozai, or East West Line, here are the projected load factor for the C151A. Load factor is based on JIS (Japan Industrial Standards) E 7103.

Empty = 0%: 0 passengers (duh!)
Fully seated = 35%: 296 passengers
100% load factor = 100%: 845 passengers
Load factor aim for Tokyo Metropolis area = 180%: 1521 passengers
Tokyo Metro Tozai Line mean load factor = 199%: 1681 passengers
LTA specified 100% load = 1920 passengers: 227% load factor

In simple terms, load factor does not mean exact loading, percentage overload or complaint shitstorm percentage. It simply gives operators a gauge on how much space a passenger is having, which is somewhat proportional to how the passenger would feel when he/she is in the car. JIS E 7103 defines each passenger to have 0.3 meters square of space, in other words, 1 meter square accomodates about 10 passengers.

227% to the Japan side is considered overcrowding, as they are pushing to reduce load factors below 180% (for Tokyo) currently, not only on Metro lines but also private railways with mixed service (local to limited express).

Another definition of load factor can be seen via computer statistics that SMRT compiles every month. They may not be adopting this rule, but this is how it works in Japan.

Load factor = Passenger carried / Passenger capacity x100%
Where also,
Passenger carried = Passenger passing through the system
Passenger capacity = Capacity of trains x number of trains run

Feel free to ask questions, I will answer to the best of ability.

I like the exterior design. Now, looking forward to seeing the interior.

Again, another missed opportunity at utilising plug doors.

The exterior looks like a slightly more rounded-off version of the C751B; the black portion at the front is rounded rather than being squarish, and the headlights area is now one ovoid rather than two separate circles. Otherwise, I see no differences...

^^ out PTOs are a tad superstitious these days. ask SBS Transit how many 4s they have among the thousands of buses they have newly registered recently? :lol:

the train looks a lot like the C751B. but hey even the C151's exterior is stickered to resemble C751B. no interior shots of C151A by any chance? I think that is where the bulk of difference (if any) lies.

This superstitious avoidance of the digit 4 and the love of digit 8 has got to stop. After all, everyone will die someday, and materialism doesn't equal a better life or society.

The more they avoid the digit 4, the more I will love it. The more they love the digit 8, the more I will avoid it like the plague.

Edit: original post time at 9:04PM :D .

The little differences in the 151A and the 751B have often suggested myself to name this the Series 300N, meaning just a newer version of the Series 300 which is the 751B.

The length of the DT car has increased from 23650 mm of the Choppers to 23850 mm of this 151A. That means about 200 mm (20 cm) increase in the front curve... Again, similar to the 751B.

In order to fit into existing PSD and station structure, the length of the DT can only be extended to the front. It could be made as long as a nose of a Shinkansen train, but M1 and M2 cars would remain the same (22800 mm).

The little differences in the 151A and the 751B have often suggested myself to name this the Series 300N, meaning just a newer version of the Series 300 which is the 751B.

The length of the DT car has increased from 23650 mm of the Choppers to 23850 mm of this 151A. That means about 200 mm (20 cm) increase in the front curve... Again, similar to the 751B.

In order to fit into existing PSD and station structure, the length of the DT can only be extended to the front. It could be made as long as a nose of a Shinkansen train, but M1 and M2 cars would remain the same (22800 mm).

But unless it's tapered to a point, won't there be a risk of the nose scraping the tunnel walls/platform edges when it's rounding a bend, if it's hypothetically that long?

C751B's didn't scrap the tunnel walls and platform edges, so they probably have done some conversions prior to the introduction of C751B's.

Now that the first set of C151A has landed in Singapore...

Any chance to board it while it does a test run? :D Remember boarding C751B for a special AMK-MRB-AMK run on a weekday afternoon years back...

Haha not sure but instead of a test, I would love a tour of the entire 'underside' of the train XD

Passed by Bishan Depot on a 751 today, saw the guy in Lane 17 lit up, perhaps undergoing static tests.

I really hope they would put at least few seats perpendicular to the side, like in MTR's Metro Cammell stock. Even few at the end of the carriage would do. I hate how you need to counter the acceleration not to fall into someone beside you on the parallel seats.

Hmm....perpendicular seats? Like what they use in Taipei?

http://images.travelpod.com/users/4urtravelnmore/taiwan_2007.1179278400.img_1046.jpg

Anyways, amazing thread filled with intellectual and technical discussions. I've definitely learned a lot from these discussions so thanks, TIB1224Y :)

^^ Yeah. Since they take more space I was hoping for them just at the ends of each car, as I find them more comfortable than the 'longitudinal arrangement. Oh well, we all know its not gonna happen anyways so its quite pointless to suggest it from my side.

^^ I agree. I am sure LTA would say that they have done all the research and have concluded that the present configuration is the most suitable one for our MRT system. Maybe, in the future but not likely in the near future.

I'm almost certain that Taipei's cars are wider. However, this arrangement would waste no space... only because standing passengers during rush hour don't even fill up all the available space anyway.

