THC turn on in Mach3, torch fires, but no x,y or z move

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Kirkamiller
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THC turn on in Mach3, torch fires, but no x,y or z move

Post by Kirkamiller » Fri Sep 03, 2021 3:46 pm

I have a gecko 540 with Proma 150, gecko is being commanded by uc-100 smooth motion USB to parallel port interface. Only inputs from Proma are up/down, the arc ok pin is not connected to a BOB input.

I am able to cut fine with thc off. It starts off with pierce height after floating head touch off, torch turns on, after pierce delay it moves to cutting height and starts moving in x and y, at end of cut torch shuts off and retracts to safe travel height.

When I turn THC on from the Program run tab and cycle start (same gcode as before). The torch moves to the first cut start, the torch fires continuously and there is no movement in x, y or z. I have to stop the program to get the torch to stop firing.

I thought the THC was a benign thing that when working well it only nudges z axis to good effect. I didn't think it could affect the x and y movements.

I searched thru the previous posts and didn't see a symptom like that described. Does anyone have any suggestions?

As i was writing this I realized I should have checked the wiring to make sure the up/down wires are really what are connected to the gecko inputs. (I didn't wire this table, I just bought it used). Also I should futz with the test mode of the proma 150 to observe movement of the z axis.

Thanks,
Kirk

robertspark
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Re: THC turn on in Mach3, torch fires, but no x,y or z move

Post by robertspark » Fri Sep 03, 2021 4:59 pm

waiting for arc ok / transfer signal

Kirkamiller
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Re: THC turn on in Mach3, torch fires, but no x,y or z move

Post by Kirkamiller » Fri Sep 03, 2021 5:22 pm

I don't have a spare input to run arc ok. Is it possible to configure Mach 3 so that it always assumes the arc is ok?

Kirkamiller
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Re: THC turn on in Mach3, torch fires, but no x,y or z move

Post by Kirkamiller » Sat Sep 04, 2021 1:46 pm

I think I figured it out. If you aren't running an input pin to receive the "arc ok" and you want to run the THC, then it is done thru the "ports and pins" engine configuration in the "mill options" tab by checking the "allow THC up/down control even if not in THC Mode"

weldguy
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Re: THC turn on in Mach3, torch fires, but no x,y or z move

Post by weldguy » Tue Sep 07, 2021 10:36 am

Thanks for posting your solution, could be very helpful :Like

adbuch
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Re: THC turn on in Mach3, torch fires, but no x,y or z move

Post by adbuch » Wed Sep 08, 2021 1:44 am

Kirkamiller wrote:
Sat Sep 04, 2021 1:46 pm
I think I figured it out. If you aren't running an input pin to receive the "arc ok" and you want to run the THC, then it is done thru the "ports and pins" engine configuration in the "mill options" tab by checking the "allow THC up/down control even if not in THC Mode"
Thanks! That is great information to have for future reference. I use Mach3 for one of my cnc routers, but not for plasma - but still good to know.
David

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