Atlas B40-8 with TCS AMD4...front & back headlights reversed?

[ryan_wilkerson]

I will bet this is an easy solution but this is the first time I've had this happen before so I'm curious how it happened and the best method to correct it.

So I bought a used Atlas B40-8 and installed a new TCS AMD4 decoder. Install went fine, programmed it with JMRI and put it on the layout for a test run. I had the shell off at this point. My habit is to first turn on the headlight so I do that and it comes on. So I turn up the throttle and it starts moving in the opposite direction of the lit headlight! Hmmm...so I reverse directions and the headlight turns on the other side and the direction of travel is also reversed.
So it seems the headlight is confused....when I operate the locomotive forward, the rear light is on. When I operate it backward, the front light is on.

Any idea what caused this?
What are my options to fix it?
As I said, I have JMRI so if there is something that can be done by programming the decoder, that might be the fastest path.

Thanks!
-Ryan

[railnerd]

You should be able to fix this by changing bit 0 in CV29.

In JMRI, you can program this on the "Basic" tab, with the "Normal direction of motion" pop-up.

-Dave

[sizemore]

It happens, I see it more with TCS/NCE decoders, have only seen it on the Digitrax RDC decoder.

I'm a little foggy and Dave please correct me. Before flipping CV29, be sure that forward on your controller is in relation to the locomotive cab when the shell is on. If it doesn't match you have to tweak CV29. If forward on the controller matches the orientation of the cab you just need to flip the values for the front and rear lights. I like to keep forward with the orientation of the cab, as that might drive you a little batty when consisting.

The S.

[ryan_wilkerson]

Dave and Sizemore, thank you for the advice. I messed around with it a bit more tonight...

So to get the locomotive to respond correctly to "throttle forward", I had to set:
JMRI's Basic tab "Normal direction of motion" = REVERSE
After doing that, the locomotive will actually go forward when I want forward and backward when I click backward.
That is suspicious but that seems to work.

The lights are still the opposite of the direction of travel...

In JMRI, I went to the Function Map tab and changed the checkboxes for:
Forward Headlight F0(F) from "column 1 white" to "column 2 yellow".
Reverse Headlight F0(R) from "column 2 yellow" to "column 1 white".
That didn't help.
For now, I have unchecked both of those boxes and the headlights no longer turn on in either directions. It'll be in "non-leader" status until fixed.

Any other ideas to try?
Maybe the motor is flipped?

[central.vermont]

Ryan,
I definitely believe the motor is flipped. Look at the motor and you should see some white or light grey painted on one of the motor magnets. This one should be on the bottom. If it is on the bottom them I would also go into the Remapping tab on JMRI and look for the motor column and change that to forward running also with the change of the lights.

Jon

[jdcolombo]

Ryan,
I definitely believe the motor is flipped. Look at the motor and you should see some white or light grey painted on one of the motor magnets. This one should be on the bottom. If it is on the bottom them I would also go into the Remapping tab on JMRI and look for the motor column and change that to forward running also with the change of the lights.

Jon

I agree.  I you bought it used, it's likely someone took it apart in the past and then put the motor in upside down.  Easiest fix, honestly, is to take it apart, flip the motor, then put it back together.  But you should be able to fix the headlights via programming.

John C.

[ryan_wilkerson]

Thanks Jon and john,
I took it apart tonight to look at flipping the motor. It looks a bit involved and could damage things. The motor leads are attached and look to have a certain "side" by the Atlas design so it does not look like I can do this easily (maybe there is some trick that isn't occurring to me right now).

I had another idea...I had another B40-8 (CSX) and I took it apart to compare. It had the light grey slow speed motor so I decided I would put that motor in the SSW that is causing me problems. It is designed/setup in the same way and only wants to be installed with the motor leads facing the top of the locomotive.
I ran it and it behaved in the same way as the original motor. I guess I should have expected that.

So on to poke around in JMRI for a solution....
I still have the "Basic" tab >> "Normal direction of motion" set to REVERSE.
What tab and fields should I be setting to have the lights match the direction of travel?
Seems like my changes in the Function Map tab for front and rear headlights doesn't correct it. Is there some other place?

Could I have a faulty decoder?
-Ryan

I agree.  I you bought it used, it's likely someone took it apart in the past and then put the motor in upside down.  Easiest fix, honestly, is to take it apart, flip the motor, then put it back together.  But you should be able to fix the headlights via programming.

