I meant after the circuit breaker/overload device attached to the contactor.
One thing. I see you are using a single phase buck boost. I have had nothing but problems trying to use an autotransforming buck boost. They cause 2 things that I see.
1 they dont alter the voltage on one leg at all. All the bucking is done to one leg of the single phase. Making your voltages all screwey.
2 they make that bucked leg sag like crazy under load. Mine said it could deliver 108 amps at the configuration I was running it.
I have tried both with my 10hp and new 15 hp RPC. Finally said enough and now am looking for 20kva 3p 240-208 type. Because I too see 250 volts from my utility and Fanuc regen to line makes my butt pucker.
You have something going on with your hydraulics, not electrics.
Does it ever even reach a "idle " state?
The pumps that are used here throttle themselves based upon flow demand. Low flow required, the pump throttles down but maintains pressure.
You could plug all four of the collet closer hoses in your case and it should not present any more load than normal.
And you keep referring to "open" as it is some different state than closed.
The push and pull states of the closer present the same work to the hydraulic system. It is a double acting cylinder. There is always collet closer pressure on one side of the piston. Some types of work holding use the pull to close and grip the work. Others use the push. There is no relief when open as open for a pull chuck is closed for a different type of workholding.
Your popping filter indicator means there is something amiss. Along with your having been into the closers. Plugging the hoses might be something to try.