Running 2 motor cars on the same consist

[Eurostar25]

Just interested to hear people's observations or tips regarding running 2 motor cars in a single consist.

I'm planning on purchasing a Kato 10 car Joban set but would like to run the full 15 cars which will require the 5 car add on with the motor car included.

 

My question is do the cars pull at different speeds I.e does one draw more power/amps than the other and if so what's the best way around it? DCC both units? Does othe front car drag the second motor spinning at a slower speed?

 

I noticed my E7 Tomix shinkansen also has a 2nd motor car in the consist although I only have 6 of the 12 cars thus far.

[katoftw]

The should to everything evenly.  But in saying that.  Small differences in manufacturing or run times means the can be different.

 

I run 2 3 car 813 units together sometimes.  At best with the 2 motor units running, they may get a little noisey, but that is about it.

[HantuBlauLOL]

Back emf based controller might help stabilizing both MC's speed.

[Ewan.in.gz]

On analogue control, I have run full consists of Kato E2s or E4s coupled with E3s, as well as 2 full E4s coupled together, and had no problems. I think that combining the weight and dynamics of all the rest of the cars and the fact they are all coupled together cancels out any differences in the power cars.

[Eurostar25]

Thanks for the comments. I was planning on just using the standard kato power pack to run them on, trying to avoid the cost of DCC at the present time if I can!

[kvp]

 

Back emf based controller might help stabilizing both MC's speed.

No, the controller would just get confused about the speed of the motors, since it couldn't get a clear signal. Some backemf controllers even get confused by the flickinging of the interior lighting on bad contact spots.

 

For analog control, my suggestion would to be use matched motors if possible, that have the same speed range. If one is slightly faster or slower, then the differences will equalize out, like in case of two differently loaded real motor cars running in the same consis that are controlled by manual speed step control. Any controller is good for them, that has a nice uniform power pattern, like any Kato, Tomix or other non feedback power packs.

 

For digital control, you have to use a decoder for each power car and set matching speed curves in every decoder. The decoders can be a backemf or a simple feedbackless type.

 

For completly unmatched motors, like a slow speed drive and a high speed unit, it might be impossible to match their speed, but they can still be run together if both units have a free turning drive, so no screws or other locking transmissions. This allows the slower unit to be trailing and only helping the faster one if it gets overloaded and slows down. This is normal for 1:1 scale trains and ride on modells, so the trains are movable with their motors turned off, but not common for smaller scales like N.

 

Unmatched motors with locking transmissions will result in derailments and pileups, because one motor can't turn fast enough to clear the way from the faster one, so it's wheels will be dragged if there are no traction tires or essentially brake the whole train if it has enough adhesion. In this case the motors can be matched (the faster one slowed down) with analog speed regulating circuits on board of the motor cars, like diode pairs, matched resistors or other active circuits.

[HantuBlauLOL]

Oh, sorry.

 

Another idea: Put a resistor inside the faster car, put it in series with the motor.

[railsquid]

I can only report that I own 2 (two) Kato Kokuden sets (yes, I was young and naive when I bought them, but have plans, but anyway..) and they run fine coupled together.

[cteno4]

Most of the times when you have two motor cars in these longer train sets they are close enough that they run great and everything evens out. I have had no problems even with the combo shinkansen setups like e2/e3 e5/e6 etc in the past even though the individual trains are not quite speed matched. The only time I have had issues is when ones either gets gummed up or looses lubrication (some come barely lubed and go dry after a while of decent running). Then you get issues. But usually you can hear the offending motor car either whining or grinding and it then is just a tear down, clean out and retuning and everyone is happy again.

 

Jeff

[E6系]

Hello,

 

No matter what you do, you will never match the speed between the two motor cars, even with DCC and a lot of programming of the decoder.  Just when you think you've got it right, put them both on the track 1m apart and run them for 5 or 10 laps.  You will see a noticeable change in the spacing, but not to worry because this happens in the real world too.  Generally, if your consist has two or more motors there should not be a problem unless one of the motors fails.

[cteno4]

E6 San,

 

Very good point! This si when I've most seen stripped driveshafts on the good engine of a pair on a longer train when one has failed and this locked up.

 

Jeff