Maybe a THC problem?

[hbg]

Whats up guys, I have a Ez router with TD a40 plasma cutter using sheetcam/mach3. During mid cut the volts on the torch height controller & torch will climb and then lose arc when cutting 14g. Ill have it set at 105v will make a few good cuts then during mid thru a cut it will climb up to 130v on the controller causing gouge then lose arc. I then re-run back to m05 and will do it again at the same location. My table is grounded, Plasma is connected to the sheet, new consumables and clean dry air set at steady 70-75psi. So Maybe a THC issue? Any help will be appreciated.

[acourtjester]

The voltage may be changing because the torch is moving up, could you have the up/down signal crossed from the THC.
Watch the volts as it cuts it may not need correction and after some cutting it needs to correct but goes the wrong way and keeps trying to correct until it gets to high.

[Old Iron]

If it's doing it in the same spot, look for a bad connection or a broken wire.

[hbg]

well don't think it's a loose wire/connection because it doesn't do it at the same area on the table. I meant it will do it on the same spot on g-code when I re-run it. Could it be sheetcam or mach3 putting out some error on the g-code cause volts to change? As far as crossed wires on the THC how would I find that out? I bought this table used didn't mess with none of the wiring or settings.

[acourtjester]

If it work fine before and this just started then the wiring should be alright.
G-code cannot change the volts it can only set the voltage that is used for a target voltage is you have the electronics that work that way
Like CancCNC's DTHC. If you are using one like Proma there is no connection between it's set voltage and what it show during cutting.

[tcaudle]

When its starts doing that click off the THC button in MACH and watch the cutting voltson the readout of your THC box. If the volts don't stay pretty constant and start to drop then the THC is trying to raise the volts. If the THC torch goes up so will the volts. The THC box sould have UP and DOWN LEDs and show you if it is trying to raise or lower the torch. The torch needs to be moving the same direction as the UP down indicators or i will do the opposite of what it should.

I don't think that THC has communication to/from MACH for any of the settings.