Arc OK intermitent issues on torch fire

phillc54 wrote: Aha, so no need to worry about the transfer side yet.

Disconnect the plasma machine cnc port from the controller and short out pins 3 & 4, that should turn the torch on.

Will do tomorrow cheers.

luftlupus wrote: na no pilot arc or anything i am assuming the relay is gone at this stage. it tries to fire but no arc of course just air.

Check the plasma as Phill said in the last post, stop wasting time checking ARCOK and relays while there is no way of getting it since the plasma is not cutting anything.
If the plasma turns the air on but does not fire, that is a plasma issue, not a relay issue.

luftlupus wrote: Will do tomorrow cheers.

Tom's post reminded me to say you should check that your air pressure is within specs as well.

tommylight wrote: If the plasma turns the air on but does not fire, that is a plasma issue, not a relay issue.

Well, at least it's not a transfer-relay issue.

This is the exact problem (there's a video of it earlier in the thread) I had trying to use a SSR for "torch-on", rather than a mechanical relay. Changing relay types solved my "only air" problem.

I really hope it's his problem at this point as well, because it's easy to fix.

I read everything on this forum, so at times it is hard to follow everything exactly, but lately the "relay" issue has been raised to "nuclear" levels !
I never had issues with relays, ever, when low current is concerned as i am sure i used 3A up to 40A to turn on the plasma's, used 3A to 30A for ARCOK. Until lately most of them were old used relays. Not a single issue, ever!
SSR is a different beast, it is a semiconductor so might cause issues.
In general, if the plasma is turning on the air but there is no pilot arc or no cutting, check the air pressure as the first thing, it might have enough pressure while the valve is closed so the plasma will start, and that pressure will go down when the valve opens restricting the plasma from firing. The pressure for normal Plasma sources should be 5 to 5.5 BAR while the air is running through the nozzle, not while the air is shut off.

phillc54 wrote:

luftlupus wrote: Will do tomorrow cheers.

Tom's post reminded me to say you should check that your air pressure is within specs as well.

Your post reminded me about chasing the wrong rabbit here !