Command control switch issue

Nothing you have to do, you obviously have a short somewhere.  Try powering the switch by itself, there could be a manufacturing defect within the switch that's causing the short.

There is a common issue with these switches where the power terminals are not positioned as the labels on the bottom of the switch indicate.

You can read more about how to correct this issue on this thread, click the link below to go there:

Fastrack Switch Wiring - track jumper works but aux connection doesn't?

The switch I have hooked up to accessories post and works just fine. It has to be that it's not completing a circuit from the ends of the track. I'll have to look at the thread where you all dug into this further.

If the transformer is indicating a fault, it's because there is a short circuit between Hot and Common somewhere as John suggests.  If it's not a set of crossed wires in the connections to the switch, it's probably a short at the switch.  This is most likely due to the switch's terminals being arranged incorrectly at the factory, ie. the Aux Ground and one or both of the 2 Power terminals.

Perhaps I don't understand but if you have a TMCC remote switch you shouldn't have to wire it up to anything.  It will work just fine on track power.  I don't remember for sure but you might have to change a connection at the switch to do so-the instruction sheet shows how.  I have a number of them that work of track power just fine.

If you don't have TMCC, the command switch works just like a remote switch, the command capability is invisible to you in that case.

It's true that the CC switches should run just fine off track power.  I prefer to run them on separate power feeds at about 14VAC to promote their longevity (and to allow operating them independently from variable track voltage for conventional loco operation).  I believe independent power feeds also helps isolate them from Transient Voltage Spikes that occur during derailments, as that momentary higher voltage spike exists mainly on the track power circuit when suppressed by TVS diodes in that circuit.  Granted, a TVS attenuated voltage spike can travel back through the transformer secondary windings (if using the same transformer for both circuits), but it has a longer way to go (more resistance) than if the switch is powered directly at the track.

Just a clarification so far, I do not have the switch hooked up to track power, it's to the accessory on my cw80. So when I plug the transformer in with the throttle off, it throws the switch perfectly. It's the track connection not making the connection properly and causing the cw80 to blink like there's a derail somewhere when I power up the throttle.

@Regnildnas posted:

Just a clarification so far, I do not have the switch hooked up to track power, it's to the accessory on my cw80. So when I plug the transformer in with the throttle off, it throws the switch perfectly. It's the track connection not making the connection properly and causing the cw80 to blink like there's a derail somewhere when I power up the throttle.

Thanks for the clarification.  It still sounds like there is either a set of crossed Hot and Common wires (either auxiliary or track) from one of the CW80's outputs or with mixed up switch terminal locations.

What happens when you power the switch from something other than the CW-80 ?

What happens when you operate the switch off just track power ?

Haven't tried powering it from the track. I have a couple of other ones I power from the accessory terminal with no issues. Would see why I would need to test it out on track power since the switch is is working properly. The issue is when the track (switch) is connected, and then add voltage to the track by throttle with the transformer, the transformer's circuit breaker reads like there is connection problem, like a derailment or what not.

Fastrack Switch Wiring - track jumper works but aux connection doesn't?

If the AUX GND  and AUX power terminals in the switch are reversed (or any wires from the transformer are swapped between Hot and Common), EXACTLY what you are describing will happen.  The switch will work until you supply power from another source, which will overload the transformer because Track power gets shorted to the ground inside the switch because you are then supplying 2 out of phase AC power sources to the same switch terminal.  Please refer to the other thread I linked above for checking continuity between the switch terminals and the rails they are supposed to be connected to.