thc off and on problem

[matin]

.
I have candcnc controller and pwm sensor and mach3 software.

When I use code M 101 to turn off the thc again after 1 or 2 cut my z axis will move.

I want to turn it off safely and when I need turn it on . How can I do it?


2) Is this normal : when plasma is off and arc ok signal is off and thc on and any codes not running , I test thc up and thc down signal as emulated checked in mach3 and with u key torch goes up and with d keys torch goes down .
(in mach3 allow thc up/down control even if not in thc mode already checked)

Is it normal ? I worried in this case when the thc mode is off ,we still have z movements ,when mach receive the signals up and down from thc card.

3) the important part of my question : As I wanted to cut small holes
I used code M101 before first M03 code in my program to turn off thc mode , and then I ran the program , it cut first hole without problem but in the end of second hole cutting , torch suddenly dived down and hit to the sheet. I never thought ,this happened , because I Used code M101 to turn off the thc .How it is possible? Auto ht is off but in mach3 allow thc up/down control even if not in thc mode is checked .




Could you please help me ,What was the problem ?

Please help me .

[I Lean]

Not positive on the "allow thc moves if not in thc mode", but that sounds like it should NOT be checked. One thing to check for sure is the box that says "auto thc on", or something to that effect. It will automatically enable the thc for you, so make sure that one is unchecked.

[beefy]

Hi Matin,

The tick box for "allow thc up/down control even if not in thc mode" is normally off for plasma cutting. It should not have been on in a standard Candcnc install so I'm guessing you turned it on.

I think it's main purpose is for when you want to manually adjust z height. This is common when oxy acetylene cutting and THC will be off, but you want to adjust the z height manually. So the tick box description could be described as "allow manual z adjustment when THC is switched off". I often find a lot of these technical "descriptions" for tick boxes do not really describe the purpose very well. Somebody had to tell me what it meant, I didn't have a clue.

By the way the best help for Candcnc products is the Candcnc Yahoo Group. That's where Tom and Luke (from Candcnc) answer lots of questions, plus it's where a great many Candcnc users "hang out".

Plus Mach is at the core of the Candcnc products so the Machsupport site also has a support section where you can find a lot of Mach users. Even though they might not use Candcnc at all, you can learn lots about Mach itself.

Keith.