On the first page posted last year, I had some 'expectations' of the C151A based on advancement of train technology since the last rolling stock ie. the C751B made by Kawasaki and Nippon Sharyo (川崎重工/日本車輌) and propulsion/electric system (VVVF Inverter, Motors, Static Inverter (SIV), controllers and full electric system) by Fuji Electric Systems (富士電機システムズ).

The expectations are now compared with the specifications that can be confirmed so far.

Expected:
Bodywork: Stainless-steel
Traction controller: VVVF Inverter (IGBT)
Motor: 140 to 190 kW
Drive type: WN Drive
Bogies: Bolsterless
Power configuration: 4M2T/3M3T (non 2-unit EMU)
Regeneration: Full electric brake (to 0 km/h)

Actual:
Bodywork: Aluminium --> Confirmed
Traction controller: VVVF Inverter (IGBT) --> Unconfirmed
Motor: 140 kW --> Unconfirmed
Drive trype: WN Drive --> Unconfirmed
Bogies: Monolink Axlebox, Bolsterless --> Confirmed
Power configuration: 4M2T --> Confirmed
Regeneration: Unconfirmed

Once again, the 'expected' specifications is based on the train technology advancement over this 10 years, including ways to minimize energy spending (top priority of MRTC/SMRT Corp) and increase ride comfort. Sadly from what can be seen above, and once again it proves that MRTC rules laid down almost 27 years ago (C151 was made in 1984) has not moved much, and cannot be expected to move much as well!

One of the many things which I have been interested in knowing other than the components underside the C151A is the layout of the handgrips and poles.

The arrangement of the poles and handgrips in most trains currently does not encourage passengers to move towards the centre of the car, which is especially true in the case for C751B and unmodified C651 where passengers has nothing to hold on to if they are not near the poles/handgrips/doors/leaning support.


My ideal arrangement would be;

- No poles at all in the carriage other than the partitions at the ends of the seats and those by the side of the doors and gangways.

- Handgrips spanning throughout the whole train, including spanning the handgrips over the areas doors. Also, to ensure that the standing space is being used optimally, place handgrips perpendicular to the travelling direction across the train instead of only placing it parallel to the travelling direction.


But due to the way the local trains are configured, making such changes would obstruct the covers of certain components within the roof when maintenance is required. Thus the way the supports are placed will have to be changed/modified when the handgrips layout changes.

The order trains with the most ideal layout to the least in my humble opinion;

1. Bombardier Innovia APM 100
2. Kawasaki C151 (Refurbished)
3. Siemens C651 (Modified)
4. Mitsubishi Crystal Mover
5. Kawasaki/Nippon Sharyo/Tokyu Car Corp C751B
6. Siemens C651 (Unmodified)

For those who have taken Bombardier Innovia APM 100, you would have realized that the handgrips found on the trains are all over the place. This train has the most ideal handgrips layout, which includes having the handgrips spanning over the door area when compared to other trains in Singapore. It is only pulled down by the presence of poles in the middle of the train and the lack of handgrips that spans perpendicular to the direction of travel.

The unmodified Siemens on the other hand, has the most minimal amount of handgrips for passengers to hold onto, which encourage the passengers to crowd around the walls, poles and doors for support instead in areas without handgrips.

Though the C151, C751B and the Mitsubishi Crystal Mover in Singapore does not have the most ideal handgrips layout, most of their Japan counterparts on the other hand has all the ideal points I have specified above such as this, one of the C151's big brother back in Japan;

http://img521.imageshack.us/img521/8936/55635013.jpg (http://img521.imageshack.us/i/55635013.jpg/)

For those with sharp eyes, the C151 (Refurbished) has an air-conditioner layout that is similar to the the train above.

So now, what kind of handgrips layout will the C151A adopt?

Looking at past records, it's either a layout that is similar to the refurbished C151 or the C751B.

Of course, a change to the layout (for the better, not worst) is always welcome too and I would be happy if the layout is similar to the C151's big brothers back in Japan.

My ideal layout would to be to have a mixed layout with the most hanging straps possible. They could adopt the C751B-style center overhead bar (with a ton more hand grips, of course) and put slightly lower overhead bars directly over the seats for passengers to hold on to. I think that's the only way people will ever fill up all of the available spaces.

All of Taipei's fleet is currently being modified to include this design of overhead bar in the area near the doorways:

http://www.dorts.gov.tw/site/tcg/public/MMO/dortsc_media/08tech/MG_1060475.jpg

The circularly-shaped bar allows passengers to hold on. This would encourage the use of this space, although there isn't much of a need for that...

Smelt attempt to discuss about increasing 'grabbing' capacity of trains, let some MRTC specifications guide it along! I am very interested to learn and see who can provide the best configuration suggestion, for myself is not well versed in that field.

