Problems running the THC troubleshoot

How does the first step in the THC VOLTAGE CHECK GUIDE (https://cdn.shopify.com/s/files/1/2587/7650/files/THC_TROUBLESHOOTING_FLOW_CHART_REV._B.pdf?v=1623856869) work.
I want to verify that my plasma cutter’s 50:1 voltage divider port is functioning properly while cutting. So I have to run a straight cut and put off the THC.

But how can I make that cut if I have to take of the cpc port cable? As soon as I unplug this cable I cant fire my torch. So I measure 0.0 Volt at my cpc port.
Am I missing something or am I just being stupid?

Crossfire Pro with Hypertherm 45XP with cpc port and I bougt the cable from Langmuir to connect the cpc port.

You can take that reading from the divided voltage cable that plugs into the DIV input on the VIM box. Put one probe on the inside of the plug at the end of the cable and one probe on the outside.

What type of issues are you having with the THC? It is not very likely that the Hypertherm divided voltage output is to blame.

Well, started a topic on ‘losing the ARC’ a while back (Can't cut new drawings. Error: Torch starts moving before cutting voltage was sensed. UPDATE! - #7 by Joep).

In the end they sent me a new VIM box, but that didn’t solve the problem either. I kindda gave up for a while, but now I bought the hypertherm xp45 with cpc port and hoped this would be the end of my problems.

But again I get lots of ‘lost Arc’ failures during cuts. It’s driving me crazy, so I thought to start over from the beginning and start by going through the THC troubleshoot just to clear things out.

Sometimes it cuts really great, but I can rarely finish a piece without the ‘retry’ button and ‘cut from line…’. Most of the time it gives the ‘Lost arc’ notification check clamp, cut height or pierce height is to high or to close to other cuts. But the clamp is on the workpiece, cut and pierce height is correct (1.5 and 3.5 mm as written in the hypertherm manual).

So it seems that even with the new plasma cutter I am running against the same problem…

It may be your piece delay. The first pierce matches book specs for hypertherm, but the subsequent pierces have a longer delay do to post flow. Hypertherm measures pierce for start of are. Fire control measures from signal. So there is a lag from signal to actual arc due to the post flow. On the 25’ machine touch I add .4 the the book pierce delay . On the hypertherm 45xp

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