John C.

[central.vermont]

Ryan,
There's a first for everything they say. 
I would try what I said above in the remapping tab to try. Change the settings in the motor column. This may set it to run in reverse to what you have now but coincide with the lights. If this is what happens you may need to go back to the basic tab and put it back to "Normal" running.
Not come across this problem before but as I said..........

Jon

[sizemore]

I agree the motor is in upside down however I don't think the newer motors can be flipped like the Atlas/Kato 2nd gen stuff, the 3rd gen China produced stuff has different leads.

If it were me, perform a factory reset on the decoder. Program CV-29 to 39, then program your address. Then just need to flip CV-49 (default 0) and CV-50 (default 16) to CV-49 (programmed 16) and CV-50 (programmed 0).

The problem I think is with JMRI not knowing the decoder, and using the "common" CV table values. TCS doesn't have the same CV table as Digitrax/NCE. Digitrax uses CV-33/34 for FOR/ROR (white and yellow wires), while TCS uses 49/50. Might be best to program via your DCC system and not using JMRI (not saying JMRI is bad, just have to learn the quirks).

Easy Peasy.

The S.

[ryan_wilkerson]

Thanks for the info Jon.

Sizemore, I put in CV-49 (programmed 16) and CV-50 (programmed 0) and..... SUCCESS!!!!

Thank you for the help! Now I just need to get an Ngineering beacon and get it to operate
Awesome to have such a great resource and knowledge base for such brain teasers! Thank you everyone.
-Ryan

I agree the motor is in upside down however I don't think the newer motors can be flipped like the Atlas/Kato 2nd gen stuff, the 3rd gen China produced stuff has different leads.

If it were me, perform a factory reset on the decoder. Program CV-29 to 39, then program your address. Then just need to flip CV-49 (default 0) and CV-50 (default 16) to CV-49 (programmed 16) and CV-50 (programmed 0).

The problem I think is with JMRI not knowing the decoder, and using the "common" CV table values. TCS doesn't have the same CV table as Digitrax/NCE. Digitrax uses CV-33/34 for FOR/ROR (white and yellow wires), while TCS uses 49/50. Might be best to program via your DCC system and not using JMRI (not saying JMRI is bad, just have to learn the quirks).

Easy Peasy.

The S.

[peteski]

If the decoder has more than 2 functions, why not hook up the beacon directly to the decoder function and program it to be a flashing beacon?  No need to install a 3rd party beacon simulator.

[peteski]

I hope that you are either writing down all the customized CV settings for each of your decoders (or dump all the CV values to your PC through JMRI).  The last thing you want to go through is the pain of figuring all of this out next time you need to reprogram the decoder (when it blows its brains out).  Which is probably going to happen at some point in time. 

[ryan_wilkerson]

True, I could do that. I would first like to try this though to see how it looks in person (scroll down to "Rotating Beacon Simulators"):
http://www.ngineering.com/lghting%20effects%20for%20the%20railroad.htm

If I don't like it, then I can go the cheaper route and just wire a single LED under the beacon with the simulated flash.
Here's a video of it:
http://www.ngineering.com/Rotat.wmv  (if that link doesn't work, you can click on the photo to load the video from this page: http://www.ngineering.com/rot-beacon_video.htm)
-Ryan

If the decoder has more than 2 functions, why not hook up the beacon directly to the decoder function and program it to be a flashing beacon?  No need to install a 3rd party beacon simulator.

[ryan_wilkerson]

A very good reminder. I have written a note and included it in the locomotive box.

I hope that you are either writing down all the customized CV settings for each of your decoders (or dump all the CV values to your PC through JMRI).  The last thing you want to go through is the pain of figuring all of this out next time you need to reprogram the decoder (when it blows its brains out).  Which is probably going to happen at some point in time. 

[sizemore]

In the TCS documentation it shows the pads to use (http://www.tcsdcc.com/Customer_Content/Literature/Decoders/N_Scale/Atlas_N/AMD4_Web.pdf).

Just program either CV-51 or CV-52 to a value of 36, depending on which wire (in this case pad) you choose. Make sure you include a drop resistor to cut the voltage. Be sure to wrap the exposed leads on the resistor to prevent shorting on the frame or decoder with capton tape or heat shrink tubing.

The S.