'The maximum vertical loading for structural design is 21660 kg (380 passengers) although the maximum envisaged service loading is estimated as 18240 kg (320 passengers).' (MRTC Proceedings pg 412)

^^ I guess it is saying the maximum stress that it can hold is so much and yet for the certain amount of service time, they have a safety factor of a certain percent to ensure a longer time of usage. :)

As I was doing my routine search around the web, an interesting find lead to the sealing of fate of my quest of finding the 'gold' of the C151A (and letting me rest my mind for perhaps 10%? for the rest of the 7 weeks ahead).

http://minibusgrp.com/wp-content/uploads/2011/01/N5030-800px.jpg
Screenshot for your reference.

Translate:
Fuji Electric Systems completed the development of the propulsion system and auxillary power system (Static Inverter, SIV) for the 22 sets/132 cars C151A for Singapore MRT. These systems are handed over to Kawasaki Heavy Industries, and when (train) tests are completed, will be used on the (extra) trains for NSEWL.

The systems are developed based on those already in use on the C751B, and this achieved reliability and short development time. The high standards in safety on software is checked based on the SIL2 of IEC 61508 safety standards, pushing safety beyond the levels of the current standards (this last part is really lame but its how it is written).

So for people hoping that its a revolutionary new PMSM (permanent magnet synchronous motor), fearing that it is a China made ready-to-boomz motor, or like me, simply wondering which Japan consortium will provide the systems?

Your quest ends here.

Fuji Electric Systems has conquered two (out of four) of the IGBT semiconductor, VVVF Inverter type rolling stock in Singapore.

Extra talk...



Looking at the minimal pictures makes me think that this C151A will very much be alike to the C751B, in fact, one could say its a second batch C751B, not because of looks alone, but on the carbody design and equipment factors.

Even Tokyo Metro Tozai (East-West Line) had a similar history with the series 05. There were those with Electric Chopper and produced from 1988 till 1994 (the last two batches being VVVF Inverter with IGBT), and new trains (dubbed the 05N) in 1999 with improved VVVF Inverter and a new look. The pause of five years was because of upgrading for some of the series 5000 for air-conditioning and negated the need for new trains.

However, looking at the design, one would wonder how much technology has improved over ten years (especially if it does not have a full electric brake!). C751B, and C151A, may well just be a copycat of each other.

Reviewing a post last year on 11th September 2010, looks like my predictions have indeed came true... Design, propulsion, even down to electrical systems, is nothing much of an improvement from 10 years ago. That is, based on paper alone. The final verdict will come when we step onto the train and verify for all eyes and ears.

Well... I was hoping they could use permanent magnet synchronous motors, since those motors, I heard, are able to save energy and electricity.

Oh well, there's still the new trains for the North-East Line and the Circle Line...

p.s. PLUG DOORS PLEASE.

Edit: oh yes, the other day when I was passing by Bishan Depot on the train, I saw a C151A train sitting inside the depot with the lights on. I think they might be doing some preliminary tests on it. I guess the next step is to test it running on the test track inside Bishan Depot, before taking it out for a test run on the main lines itself?

Yes, the train is currently undergoing static testing. Once the train has passed the static test, it will move on to dynamic testing on the test track and main lines.

Ok, pictures are up on MoT's Facebook and Flickr. The interior seems generic and there's nothing remotely new about it. There you go:

http://www.flickr.com/photos/motsg/sets/72157625895160610/

^^ Thanks for the updates. With regards to the handrails, it is interesting to see that there are 3 rows of handrails. That's a lot of handrails!! :lol:

Ok, pictures are up on MoT's Facebook and Flickr. The interior seems generic and there's nothing remotely new about it. There you go:

http://www.flickr.com/photos/motsg/sets/72157625895160610/
The fact that the purchase has to go through LTA is really a salute to SMRT's 'design'.

I'd have expected the trains to have something similar to the Bombardier's interiors.

^^ Thanks for the updates. With regards to the handrails, it is interesting to see that there are 3 rows of handrails. That's a lot of handrails!! :lol:
You say "a lot", I say "just enough". :P There are still waaaaaay too few hanging straps.

^^ Thanks for the updates. With regards to the handrails, it is interesting to see that there are 3 rows of handrails. That's a lot of handrails!! :lol:
I'll add in my thanks too. :) Finally! That's what I've always thought would have been better. Along with our double rows on the refurbed 1st gen trains, add another row in the middle. It would encourage people to stand there then. Good to see that they are doing it now.

delete

The fact that the purchase has to go through LTA is really a salute to SMRT's 'design'.

I'd have expected the trains to have something similar to the Bombardier's interiors.
Aren't the refurbs Rotem designs?

I can see that the interior design is based more on the refurbished C151 than the C751B. In fact, it seems to mix elements from the original C151, refurbished C151, and C751B (especially the thematic design from the last one).

http://minibusgrp.com/wp-content/uploads/2011/02/5030-800px.jpg

Going over old records of Fuji Electric, the news on the supply of propulsion system for C751B was seen in the Year 2000 annual progress report. This shows the benefits of housekeeping; your next generation can dig out and expose the details!

