I have gotten a lot dialed in on small parts, 1/8 and 1/4" aluminum and A36 steel. Now getting ready to run larger parts and need to avoid losing material. If your cut starts on a hole, for example .5" hole and the cut starts in the center of the hole as lead in, if you have a problem then you can’t just start over as you can’t run a hole again as the nozzle just goes down inside it. I have been having repeated stalls after the first cut, with error message about the THC. I believe it may be bad connections on the divider plastic box, as I plug the plugs a bunch of times and get past the error. I observed the repeated error today, it will cut the first hole then stall on the second. The first hole shows about 127V and the second jumps to 300 where it stalls. Often I move to a new position to start over. No big deal on a small part. On a large 1/4" plate it will be a big hassle to lose a chunk of material and move over. What can I do to reduce waste on these stalls? I notice the option to generate gcode at the stall point so maybe this will one option. Other than that I can just go to sheetcam and remove the parts already cut and then pick up where I left off. Considering how many of these THC errors I am getting, I feel I need a plan to do large parts as these errors are an expected daily part of life. Any tips?
Razor weld cut 45. Changed nozzles and no effect on the error.
Run the THC health test is where I would start on troubleshooting and go through the THC flowchart.
On a restart to keep from waisting material you can use a thin piece of sacrificial metal over the hole then pull it way when you get into the desired material.
OK thats a nice trick to put a piece of metal over the hole!
Health check is within acceptable range. Floats around upper 120. Nominal shows in low 120’s.
I get the error 1 in about every 3 runs. Sometimes just run the same part in the same position again and it goes assuming the nozzle can still touch something on the first hole.
When watching the voltage, it is moving up and down in the 120 range. I will check again and watch the Z axis values. The problem usually occurs after cutting the first hole, then moves the next hole(small holes like .25") then it touches the surface, stops, shows 300, gives error.
If you’ve already cut part of your file and it stops due to an error, it will give you the option to retry the cut. That will generate a new code to move forward from where you left off.
If the fault is because the slug dropped out and caused the torch to shut off, it will try to restart from that hole. In that case, click on the next part to be cut and select “run from loop”. It will generate a new program that starts from that point.
Your typical THC popup screen. It gives some basic explanations and causes of the problem and says if you keep getting 300V to call langmuir you may have a bad board. But mine is random. If you unplug your voltage divider box, try to cut, you get this error. Usually I can cut the first hole. But not the second. It is usually not something much later in the cut, usually it is the second hole after a successful first hole. I have seen it stop later in the cut on a rare occasion.
12.8CFM, through multiple driers and oil removers, harbor freight air dryer. Compressor kicks on at 100 and off at 150 I think. Guage always floats at 75, I never touched the internal reg. I’ll try turning off THC and see.
Why does it jump to 300V on the fail? It shows 300 for a second then after the error message it goes to 0. I wonder if this is the bad board that is mentioned in the error.
Torch cuts the first hole fine. Moves to next hole. Moves down to touch metal. Torch does not turn on for the second hole nor does any air come out. Error message THC.
Exactly. If the torch does not turn on, how is it showing 300V for a brief second and the torch is not on. When the torch cuts normal it is 129V. I am waiting on reply from them. Even if the div board is unplugged or bad connection, you should not get 300V on a lost connection.
True. But FireControl has connected the problem to THC with the error it is giving. Isn’t it?
That is why I really want to see a screenshot of the error message to be sure of exactly what it is saying IS the problem and possible remedies. The fact that it is telling OP to contact Langmuir about the 300V at the THC is something different than the torch not firing.
If it was a lack of the torch firing I would expect the error “Torch moved before voltage sensed.” (or whatever the phrase is).
@tchap You still haven’t answered Richards question/thought:
THC has nothing to do with torch on /off, if it did then why do a torch still fire when Thc is disabled on a table. If his torch is cutting first hole but doesn’t cut second hole and no air coming from torch as he states, then either his pierce delay is too short, or torch on/off wire is making intermittent connection? don’t know at this point because he has not posted settings. Could be IHS switch problem or torch mounted too high in holder?
Toady now I cannot recreate the error. I pulled the THC board and plugged it in a few times. Also I don’t trust the divider box connectors at all, very cheap connectors. I will change them out soon. I can create the same error message by unplugging the divider box and trying to cut. However, with this method of simulating the same error message, the torch DOES fire THEN it throws the error. The error I have been getting since I got the machine on a regular basis is the SAME screen as you see here, but the torch does not fire before the error.
Here is what happens on the error:
Start a cut that usually is a bunch of holes first
First hole cuts fine.
Move to next hole
Lower nozzle to touch surface, does not fire torch.
Error then pops up. Shows 300V for a second then goes to 0.
My default Pierce delay is .6. Pierce height, .1181. Cut height .0591. All defaults in SC
