J325 with Dynapath 20 - control OK, servos won't start

[specfab]

I have a Journeyman 325 with Dynapath Delta 20 control that I bought a few years ago. It was functional up until mid-December last year; good one day, the following day could not get the drives to start up using the Reset button on control. I am running power from a 10HP RPC that came with the machine from previous owner, where the outputs are about 240V for the two pass-through legs, and about 265V for the generated leg. This machine has the input power separated between control and servo cabinet, so that the control cabinet uses the two 240V pass-throughs and the servo cabinet sees all three legs, entering through the 3-phase input circuit breaker on the machine. It appears that the 3-phase breaker is tripping immediately at startup of the machine, which would seem to be the reason the servos won't start from the Reset function.

The circuit beaker is a shunt-trip unit, with a couple of wires running 24V from "somewhere" to the shunt coil. My main questions are these:
-- What is the normal state of the shunt-trip coil when in operation, energized or non-energized? My assumption is that it should not be energized, but that is just that - an assumption.
-- What is the immediate upstream source for the 24V that feeds the shunt-trip coil? My documentation for this machine is not as complete as I would like.

The power being supplied appears to be over the tolerance for the machine specs, at least for the generated leg, and I need to address that. It may be the cause for the problem, but I would like to eliminate as many ancillary components as possible from the list. Replacing the circuit breaker is about a $600 exercise, from what I've gotten from electrical distributors, so not an easy experiment. Any help appreciated --

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[machinehop5]

...may want to check your VFD for dead short with meter. or try disconnecting the VFD than see if, the breaker trips

[specfab]

...may want to check your VFD for dead short with meter. or try disconnecting the VFD than see if, the breaker trips

Thanks for the response -- At the risk of sounding like an idiot: I assume you are referring to a VFD within the Tree system(?) My input power is coming into the Tree from a rotary phase converter. If this is an onboard VFD, is it labeled as such on the typical Tree schematics?

[machinehop5]

...yes, the Variable Frequency Drive aka Spindle Drive is the only thing besides the Coolant Pump that is 3 PH.

[Jim Dawson]

Energized trips the breaker. I have the same thing on one of my machines as a safety lockout, trips the breaker if the panel door is opened with out setting the bypass lockout. In my case I just disconnected it.

[specfab]

Thanks to both Jim Dawson and Machinehop5 -- I have yet to get back to this machine for additional troubleshooting, but your information is useful. The schematic Machinehop5 posted is indeed the one I have, and now I have at least some idea of what to try for the next steps.