Translate:
The Metro (MRT) is the staple transport method for the people of Singapore, as the country limits vehicle entries into the Central Business District. The Land Transport Authority (LTA) plans to increase its fleet for the MRT Changi Line extension. 126 cars were ordered from Kawasaki Heavy Industries and Nippon Sharyo, of which Fuji Electric is to provide the main circuit equipment (propulsion inverters) and Auxilary Inverter (SIV). Late 1999, the first train set was tested without problems. All 126 cars will be placed into service by April 2001. The following is the description of the electric systems.

VVVF Inverter: IGBT controlled 'One-time Flux Standard' Stator Flux Vector Control (Field Oriented Control, FOC), highest output 415 kVA x2, 84 units (one per motor car).

SIV: IGBT controlled inverter, with battery charger, 80 (constant 55) kVA + 16 kW (battery), 126 units (one per car, including trailer cars).

This article literally blew me away for the past two hours. Stator Flux Vector Control? I thought I was looking at Propulsion to Mars. However, looking at other articles, it didn't seem so hard.

Simply to put, its a 1C2M 2-level IGBT-controlled VVVF Inverter. One set of controller controls two motors, and the IGBT semiconductors are placed in two-per-level configuration. 2-level IGBT controllers are suitable for lower voltage range operations, while 3-level controllers are used on high voltage inverters eg Shinkansen trains.

Hence the C751B is 'bogie controlled', one controller (akin to one accelerator) controlling two motors on the same bogie. They will synchronise with each other based on speed, and feedback these information to the main computer, which will adjust torque to give the highest adhesive effort.

^^ Thanks for the detail analysis as usual. It is interesting to know the technology being used for the MRT lines. :)

Train in BSD Track 17 is not present. Should be preparing/undergoing dynamic tests.

I wonder why no one has posted about this, but C151A train set x501/x502 is now undergoing test runs on the main lines.

Videos (not by me):
http://www.youtube.com/watch?v=DgBDUrcBXZY
http://www.youtube.com/watch?v=fzSKWjy8aQA

x507/508 spotted on test runs nw at Yishun NB

501F is doing test quite often on the Airport Line now, during weekdays 12 to 3 pm non-scheduled. Run number is 741. Catch it if you have the time.. Two other trains, 503F and 505F are also said to be in Changi Depot.

I saw one in Ulu Pandan depot yesterday and today morning.

^^
That should be 507 and 508.
My guess is that 501 and 502 is also kept in Changi Depot as it's running along the Airport branch line these few days.
509 and 510 and other new sets should be at Bishan.

Based from today's deployment, 501F thru 505F were parked at Changi Depot, 507F at Ulu Pandan and 509F at Bishan Depot. 505F was used on Changi Airport Branch Line but withdrawn before noon. 507F was used on North-South Line but withdrawn during its first trip at Ang Mo Kio, after which 509F took over its shift (150M) and continued until another change of shift occurred to make it 115M. It was temporarily withdrawn at Jurong East EWL platform B/C at 1700h and headed east presumably to Ulu Pandan Depot as 315M. Reported to resume service on North-South later.

Changes to the train vs their schedule, morning 0600-hour compared with 1600-hour.

115M, 071F >> 509F (withdrawn at JUR)
116M, 347F >> 071F (as 115M in the morning)
148M, 001F >> 123F (as another run in the morning)
150M, 507F >> 335F (as 114M in the morning)

Impressions as a Passenger/Rolling Stock Specialist

Of course, that title up there is not official. But to recognise what I do, that is one fitting title, I feel, that I would give myself.

The first trip on 507F running 150M from Ulu Pandan Depot was largely normal. Good saloon lightings feel that the train is very warm ('visual' temperature) to enter, strong air conditioning flow eliminates the warm feeling. A fair amount of handgrips for the standing passenger, however sparsely spaced out at the center row, near the doors. Another failure attempt to woo people into moving in. Poles are a bit too thick on width and may be hard for young kids to hold onto. Grab onto your mama instead.

Sound-proofing near doors is below-average; normal vehicular sounds at the road near the train could be heard with all doors closed and running sounds emitted by equipment can also be heard clearly. Panels and fittings used in the saloon resembles those used on local China products; the design and touch of Japanese quality is no longer visible, although the name of Kawasaki is still carried on the trains' builder plate together with CSR Qingdao Sifang.

Seats (tried on 509F) were up to good width, about 50 cm per 'butt space'. Good height means cramming of legs due to prolong seating is largely eliminated. Nothing more to compliment these plastic constructions.

Performance of air conditioning, like mentioned before, is largely positive. No loud noise from blowers, and adequate ventilation in the saloon.

