Same problem as others...no solution. No THC live voltage

I just finished assembly on Monday and part of Tuesday. It actually felt satisfying although I still cannot tighten the lead screw nuts or the thing gets stuck. It is perfectly square and the stepper motor mounts are perfectly horizontal…I closely check these items at least five times during assembly.

BUT, after almost three days of troubleshooting until 4AM I am getting beyond frustrated. I have carefully read the many posts about no live voltage and have checked and re-checked everything that I see mentioned - including torch fire wire continuity (OK), torch fire port continuity (OK), no ground issues (took electronics box off frame), relay properly installed (OK), THC chip properly installed (OK), only the Langmuir item plugged into outlet (done),I used raw voltage cables properly tapped (no impact) and then switched polarity (no impact), also have DIV wires to pins 5&6 of Hypertherm and tried using this connection rather than raw voltage (no impact), installed and re-installed driver (no impact), installed and re-installed Firecontrol (no impact).

The torch will fire by using manual option. When I run a simulation the torch moves as it should. When I try to cut for real I get the torch on for a second giving me a pierced hole and then a shutdown saying no live voltage.

I have run the THC test program 20 times always with the same “no live voltage” results.

Is my VIM bad?? Why do I have no live voltage if all these other things seem to check out? The fun is fading fast here…please help!

Where is the wire that goes from the VIM to the control box connected? For raw, it should go from the PV out to the control box. For divided, it should go from the DIV out to the control box.

Yes, both alternatives were tested many times. Raw voltage with THC cable to PV out on VIM and then (separately and alternatively) the DIV input with the THC cable to DIV output on VIM. I’ve yet to discover a scenario that gives me live voltage.

And to confirm…the red wire (inside of plug) has been confirmed that it is connected to pin #5, and the black wire (outside of plug) is connected to pin #6 as per the VIM Box Wiring Schematics guide for Hypertherm.

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Another very weird event is that the torch will not manually fire some times. If I pull the “torch on” plug and short the cable, the torch will fire. Then if I re-plug it in, all of a sudden the manual fire now works. Something is definitely wrong here…what might be the cause?

It could be a bad VIM. Have you contacted Langmuir through the support email? Another variable not covered yet is the torch. Are you using a machine torch? The Hypertherm CPC cable will not work with a hand torch.

Do you have a multimeter to test actual voltages? It seems like you’ve tried common solutions but haven’t yet nailed down the actual problem.

The THC Voltage Check Guide starting on page 2 is likely what you are looking for. This will determine where the issue lies.

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I have been through the troubleshooting flow chart. Here are some more fun facts:

  1. Although I wired exactly as told to do according to the THC instructions for Hypertherm, red to pin 5 (which should be the inside of the barrel plug) and black to pin 6 (which should be the outside of the barrel plug), the test voltage came out reversed and I had to switch the wiring. Is the red NOT the inside of the barrel plug?? Anyhow, this is now giving a positive reading for VIM input from the 45XP.

  2. I now get VIM input voltage of 2.72v and VIM output voltage of 2.02 volts which seems about right according to the troubleshooting guide.

  3. I was actually seeing a live reading of 9.4v in the THC control panel, but when I re-connected the THC lead from the VIM, it is now back to zero. Running the THC test (where things fire as they should) is back to producing a result of zero.

  4. the ohms between the slat and the USB port are 1837.

Yes…machine torch.

When I try to cut the test bottle opener in dry run, it seems fine. When I try a real cut I get a one second torch and then nothing. Here is the program attached.
1001.nc (1.8 KB)

Also…the measurement from point A1 to Ground on the module was 4v.

Just did the THC test again (right after testing the THC cable) and I get zero live voltage results and the message that I must not be getting any voltage from the THC cable. Makes no sense as the cable when unconnected to the electronics the cable seems to put out what is needed. After connected, there seems to be failure.

What type of voltage number should I see in the Live red box under THC. I though that somewhere that was upwards of 115v.

live voltage is only read when the cutter is cutting something. i think first you need to figure out the torch firing issue. have you tried turning off thc and ihs and tried to cut something?

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Any luck with this issue ?? I’m having same exact issues to the t ! I’ve got 2 Volts from vim while cutting but when I plug in to thc port the live goes to 0. I tested the port with a battery and it is registering voltage in the live … what am I missing??

Welcome.

Maybe you could enlighten the situation with some of your particular details.

What kind of plasma torch do you have?

Are you using raw or divided voltage?

Are you using a factory connection to your plasma torch or are you doing a field spice?

Does your table operate correctly without using torch height control?

If your this far along it doesn’t sound like you’re too far away from cutting some parts. I’m sure someone on here can get you going.

Make sure that you are running your laptop on battery. If using a desktop pc, you’ll need either a UPS or to connect the power cord of your pc and monitor with 3-2 prong adapters.

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