TGW power unit w/ 2 motors

[cteno4]

this is an interesting one! tgw is releasing a Kiha 40000 sized power unit with each truck having its own vertical mounted motor. looks like it does leave more open window space in the center and the motors dont go up all that high and perhaps can be hidden better nearer the ends than in the center of the car! not cheap at $53, but as they said on laugh in, very interesting...

 

http://www.1999.co.jp/eng/10152640

 

cheers

 

jeff

[clem24]

this is an interesting one! tgw is releasing a Kiha 40000 sized power unit with each truck having its own vertical mounted motor. looks like it does leave more open window space in the center and the motors dont go up all that high and perhaps can be hidden better nearer the ends than in the center of the car! not cheap at $53, but as they said on laugh in, very interesting...

 

http://www.1999.co.jp/eng/10152640

 

 

I've always wondered about this and any other train that has more than 1 motor car - I can only assume the wheels will wear faster because there's just seemingly no way to sync them perfectly and because they just don't have enough weight on them, wouldn't one set of wheels always spin out of sync if the motor is not perfectly identical? And even then, wouldn't there be slight variations in how fast the motor spins in relation to how much voltage it receives?

[cteno4]

yes i would think so, but with some weight the loads on the motors may equalize out small variations. i doubt it would lead to a lot of wear on the wheels though, would take a lot of running to grind the track or wheels much i think. hopefully they cross wire the motors so that they both get the same power all the time from both trucks. tgw has been doing these little truck motors for its small engines so this is a next logical step to leverage their current technology. im guessing this has not been around as much as motors have only recently really shrunk down at cheaper costs.

 

the cool thing is this unit will be pretty easy to lengthen or shorten to fit models! just whack it in the middle, no drive shafts to worry about!

 

i am sort of tempted to get one to just see how it works, but a $53 test is a bit expensive...

 

cheers

 

jeff

[keitaro]

It will mainly cause derails and broken couplers.

 

I.e If you have 2 M cars connected together and one stops due to dirt on the track it leaves the other one pushing / pulling.

 

If they are going a decent speed when this occurs the pushing scenario will usually end up popping the car of the track similar to when you push a motor car yourself the wheel pops up and off.

 

If it's the pulling scenario the motor car can't pull the other motor car as the wheels don't spin freely like they would on a non powered vehicle. If they had a fast speed at time of other car jamming up it can break the more flimsy coupler.

 

Other derailments you might experience is derailments at tight curves and start of hill inclines. due to the rear car pushing faster and harder against the one going up the incline or pushing more force at a tight curve.

 

I ran my kiha 110 x 2 motor cars together and that is exactly what happens, only some times though some times i can get a solid 15 mins - 20 mins no issue and others happens with in a few mins.

 

Although it is still fine to run them together these things can and will occur.

[cteno4]

keitaro,

 

these are not the same issues as with this unit as the two motor units are in the same car, each truck has a motor.

 

running two separate motor cars can cause the issues you mention, but i have quite a few two motor car trains (12/16 car shinkansens, double shinkansens, and some larger express trains) and rarely have an issue with two motor cars you describe unless one motor car is really having trouble. ive long wondered if a drive shift might be stripped if one car lost power suddenly, but ive never had this happen. i have had a couple of drive shafts snapped, but these have so far been single motor car trains.

 

i have never seen a broken coupler from multiple motor units.

 

cheers

 

jeff

[The_Ghan]

I'm guessing, but it would make sense for the two motors to share common pickups, which would minimise the problem proposed by Keitaro.

 

Cheers

 

The_Ghan

[cteno4]

the problems that keitaro mentions wont happen with the TGW unit as both motors are built into the same motor car, not two separate cars. the worst that would happen is what clem mentions that if one motor/gearing is a bit faster than the other one truck's wheels will slip some.

 

im guessing they do have pickups on each side and those are cross-linked to minimize any difference between the two motors. also i expect the load on the bearings, gears and motor might keep them pretty much in synch. the kato unitram does the same thing of having motors in each of the tram's two trucks.

 

cheers

 

jeff

[Martijn Meerts]

Having multiple loco's/motor cars shouldn't be much of an issue either, or at least, not if you're running dcc. You just need to make sure to set up the decoders so that the speeds for each speed step match up. It's something that needs checking and re-checking regularly.. Miniatur Wunderland for example has a train that has a total of 5 locomotives. 3 up front and another 2 in the middle of a string of freight cars (total length about 15 meters). All these loco's are powered, and the train pretty much never derails or causes issues, and it's been running for several years on a daily basis :)

 

With DC it can be more of a problem, because you have no control over the way the motors behave at all. That said, Tomix has been putting out trains with multiple powered cars for a LONG time, and I can't say I've heard many complaints...

[cteno4]

yes but its a different issue with the tgw motor car, its a single motor car with two motors, one in each truck so different story than the multiple motor cars.

 

in the other story of multiple motor cars, with DC you can use resistors to slow up faster trains to match things better (not as clean as dcc, but works!). that being said i have a lot of double motor car trains that run fine with DC. traction tires might also help synchronize the loads once two cars are connected together. this is an old old issue with multiple engines in dc world and things usually work fine with them w/o any modifications.

 

cheers

 

jeff

[keitaro]

heh mis-read that thought you were reffering to cars my bad.

 

I think this is also done and can be done in world craft / world kougei models

 

example motor http://www.1999.co.jp/eng/10139108 you can put on both sides.

 

always wondered about as a last resort adding these into and old model tomix / kato etc with some modification of course. If you can't get spares.