Running performance of electrical control components (propulsion system) is largely positive as well. Quieter torque-CVVF transition sound from the motors no longer associate this train as close as to the C751B, however the iconic 2-Level IGBT sound remains. Motors are tuned to maintain the strong power they had like the C751B. A possibly enhanced system also meant the ability to do speed control when braking down a slope (observed between Choa Chu Kang to Bukit Gombak).

The stronger service braking (enhanced from 3.6 km/h/s to 4.3 km/h/s) meant better braking performance but worsened passenger comfort; it was used on 509F when it entered EWL platform at Jurong East for its short withdrawal. Full Service Brake (FSB, electric plus pneumatic) was applied around 20 km/h and passengers had danger of falling, first when electric braking was cut off at about 5 km/h (the transition to strong air braking) and then quickly again when it hit 0 km/h.

Bogies have not undergo 'seasoning', damping effects while engaging R=350 to 400 curves is akin to a well-seasoned C751B. I wonder if the performance is still to deteriorate over some time.

Above are only personal comments, not representative of any companies or individuals. They are based on experience in analyzing rolling stock performance and design, mainly from Japan, addition with those European and the World.

Are there any videos of rides on the C151A trains yet?

Jurong East Platform A to Bukit Batok on set 509/510
http://www.youtube.com/watch?v=G3SchJJlr4g

Expo to Tanah Merah on set 503/504
http://www.youtube.com/watch?v=rCGlAGEhxOY

There will be more videos to come, just look out for it. :)

Sucks that they have so many problems apparently. More testing (and maybe not letting China assemble them) could have had fixed the problems.

Still, this is their first day in operation. Forgiven.

504 is doing a eastbound run now. At Tiong Bahru. Announcement system is slightly faulty.

were there as many teething problems when C751B started rolling? its either the lack of time for rectification and testing or just poor quality. wonder what are the views on this?

Hopefully there won't be too much problem with the remaining 17 trains when they start operations in December. Set 513/514 is already running tests on the main line, there should be ample time (6 months) compared to the 5 new trains which were only given 2-3months of testings.

It was mentioned on the papers that testing for subsequent trains will take a shorter time. This is true technically as problems found on earlier tests can be used to improve before new trains are sent for their own testing, and hence further problems reduced.

New units may be introduced progressively over a few months until all 22 units are in service December 2011.

I remember that the 3G trains had to be taken off service around 2002 as they had faulty gear boxes. Out of the fleet of 21 trains, 20 were grounded. Metal bits were detected in there.

To be honest, I think everyone is really being a perfectionist. There's not much wrong with the 4G trains and minor faults are to be expected with the first batch in service. For 504, once the driver reset the announcement system, it was working pretty well. Only the STARIS was acting a little crazy on a few light-up maps. Have you ever seen random stations just light up? A few of the following were lighted green all at once - Jurong East, Clementi, Outram Park, Tanjong Pagar, Bugis, Lavender, Tampines, Changi Airport and a few on the NSL as well.

For those who have taken one of the new 4G trains, do you feel that the handle bars/grab poles are huge? They are definitely larger than previous generations of trains.

Hi mrtfreak, I guess you may have gotten the term '4G train' or '3G train' from the batches of trains that MRTC/SMRT bought. However on an overall perspective, it would be sharing the title of a 4th Generation train with a 1994 product. Why so? Lets take a tour back on the generation of EMU trains developed over the World.

1st Generation: Resistive Cam Control without regenerative braking (however can incorporate electric braking), DC motors. From start of EMU development in the 1930s, has since stopped (outdated). Very limited production.

2nd Generation: Resistive Cam Chopper Control with or without regenerative braking, DC motors. Developed since 1950s, has since stopped (outdated). Still in limited production.

3rd Generation: Thyristor Chopper Control with or without regenerative braking, includes 4Q-GTO Electric Chopper, DC motors. Developed late 1960s up to late 80s, development has since stopped (outdated). Still in limited production.

4th Generation: VVVF Inverter Control with regenerative braking as basic, includes GTO and IGBT semiconductors as a controller medium, AC induction motors. Developed since 1980s and re-engineered, in-production now.

4.5th Generation:
VVVF Inverter Control with Permanent Magnet Synchronous Motors (PMSM).
VVVF Inverter Control with linear induction motor propulsion (eg. Toei Oeido Line).

5th Generation: Future technologies (Post-VVVF Inverter)

The C151 with the 4Q-GTO Electric Chopper belongs to the 3rd Generation of overall EMU technology, the C651, C751B and C151A all belong to the 4th Generation.

4th Generation of EMU development would be the trains that we had with and after the Siemens that came in 1994. Technology has by all right, not advanced after that on our rolling stocks. Internal equipment, down to the STARIS.. were only cosmetic differences. To an engineer, nothing has advanced except for further R&D of possibly certain running equipment and materials used.

I would agree that the C151A is a 4G train in terms of batch only to local Singaporeans who do not have an inkling on trains, however it would be only correct to name it this way in terms of batch, although internationally it does result to be a 4th Generation (bearing with mind it shares the 4G title with a 1994 product). We have stopped at VVVF Inverter technology, only advanced in terms of actual drive units and methods, for the past 30 years (from the early 80s). Similar to Chopper technology, it looks like we will stop here for a long period before the next breakthrough comes about.

