Lionel AMC2 and problems with Common Ground

@LionelAG posted:

Dave/Lionel-

I'm a pretty broad user of Lionel LCS and have most of the modules.  I had never used the Lionel AMC as I didn't really have a need but decided to give it a try for Light Control across my layout.  So I picked up the new AMC2 recently and, standalone, it seems to work fine.  I did see one report of it not working for an Atlas Turntable but no confirmation on that.

So, as I said, by itself with no interconnections with other items all checked out.  This weekend I decided to economize some wiring with common ground and took a feed off of an ASC2 and AMC2 for control lights/gate activation/elevator activation on a non-tmcc Log Loader.  Powering both the ASC2 and AMC2 from a single accessory transformer, I wired things up according to the labels and owner's manual.  ASC2 was fine but when I tied in the AMC2 with common ground I got a short.  After checking all my wiring, it turns out the Lights/Motors side of the box is mislabeled; COM is actually + and 1/2/3/4 is Common.  So the board itself is still fine.  The physical terminal assignments (positions) on the AMC2 are all consistent with other LCS modules, BUT the module label on the box is wrong and the entire Owner's Manual is written according to the incorrect module label.  The PDI/module pwr side of the box is labeled fine and consistent with other LCS modules.

Additional Request:  Assuming Lionel is going to correct the label, it would be helpful to number the Motors/Lights banks to match the programming order of each terminal of connections.  i.e. Motors are programmed/operated via Aux1, 1 and Aux1, 2; Lights are programmed/operated via Aux1, 3 and Aux1, 4 and Aux1, 5 and Aux1, 6.  Please just label them Motors 1-2 and Lights 3-4 rather than Motors 1-2 and Lights 1-4.  Also, please correct the Owner's Manual to correct the mislabeled terminals.

I would contact Lionel directly about this.  While it's good knowledge to share here to make sure Lionel sees the issue it would be prudent to send it directly.  You can also use the @Dave Olson to see if he has any insight to what you are experiencing.

I could not get it to work with an atlas turntable - going to try again - did you find the input power A-U's labeled correctly - thanks for the information

ted

@ted K posted:

I could not get it to work with an atlas turntable - going to try again - did you find the input power A-U's labeled correctly - thanks for the information

ted

A-U's are labeled correctly.

The statement above that is struck through turned out to be incorrect.  The A/U must be swapped as I put in my edit.

@MartyE posted:

I would contact Lionel directly about this.  While it's good knowledge to share here to make sure Lionel sees the issue it would be prudent to send it directly.  You can also use the @Dave Olson to see if he has any insight to what you are experiencing.

Done.  Just sent to Dave.

EDIT/CORRECTION:

Okay, so I didn't finalize wiring on the "revised" AMC2 wiring last weekend.  Today I proceeded to wire things up on the Lights/Motors side of the AMC2 per my notes above using common ground.  However, now I have a constant light; the part that I was trying to vary for the lights in the Log Loader.  Well it turns out that the label posts must be followed on the Lights/Motors side as the variable voltage circuit in the AMC2 is on the '+' pole of the Lights/Motors.  Using common ground as I described earlier effectively cancelled out the variability of voltage provided by the AMC2.  So I must revise my earlier statement with...

If you expect to use common ground with the current AMC2 system, you must swap the 'A' and 'U' ports on the opposite side.  Simpler change than what I suggested but not in line with other LCS Modules.  Swapping A/U allows you to use the wiring labels and post assignments as they are.  No changes to documentation for the Lights/Motors side.

Having 'A' be common is just wrong though.