Large Scale Central

NW-2 wiring questions

General Discussion
#1

Good afternoon gentlemen. I again need a little help, this time with the wiring of a USAT NW-2. I am trying to install an Aristo Revolution receiver. The wiring between the two main circuit boards seems a little strange, and I am not sure I understand what is going on there. I was hoping to be able to install the Revo without having to butcher the wiring, in case I wanted to switch back, but maybe that is not feasible? I hope to be using track power, and also install a Dallee sound board, if I can squeeze everything into the NW.
My main question is, why there are THREE wires to supply voltage to the motor blocks, instead of TWO? We have a green wire to one side of the motor then blue and yellow wires to the other side. Do we have to cut the wires to the motors and connect the green wire to one side of the Revo and the blue & yellow wires to the other side? Or, is there an easier method?

PS: Forgot to mention, if anyone has a schematic or a link to one, it sure would be appreciated.
Thanks
George

#2

George - I don’t have an NW-2, but I did a complete wiring trace of a USA 44 Tonner and created a diagram some years ago. I don’t know if this will help or not.

(http://photo.cvsry.com/USAT44T-640.JPG)

While the loco in the drawing has 4 wires to each truck, and only two to each motor. Are you sure that all three wires connect to the motor ? I’m thinking they might be trying to use a common wire someplace to save a few inches of copper.

#3

Mr Radder, thanks for the reply. There are two more wires to the motor, one each of RED & BLACK that are for track voltage pickup. That would make a total of five wires for each motor block. I can see where they are attached, near the wheels. The other three wires are plugged into the ends of the motors.

#4

I do believe,unlike other USAT locos, the NW2 did have three wires going to the motor(s).
I don’t know why, but, I suspect the third wire was in place possibly for use as part of a method of motor “noise” suppression. I believe only two wires are actually connected inside the trucks to the motor terminals.

#5
TonyWalsham said:
I do believe,unlike other USAT locos, the NW2 did have three wires going to the motor(s). I don't know why, but, I suspect the third wire was in place possibly for use as part of a method of motor "noise" suppression. I believe only two wires are actually connected inside the trucks to the motor terminals.
Should be fairly easy to test Tony's theory with a multi-meter on ohm scale. Iy you find a fair amount of resistance between two wire, that is likely the motor. Very little or no resistance is probably non-connected wire.

And George - Please call me Jon. Mr. Radder was my father :smiley:

#6

I did measure a few ohms between the outside yellow and green wires, and applying power to them alone, runs the motor. The blue wire seems to have no function. So, guess I will simply ignore the blue wire from the plug and continue on. Unless someone has any information I may be missing.

I finally called the factory, which I hate to do, because I never get a satisfactory answer from them. The technician I spoke to, said they NEVER made a motor block with FIVE wires. “I must have an engine modified by someone else.” But it looks like factory wiring inside, with factory installed circuit boards and a 3 connector plug/socket connections between the motor block and the boards. The motor block looks like a standard motor except it has 5 wires instead of 4. And, no they do not have any schematics either.

Jon and Tony, Thanks for your help.
George

#7

They did make it.

It was the first one they made and the 5 wire cabling has never been repeated as far as I know.

#8

Hmmm, sounds like you know more about the USAT product than the manufacturer does.

George

#9

Heck George everyone knows more than the manufacturer’s didn’t you know that??? Hee hee Calling them is an act of total frustration, on most if you even get an answer back. I’m still waiting for a call back from the Polky man from 2-3 months ago. Solved my own problem!! Regal

#10

That’s why I tried to get an answer here first Jerry. I have had a few problems with Aristo also. Nothing major, just irritating and asnine questions and unsatisfactory answers, or no answer at all. But it doesn’t matter, I usually find the answers to my problems by searching through the forums.

George

#11

Yep the “polkyman” needs to poke his customer service, and get em to wake up and smell the diesel smoke or roses or whatever, and take care of their customer service support area big time me thinks!! Regal

#12

It’s interesting that you bring up the lack of customer service from that manufacturer. I’ve ordered replacement parts from USA and LGB Silvergate and have been offered really worthwhile advise to help solve my problems as well as really quick delivery on the parts. The other guy consistently loses my order,claims I never ordered anything,tries to make me vanish when I take advantage of their sales promotions. They seem to like to take an attitude with you too.