Note: Electric braking means using the motion of wheels/motor to create an electric field of resistance to slow the train down, by no means this electric can be returned to the electric grid and all are burnt off as heat. Regenerative braking means the motor is turned into a generator, field created to slow the train down and generate electric to be fed back into the electric grid. Regenerative braking does not work for old railway lines as this energy cannot be effectively received by substations which does not have inverters/large capacitors.

Yup, referring to it locally. Can't be bothered to find the definite C-whatever-evers. Just find it easier to call it Gen 1, 2, 3 or 4 based on the order for the local system. In this case, the thread refers to the local transit system so it should be understood within that context. :)

Yup, referring to it locally. Can't be bothered to find the definite C-whatever-evers. Just find it easier to call it Gen 1, 2, 3 or 4 based on the order for the local system. In this case, the thread refers to the local transit system so it should be understood within that context. :)

By technological development however these trains are still considered to be 'henta-kaki' (marking time) on the spot.. So by saying 4G = 4th batch yes, by local technology its only a 2/3G? product..

I share your views on the width of the handgrips among other stuff, you can check my post ^^ to see what I observed too..

^^ since C151As are ordered and developed on short notice (about 2 years) to fight fire, I can understand why they are near carbon copies of C751B motors and refurbished C151 aesthetics. but are the 4.5Gs out in late 90s when the C751Bs are being developed? it enjoys a longer developmental timeline and might have been excluded then due to cost.

the next 13 trains are due 2016 when Tuas West Extension begins operations. if they start now they might be able to take advantage of newer systems, though they are unlikely to update specifications set back in the 1980s.

I really wish they do. In fact, I think they must if they want to improve the situation on the original MRT lines.

A few things I'm asking for in the 13 new trains:

- slightly wider bodies, thinner walls, and plug doors (to accommodate more commuters)
- wider windows (think North-East Line's C751A trains)
- improved acceleration and deceleration
- shifting of grab poles from middle of car to the sides, near the seats
- maybe overhead luggage racks? These might come in useful should they be deployed on the Airport Branch Line, or if SMRT brings the Airport through-train back
- LCD screens (a.k.a. SMRT's STARIS 2) as standard
- noise-reducing skirts on the sides (I know our MRT viaducts already has some noise barriers built-in, but having skirts on them might help silence them further. Also, remember the ground-level section near Ang Mo Kio - it's in a residential area and yet has no sound barriers of any kind)
- cars with foldable seats that can be lock-closed during peak hours (similar to what Japan has)

train bodies are unlikely to be much wider since tunnels are optimized for current sizes of trains. I dont think there is much space left to cut, the frames of our trains are already quite thin. acceleration and deceleration may be updated, but cant take effect fully until all our stocks run on the updated specs to prevent bunching.

other suggestions seem pretty viable if the relevant authorities are willing to pony the cash for it such as foldable seats, noise reduction technologies and LCD information screens. if they are going to have bar trains again, I will recommend they replace the bars with those used on Taipei metro. it is also all stainless steel, but a lot more comfortable for sitting down.

Our train bodies are already wide type for the gauge.. 1435 mm, the optimum body width is 2700 mm (express design) to 3000 mm (flat sided Metro), ours is a generous 3200 mm.

Height wise its also low, at 3690 mm, most trains with 2800 mm width go for height of 4000 mm. Overall our train CG is lower than commuter trains.

However this low ride height limited the design of bogies and underfloor equipment has to be compressed into that little space, hence our train bodies are long to accommodate all those stuff.

Acceleration and deceleration is also optimum for a Metro system, unless you opt to have a good upgrade of all the stocks, if not it would be hard to run a Metro (all-stop) system with stocks varying too much in performance.

Singapore is 3.6 km/h/s from 0 to 35 km/h generally.

New York subway has acceleration figures of 4.0 km/h/s (R160), one of the more impressive ones I have seen. Japan ones stand at 3.3 to 3.5 km/h/s generally, highest 4.0 as well. For multi-tier system, generally with express tracks the local trains can remain at low performance values, however with single direction tracks the trains have to 'dash' from stations to stations to avoid holding up the express trains behind and hence some railways have high performance cars of 4.5 km/h/s (up to 8 in specification) for their all-stop trains.

Europe is agreed to have the highest, with ranges from 2.0 to above 5.0 km/h/s accelerations, but discomfort created to passengers is equally high..

I really wish they do. In fact, I think they must if they want to improve the situation on the original MRT lines.

A few things I'm asking for in the 13 new trains:

- slightly wider bodies, thinner walls, and plug doors (to accommodate more commuters)
I think it has been addressed already. I'm all for plug doors however, it means the platform gap has to be a little teeny-weeny wider.

