2-6-6-2 DCC Wiring Issue

[Mark W]

I wired in an NCE decoder to my 2-6-6-2 using the supplied Bachmann DCC board insert.  The Loco runs great on DCC, but the Front and Rear LEDs won't work.  I hooked the decoder to the White, Yellow and Blue for common just like my other Bachmann's but no output.  Also while the DCC board is inserted the firebox and cab light won't work on any of the settings of their switch.  I tried another Decoder that I know works and same result.

When the DC board is inserted everything works as it should.   It seems that the problem is with the DCC insert board...

Has anyone used the Bachmann DCC wiring board to wire in a Decoder. 

Thanks for any suggestions.

[CustomRCmodels]

I just encountered the same problem ...,
Experimented around for a while ,
I ended up using the DC board ,
disconnect the 2 pins for the motor-connections , ( 3+10 )
Wired the decoder to the rail-contacts ( 1+12 ) ,
Pulled the motor-connectors of from the main-board
and wired the motor-connectors itself directly to the decoder ..
Means the LEDs and firebox are always on now, which is fine for me ,
and just the motors are controlled via DCC

Willy
CustomRCmodels

[Mark W]

Willy,
Thats a great solution.  I thought of it but was afraid to try it.  In addition to getting the firebox and cab light, do you get the smoke to work on the DC setting.   What happens to the front and rear leds?

I spent over an hour on the phone with Rodney from Bachmann.  He was very helpful, but since it is so new he was going to experiment with it and let me know what he came up with.

I did get the firebox and cab to work DCC, but only at idle, when the throttle is moved the firebox freezes lit with no flicker. 

I am going to either live with a frozen ficker and wire the front and rear leds directly to the decoder with a 1K resistor,  or try your solution if the lights and smoke will work by switching them from the bachmann switches.

Thanks for your response.  I wonder if the Plug and Play guys are having any of these issues.

Mark

[StanAmes]

Mark

The 2-6-6-2 isolates the track from the internal electronics.  For the lighting and functions to work properly you need both a DC raw + and a DC raw -.

The dummy board has a rectifier on it to provide this function.

When you install a DCC decoder or RC unit you need to ensure that these connections are still made.  Many of these units have both a + and a – connection for this purpose.  Some however only provide the raw +.

If your DCC decoder does not have a ground output you can install a small rectifier using the connections on the rear of the main board.

Hook the AC legs of the rectifier to the track leads (J1-1 and J1-12), the  rectifier + to the locomotive + and the rectifier – to the locomotive -.  Once done all will work as expected.

Hope this helps

Stan

[Mark W]

Stan,

Thank you very much for your response.  I have spent all weekend trying to get this right.  I guess it make sense. I wish Bachmann would have explained it a little better. 

If I may I'd like to ask a couple of questions to clarify:

I use  NCE decoders D408SR  and I think they just have  (2) blue common  output and the  9 functions (-) and no other connections other than the motor and track connections.   I guessing I need the rectifier.

Are there any specs on the rectifier to look for, or any type ?

When you say connect the AC side of the rectifier to (J1-1 and J1-12), do I use soldierable connections on the end of the board ?

And as for the the " rectifier + to the locomotive + and the rectifier – to the locomotive -"   is that the wires on DCC daughter board labeled Train Bus (+) and Train Bus (-)  or Loco ground and Loco positive. 

I'm thinking its the Bus (+) and (-) because the Loco positive is the blue wire connected to the Decoder. 

As you can see I'm a novice at this, and I appreciate your help very much.

Mark

[StanAmes]

Radio shack sells a 1.4 amp one for $1.50, anything over a amp should be more then sufficient.

You can use the solder connections at the end of the board for the connections or use the wires on the plug in board, it really does not matter.

The Locomotive + and - are the right connections.   J1:6 is locomotive + and J1:7 is locomotive - or ground.  These connections are available in the socket or on the solder connections ar the rear of the board.

The Train Bus connections (J2:4 and 5) are for a future expansion and are not used at this time by any manufacturer.

Hope that helps

Stan

[Mark W]

Stan,
Just wanted to thank you again.  I tried the Rectifier and as you said everything works as it should.  I think Bachmann should have mentioned this in the manuals.  At any rate, thanks again.

Mark

[CustomRCmodels]

Willy,
Thats a great solution.  I thought of it but was afraid to try it.  In addition to getting the firebox and cab light, do you get the smoke to work on the DC setting.   What happens to the front and rear leds?

I spent over an hour on the phone with Rodney from Bachmann.  He was very helpful, but since it is so new he was going to experiment with it and let me know what he came up with.

I did get the firebox and cab to work DCC, but only at idle, when the throttle is moved the firebox freezes lit with no flicker. 

I am going to either live with a frozen ficker and wire the front and rear leds directly to the decoder with a 1K resistor,  or try your solution if the lights and smoke will work by switching them from the bachmann switches.

Thanks for your response.  I wonder if the Plug and Play guys are having any of these issues.

Mark

Hello Mark ,
Sorry for my late responds ,
but as I read here you got it already going ...
Anyhow ,
The way I did it , the firebox , smoke and LED's
( front and rear and inside the cab ) work on switch-position DC
the firebox flickering works just as it should ,
and it does not change with the speed of the loco ...
if I switch to DCC I lose the firebox ...
the smoke works either way , DC or DCC ....

By the way , under a different thread I asked if anybody would know of a decoder and sound chip which would install in the 2-6-6-2
as a plug-n-play ,
but so far I have not gotten a single responds to that ...
I gone try one of the aristocraft combined sound-driving-decoders ,
since they use the same pin-layout ...
At the moment I use only a cheap MRC sound-driving-decoder which actually works surprisingly well , even without using the chuff-triggers ...

Willy
CustomRCmodels