 

example model http://www.1999.co.jp/eng/10114424 if you look at the picture you can see the motor on both sides. If you look at the TGW unit it loks as though it's just a world kougei item.

[cteno4]

havent seen anyone sell a power car with each truck separately powered as a bare motorizing unit. the worldcraft and the kato unitram are the only ones i have seen do this in n scale models. world craft does it in their kits by just having two of their power units (which they sell separately) that just pop in to a length of plate to form the connecting chassis. simple and clean way to assemble it to exactly the sized needed in a model! world craft cross wire the motors in their models.

 

http://www.1999.co.jp/eng/image/10108854z2/70/2

 

cheers

 

jeff

[keitaro]

hows this go for dcc?

is it difficult to do?

do you just put the 1 decoder in the middle on the wires?

or would it need to be 2 decoders?

[The_Ghan]

One decoder should be fine.  I would need to see the wiring diagram in order to confirm placement. 

 

Cheers

 

The_Ghan

[cteno4]

Frpm the looks of the tgw there are two wires going up to each motor so the motors look isolated so you could just need to wire the wires from both trucks to the decoder input then the output to the motors. mind you this would give the same power to both motors and hopefully they will function close to each other in speed. could be ultra fancy and wire a decoder to each and try and speed match each motor using the decoder speed table you could make up for each.

 

cheers

 

jeff

[keitaro]

Frpm the looks of the tgw there are two wires going up to each motor so the motors look isolated so you could just need to wire the wires from both trucks to the decoder input then the output to the motors. mind you this would give the same power to both motors and hopefully they will function close to each other in speed. could be ultra fancy and wire a decoder to each and try and speed match each motor using the decoder speed table you could make up for each.

 

cheers

 

jeff

 

how hard would that be to match up haha can't exactly test them seperately lol.

[marknewton]

I've always wondered about this and any other train that has more than 1 motor car - I can only assume the wheels will wear faster because there's just seemingly no way to sync them perfectly and because they just don't have enough weight on them, wouldn't one set of wheels always spin out of sync if the motor is not perfectly identical? And even then, wouldn't there be slight variations in how fast the motor spins in relation to how much voltage it receives?

 

I can't see this being a problem. There's been many O scale models over the years that are powered this way, and I'm not aware of any great dramas with them. A mate of mine used a similar two-motor Atlas mech to power one of his diesels, which has put in many hours of running at exhibitions, and it has performed flawlessly.

 

I'm going to order one of these, as I think it would have great potential for powering a HOn30 model I've been toying with, so I'll report back in due course.

 

Cheers,

 

Mark.

[cteno4]

im betting they have a little clip of some sort that holds them into the chassis (take a look at the world craft instructions and how they do it, betting tgw did something similar). so pop out the trucks/motor units and just wire each up on its own decoder and put down two parallel stretches of track and race them till they are perfect! remember to orient them in reverse to each other though!

 

i do wonder if everything is symmetrical in their design as the trucks are running in reverse orientation to each other (ie one forward and the other in reverse) this could make for a good difference in speed between them. this is where the dcc power curves could come into great use! can you set up different forward and reverse power/speed curves with dcc or do you just have one for both?

 

cheers

 

jeff

[cteno4]

oooh with HOn30 you could really make the motors disappear!

 

jeff

[marknewton]

Yes, Jeff, that's what I was thinking. Not only does it have potential for powering EMUs,

 

 

but I  think it could also be used under one or two 762mm gauge steeplecab locos that I'd like to build one day.

 

 

Cheers,

 

Mark.

[clem24]

I can't see this being a problem. There's been many O scale models over the years that are powered this way, and I'm not aware of any great dramas with them. A mate of mine used a similar two-motor Atlas mech to power one of his diesels, which has put in many hours of running at exhibitions, and it has performed flawlessly.

 

Yeah but that's 0 scale.. There's enough weight on the car. I think in N scale, there just isn't enough weight to ensure that each motor car won't be spinning their wheels freely. At least that's what I envision.

[Martijn Meerts]

I know there's N-scale models that use 2 motors. Often in locomotives like the EH500, the European brands tend to throw in 1 motor per locomotive part.

 

The "problem" I see with 2 motors, or more specifically 1 motor per bogie, is the lack of flywheel. Not an issue when using DCC, but the running characteristics of loco's with flywheel are just so much better than those without flywheel when running DC.

 

I don't think wheel spin is an issue. The motors are always exactly the same, and get the same amount of wear over time. Under normal circumstances it's not possible for 1 motor to not get power while the other one does, so that's not a problem either. Should 1 motor break down though, you're pretty much forced to replace both, otherwise they won't be in sync anymore.

[marknewton]

Yeah but that's 0 scale.. There's enough weight on the car. I think in N scale, there just isn't enough weight to ensure that each motor car won't be spinning their wheels freely. At least that's what I envision.

 

You might be right, but the only way to be sure is to "suck it and see", which is why I've ordered one. But given that the motors will be much smaller and presumably less powerful, the ratio of power to weight ought to be about the same? I'll happily admit to being no expert on the subject... 

 

Cheers,

 

Mark.

[clem24]

I know there's N-scale models that use 2 motors. Often in locomotives like the EH500

 

The EH500 uses 1 motor... A shaft runs into the adjacent car to power its wheels.

[Martijn Meerts]

Clem, I know that, but read (and quote) the rest of the sentence as well, where it says that the European brands often use 1 motor per locomotive part :)