- wider windows (think North-East Line's C751A trains)
I'm not sure this is wise considering that NSL/EWL trains have a better portion of their route elevated, which may lead to stronger air-conditioning to maintain the 24 deg C temperature.

- improved acceleration and deceleration
- shifting of grab poles from middle of car to the sides, near the seats
- maybe overhead luggage racks? These might come in useful should they be deployed on the Airport Branch Line, or if SMRT brings the Airport through-train back
One thing about our rolling stock is that the walls taper inwards unlike some of Japan's stock which are more or less cuboids, so this may be a problem. It's probably more feasible on the Bombardier Movias on the DTL. Plus someone noted that our trains height isn't high enough. In addition, one comment that SMRT brought up was that passengers tended to hold on to their bags rather than leaving it on the racks.

- LCD screens (a.k.a. SMRT's STARIS 2) as standard
I agree.

- noise-reducing skirts on the sides (I know our MRT viaducts already has some noise barriers built-in, but having skirts on them might help silence them further. Also, remember the ground-level section near Ang Mo Kio - it's in a residential area and yet has no sound barriers of any kind)
Unless you have noise-barriers which cover overhead too, it is useless because sound travels upwards.

- cars with foldable seats that can be lock-closed during peak hours (similar to what Japan has)
Isn't Japan removing the foldable seats?

Then again, Sentosa Express has foldable seats that are locked the entire day since it is more often than not, crowded.

I think SMRT got the right idea with the bar trains, but instead of bars, they should have utilized perched seats, and should have focused them in carriages in which the passenger loading are highest, not just in the middle of every car.

I'm not sure this is wise considering that NSL/EWL trains have a better portion of their route elevated, which may lead to stronger air-conditioning to maintain the 24 deg C temperature.

And that is exactly why I want them to have wider windows; more natural lightning in the trains during the daytime as well, which means less lightning can be used. Perhaps sensors that detect the amount of light and adjusts the light level in the train accordingly can be installed.

As for the problem of heat and air-conditioning, one solution could be to insulate the windows by double-glazing it, similar to what was done on our Hispano Habit-bodied bendy buses. Another solution is to add some tinting to block out some of the heat.

The trains already have double-glazed windows since the first stocks (C151), the only ones that do not have is ironically the Alstom Metropolis stocks (C751A NEL and C830 CCL).

Too big windows create a problem, heat coming in, and to battle that you use stronger air-conditioning, isn't that energy non-efficient? Singapore is a hot country hence they had already maximized the window size at the beginning. And the lightings that they install now are pretty bright but counting as LED they consume pretty low electric power as well..

The main concern of local trains is the air-conditioning and not lighting taking up most of the electricity. 77 kW (66500 kcal/h) air conditioning units are not small fry..

503M has been reported (SGT (http://forums.sgtrains.com/showthread.php?tid=31&pid=16134#pid16134)) having motor car offline fault earlier yesterday. Car 1503 or 1504 is the culprit.

Last week had been a wave of cross-coupling, with 043+119F, 039+057F and 201+209F as the major few. This morning 201+209F was still running as 138M, and 202+210F were spotted as new today.

Cross-couplement may mean that maintenance schedule is back on track to rectify faulty stocks, however, speed of which occurring is higher than rectification rate hence each faulty 3-car units will need to be swapped during its down-time.

Here is one example that can illustrate what may be happening.

Day 1 night, 203F and 233F were kept to the same depot. Car 1203 developed fault during the day and need to be rectified. Train separates into 203F and 204F (3-car units). 3-car 204F has no fault, so 6-car train 233F is separated (possibly by the same crew who are trained to do this task) into 233F and 234F. 204+234F is formed, while 3-car 203F goes into repair yard and 3-car 233F is placed into the stabling track.

Day 2 morning, 204+234F goes out for revenue service. Total fleet loss is only one 3-car unit, as 3-car 233F is counted as not in service. It is not possible to have a 3-car unit running on service, but its not faulty either. Playing a game of numbers.

Day 2 afternoon, repair crew finishes job on 203F, but 204+234F is still on service and cannot be called back, so 233F is taken from the stabling track and coupled with 203F to form 203+233F, another 'cross-coupled' train.

It may be until Day 2 night or several days later, depending on the seriousness of fault, spare parts and train availability for the cross-coupled trains to go back into their original formation. This measure would only be effective for a short period of time; over some time the stabled 3-car unit which has no fault but withdrawn just because of its handicap would affect train deployment.

Note: Opinion expressed about cross-coupling is not an official source from any Authority/Company. This serves only as an external analysis on what the they may be doing.

503M has been reported (SGT (http://forums.sgtrains.com/showthread.php?tid=31&pid=16134#pid16134)) having motor car offline fault earlier yesterday. Car 1503 or 1504 is the culprit.

Last week had been a wave of cross-coupling, with 043+119F, 039+057F and 201+209F as the major few. This morning 201+209F was still running as 138M, and 202+210F were spotted as new today.

