Electrical Questions on Steam Upgrade

It's probably best to treat the project as a straight upgrade and feed components per the Upgrade instructions.  For my similar upgrade last year (an early PS2 Challenger) I replaced the MUX board with a Dallee #378 VRS-Adj Regulated Power Block for cab lights and marker lamps.  This Dallee board is a constant voltage board you can run off the pickup rollers and chassis ground and voltage is adjustable.

http://www.dallee.com/PDFs/Price_list.pdf

Dad-O First I would try to figure out what made the board go. Second how do you know if the mix boards are bad? Are they burnt or something? If I was doing this I would get the 3volt board with the connectors for 5 volt. Then all you would have to deal with is replacing the speaker and battery. It would be alot less wiring. The 10k ohm resistor in the orange wire is for chuffing in neutral. This was a problem with only the 5 volt boards. The 3 volt has it built in so I would take it out. The mux boards are for increasing the amount of space for lighting and other things since there are only 10 pins.

Purple wires are hots..not grounds.

I agree with Ralph on the use of the 3V with 5V connectors.  If you use the Steam kit you are limited to head light control only.  You need to get a CV board to power firebox, markers, cab light, etc...

 

A light circuit will handle 2 bulbs, so you could double up the headlights with the cab or firebox as an example.  The other alternative is going to 18V GOW bulbs and powering them from the track voltage.

 

With these systems, + voltage is applied, and the negative is via the control FET.  PCB Ground is NOT chassis ground.  Allowing a light powered by the PS-2 board to return to chassis ground will blow the lighting FET or worse, the board. 

 

The steam kit has the least flexibility, that is why the 2 diodes are taking voltage off the motor leads to power some of the features.  The 10 pin connector for steam isn't enough.   That is why some engines had the board in the engine and/or the MUX was used.  G

GGG, Thanks for the information.   

 

Sorry for delaying reply, my wife and I were in Florida for a while. I finished the Challenger installation after we returned last week.

 

Everything tested OK, with no shorts. The only problem was that the locomotive loped along the track and at the same time the Z-4000 amperage meter fluxuated up and down more than I thought it should. (Between 1.2 and 1.8 amps at about 20mph) I tested it on stationary rollers and found the rear motor drivers were the cause. I took the rods and eccentric crank off of the rear drivers, both sides, to test further. I found that the "inner sleeve" that the eccentric crank goes through was missing on the right side drive wheels. I "borrowed" one from my RK N&W "J" (same size) to test and re-assembled everything.  Now the Challenger runs smooth and the amperage stays steady.

 

I loaded the proper "sound set" into it yesterday (Sun.) and it sounds and runs great. Another one brought back to life.

 

Thanks again to all that contributed information.

 

Dad-O

 

The N&W is alive and well, running in Rhode Island

GOOD JOB!  G