Finally adding pickups to a couple tenders and have two questions. A PTC isn’t like a capacitor, so it doesn’t matter which way it is wired into the line. Correct? And I seem to remember from somewhere that the new hot wire to the engine should be accompanied with a new ground from the tender. Can’t see why this is necessary. Is it different if adding a pickup to a new command control installation in the tender versus one that just has a conventional electronic reverse unit located there? Thanks.
The PTC has no polarity, you are correct. The new ground isn't really required, typically it's the center rail pickups that are the issue. Obviously, if you happen to have an 0-4-0 and use insulated rails, you might want to add the ground line as well.
Thank you , sir. I was wondering something else. Is it "convention" that on four or larger tethers between engine and tenders that the two outside wires are the power and common ones?
No, not at all. Typically, on the MTH PS/1, Williams, 3rd Rail, etc. the two inside leads are power and ground and the two outside leads are the motor. For tethers with more than two wires, I don't know of any "standard".
Thank you. Good to know.
FYI, you should always check before you assume that "standard". Though It's fairly universal, I'm sure a few people have violated it over the years.