#13

I don’t know whether or not I know more than the manufacturer in general, but, I have just had a look back through my old (last modified in August 1997) RCS instructions filed in the deep dark recesses of my computer, I can assure you the installation kit I designed and produced specifically for the NW-2, has three wire plugs and sockets between the loco wiring and the motors in the trucks.
They are Green / Blue / Yellow. The Green and Yellow wires go to the motor terminals. I used the Blue wire to connect the motor case to ground on the system wiring with .1mfd (#104) monolith caps from the motor terminals to the blue ground wire.

#14

George,
This summer I installed a Revo in a USAT S4 and GP7. IF the NW2 is wired like them, there are black connectors plugged into the main board. The connectors with 2 wires supply power to the motors and the connectors with three wires are from the track power pick up.
You can buy the same connectors from All Electronics on line. Part # is conn-240.
You use the connectors to take the track power to the Revo, then the motor outputs to the loco’s main board. Simplest way but I would not run the smoke units, might be too much of a current draw for the Revo (Does the NW2 have smoke? I have one but forget)
If you want to run everything off of full track power use a connector strip. Run track power to the strip, then both to the Revo and main board. Revo motor outputs to motors.
Just watch the color coding. Front block wiring is red positive, black negative. Rear block wiring is black positive, red negative, due to the rear motor block being mounted backwards.

Using the connectors you do not need to cut any of the original wiring.

#15

Ward.
The track pick up connectors actually have four wires not three as you describe. Two go to the side frames (one each side) and two go to the skates in the trucks (one each side).

The early NW-2’s which George says he has, have a THREE wire connector to each motor block from the internal USAT wiring.
They are Green/Blue/Yellow and are different from all later USAT locos, which became two wires, Black/Red.

#16
Ward Hutton said:
George, This summer I installed a Revo in a USAT S4 and GP7. IF the NW2 is wired like them, there are black connectors plugged into the main board. The connectors with 2 wires supply power to the motors and the connectors with three wires are from the track power pick up. You can buy the same connectors from All Electronics on line. Part # is conn-240. You use the connectors to take the track power to the Revo, then the motor outputs to the loco's main board. Simplest way but I would not run the smoke units, might be too much of a current draw for the Revo (Does the NW2 have smoke? I have one but forget) If you want to run everything off of full track power use a connector strip. Run track power to the strip, then both to the Revo and main board. Revo motor outputs to motors. Just watch the color coding. Front block wiring is red positive, black negative. Rear block wiring is black positive, red negative, due to the rear motor block being mounted backwards.

Using the connectors you do not need to cut any of the original wiring.


Yes the motor does have three wires to supply power from the circuit boards. I think it is probably a good idea to buy matching connectors from All Electronics rather than butcher up the wiring, in case I decide to restore it to standard track power. I have disconnected the smoke units, since they don’t work well outside, I never use them anyway. Still trying to decide if I need to use the third (blue) wire.

George

#17
TonyWalsham said:
I don't know whether or not I know more than the manufacturer in general, but, I have just had a look back through my old (last modified in August 1997) RCS instructions filed in the deep dark recesses of my computer, I can assure you the installation kit I designed and produced specifically for the NW-2, has three wire plugs and sockets between the loco wiring and the motors in the trucks. They are Green / Blue / Yellow. The Green and Yellow wires go to the motor terminals. I used the Blue wire to connect the motor case to ground on the system wiring with .1mfd (#104) monolith caps from the motor terminals to the blue ground wire.
So what you are saying is you grounded the motor case to your circuit board through the cap. If I was to try this with the Revolution board, I suppose it could be connected to the Revo board common ground, pin 7 on the auxiliary plug? And what does this do, possibly eliminate motor noise?

George

#18

George,

My initial comments were to correct the impression given to you by USAT that the NW-2 loco had been modified by a previous owner.
It had not. That is the way the early ones came from the factory.

Yes I did use the blue wire as part of a motor “noise” suppression method which is required with 27 MHz R/C.
You do not need any motor “noise” suppression with the 2.4 GHz R/C Digital Proportional R/C I am now using.
I cannot speak for what the REVO may or may not need.

#19

Tony,
Thanks for correcting and updating me.

George,
The Revo should not need motor noise suppression added. The big advantage to using the 2.4GHz freq. is that it is not affected by motor noise.
I would not connect the motor case to the aux function ground.
With the green and yellow wires powering the motor, they should connect to the Revo motor outputs. You should then only need to connect power pickups to “power in” on the Revo.

#20

OK, thanks to everyone for your help. I will put this project aside for a while until I can get connectors from All Elect.

Next project will be attempting to install MyLocoSound into Thomas. I will be watching to see if anyone posts details and photos of their efforts.

Thanks
George