Installation in a Bachmann DCC GP9

[Pequeajim]

Any hints as to the best way to install a Ring Engineering LM-3S module in a Bachmann DCC, (no sounds) GP9?

There is an 8 pin plug in it, but I want to get the lights as well as adding other lights to the engine.  I'm using this as a learning task for me.

Thanks
Jim

[Pequeajim]

Here is a pic of the frame with the shell off.

[G8B4Life]

Well you've got two choices. Harness or hardwire.

With a harness you'll get the front and rear light directly to the factory lighting board. Any extra lights you'll need to wire up yourself using the extra wires on the 9 pin harness (see next paragraph) and also the 6 pin harness for the LM (included with sound LM's).

You'd need a 9 pin to 8 pin harness. Plenty of those on the market and a quick search of websites from TCS, Digitrax, NCE, Soundtraxx etc should give a lot of different harness length options.

With a hardwire install, you'll need to discard the factory lighting board and wire up everything yourself, but you will give yourself some extra room by doing so; though it appears that there might be ample room for a harness install anyway.

I see a couple of RF chokes on the factory lighting board. If you do a harness install keeping the factory lighting board those chokes will likely have to be removed. There may be a capacitor wired across the motor too that will also likely need to be removed.

- Tim

[Pequeajim]

Thanks Tim, I'm swinging over to Yankee Dabbler this morning to try to find the part.

[Pequeajim]

With a harness you'll get the front and rear light directly to the factory lighting board. Any extra lights you'll need to wire up yourself using the extra wires on the 9 pin harness (see next paragraph) and also the 6 pin harness for the LM (included with sound LM's).

I choose the harness option...

You'd need a 9 pin to 8 pin harness. Plenty of those on the market and a quick search of websites from TCS, Digitrax, NCE, Soundtraxx etc should give a lot of different harness length options.

Picked up one from Yankee Dabbler today.  I plugged it in and it going the LM3s, however, it failed on the load test.  I could not get it to move at all.

With a hardwire install, you'll need to discard the factory lighting board and wire up everything yourself, but you will give yourself some extra room by doing so; though it appears that there might be ample room for a harness install anyway.

I thought that I would just use the front and rear directional lighting until I setup the loco, then hard wire anything else I need.

I see a couple of RF chokes on the factory lighting board. If you do a harness install keeping the factory lighting board those chokes will likely have to be removed.   here may be a capacitor wired across the motor too that will also likely need to be removed.

Could this be affecting the speed control?

[nodcc4me]

Jim, try unplugging the 8-pin from the board and reverse it. That shouldn't make a difference but I have found that in some locomotives the headlight will only work if it is plugged in a certain way. Maybe you'll get lucky but those boards are usually plug and play. If you are going to add lighting later, you will most likely have to remove the board and hard wire it.

[Pequeajim]

I thought I did try rotating the plug 180° if you're looking down on it witchwood innocence reverse everything. It looks like the NMRA standard is such that if it's reverse it's not going to hurt anything so I'll try again.

[G8B4Life]

Rotating the plug 180° will do nothing as the orientation of the plug has nothing to do with RF suppression.

The RF suppression (inductors and capacitors) most definitely can cause issues, and seems to cause more of a problem for RailPro LM-x's than it does many DCC decoders, possibly because RailPro uses a much higher frequency to drive the motor than some DCC decoders.

Personally I'd remove all the RF suppression components (the two inductors and the capacitors) but I have read that just removing the capacitors will suffice. According to this Soundtraxx document (http://www.soundtraxx.com/documents/appnotes/bachmann_gp9.pdf) the capacitors are attached to each motor lead. Try removing just them first and see if everything improves, if not then you'll need to try removing the inductors as well. If you remove the inductors you'll need to jumper where they were with a short piece of wire.

- Tim

[Pequeajim]

Thanks Tim.  I will give that a try.


Jim

[Pequeajim]

Worked!  Now to just add the sound.

[Cade1989]

Your best bet is to hardwire on the Bachman’s locomotives. I tried installing one of my modules on a Spectrum Dash 8-40CW and it didn’t play well with the factory Bachmann board. If the loco has LEDs, unsolder the resistors from the board and you could use those. If you do hardwire, make sure you get rid of those yellow capacitors that are attached to the motor.

[Pequeajim]

I think I will have to do just that Cade1989 as the loco shell does not sit all the way down because of the thicknesss of the LM,  so I can't mount the couplers.  I was looking to convert several engines quickly to build up my RailPro fleet, but if I cant get the shell to fit, it might be time to get the Dremel out, or just put a LokSound in it.

Jim