Cross-couplement may mean that maintenance schedule is back on track to rectify faulty stocks, however, speed of which occurring is higher than rectification rate hence each faulty 3-car units will need to be swapped during its down-time.

Here is one example that can illustrate what may be happening.

Day 1 night, 203F and 233F were kept to the same depot. Car 1203 developed fault during the day and need to be rectified. Train separates into 203F and 204F (3-car units). 3-car 204F has no fault, so 6-car train 233F is separated (possibly by the same crew who are trained to do this task) into 233F and 234F. 204+234F is formed, while 3-car 203F goes into repair yard and 3-car 233F is placed into the stabling track.

Day 2 morning, 204+234F goes out for revenue service. Total fleet loss is only one 3-car unit, as 3-car 233F is counted as not in service. It is not possible to have a 3-car unit running on service, but its not faulty either. Playing a game of numbers.

Day 2 afternoon, repair crew finishes job on 203F, but 204+234F is still on service and cannot be called back, so 233F is taken from the stabling track and coupled with 203F to form 203+233F, another 'cross-coupled' train.

It may be until Day 2 night or several days later, depending on the seriousness of fault, spare parts and train availability for the cross-coupled trains to go back into their original formation. This measure would only be effective for a short period of time; over some time the stabled 3-car unit which has no fault but withdrawn just because of its handicap would affect train deployment.

Note: Opinion expressed about cross-coupling is not an official source from any Authority/Company. This serves only as an external analysis on what the they may be doing.

In New York City Subway terms, this could be called mismatched pairs. On the New York City Subway, trains are made up of pairs of train cars; each pair usually should have consecutive train car numbers, but this is not always possible due to various reasons (wrecked train cars, etc.), so mismatched pairs can be quite common there.

In my opinion, mismatching train cars should not be considered unusual and, as in this case, could also be a sign that maintenance work is being carried out while attempting to make sure service availability is not affected. A train should not be out of service just because one-half of it has problems when it could be hooked up to another, properly-functioning half, even if it's not its "correct" half.

Our case of mismatching train cars is already not that bad. For quite some time on the New York City Subway, I read that there was a case where train cars of two different types had to be matched up as a pair because they lost their respective proper mate in an accident. Subway car 4460, an R40M-type subway car, was hooked up to R42-type subway car 4665; you can see them in action here (http://nycsubway.org/perl/show?34388). The differences between the two types of train cars are quite obvious in that photo. I believe that pair has since been retired and scrapped.

Oh, by the way, I managed to catch a C151A train on the East-West Line sometime last week. I will do a write-up and mini-review of it later, as well as post a few photos I took.

While on this topic of non-chronological sequence pairings... I did see a Siemens EMU at the Bishan depot today that was only half a train long. The other half was disconnected as the articulated gangway was left open at one end.

On the 4G trains, managed to take 509 on the EWL this morning and 503 on the NSL this afternoon. 503 seemed okay through its run and 509 seemed flawless compared to the reports of misaligned doors, skipping stations and STARIS malfunctions a few weeks ago.

While on my way home from work on bus 980 just now, I saw two more C151A train cars, bearing the numbers 3527 and 1527, being transported by police-escorted truck along Sembawang Road.

Which sets are now in service, by the way?

The first five - 501/502 to 509/510.

I really wish they do. In fact, I think they must if they want to improve the situation on the original MRT lines.

A few things I'm asking for in the 13 new trains:

- slightly wider bodies, thinner walls, and plug doors (to accommodate more commuters)
- wider windows (think North-East Line's C751A trains)
- improved acceleration and deceleration
- shifting of grab poles from middle of car to the sides, near the seats
- maybe overhead luggage racks? These might come in useful should they be deployed on the Airport Branch Line, or if SMRT brings the Airport through-train back
- LCD screens (a.k.a. SMRT's STARIS 2) as standard
- noise-reducing skirts on the sides (I know our MRT viaducts already has some noise barriers built-in, but having skirts on them might help silence them further. Also, remember the ground-level section near Ang Mo Kio - it's in a residential area and yet has no sound barriers of any kind)
- cars with foldable seats that can be lock-closed during peak hours (similar to what Japan has)

Just to nit-pick on a old post...

"- improved acceleration and deceleration"
The C151A does have better deceleration rate.

"- maybe overhead luggage racks? These might come in useful should they be deployed on the Airport Branch Line, or if SMRT brings the Airport through-train back"
Security concerns. Of course there's some space underneath some of the rows of seats...

"- noise-reducing skirts on the sides (I know our MRT viaducts already has some noise barriers built-in, but having skirts on them might help silence them further. Also, remember the ground-level section near Ang Mo Kio - it's in a residential area and yet has no sound barriers of any kind)"
Agreed. :)

"- cars with foldable seats that can be lock-closed during peak hours (similar to what Japan has"
There's not enough turn-around time and manpower to lock them up. I think having foldable seats like those in cinemas located at the ends of each car might work better.