esab ultrarex retro fit plasma / flame cutter

jd896 wrote:

next what do people think would be the best way of doing the hight control i.e. turn the output of of it then pause say 3.1 seconds (how long it take torch to go all the way down) then turn the output on for power source wait for the ok signal back then start motion, and on finish cutting command turn tourch up output on for say 3 seconds to clear plate and start move to next cut

would this be in some classic lader or gcode sub routine?

thanks john

That can all be done in G code with G4Pn for the pause and M66ish (iirc, check manual) for the digital input and a similar one for digital output.

John

that would mean coding in the post file of the cam software would it not

would it be just as hard/easy to code in ladder is it possible to be done it ladder i suspect quite easy from the reading ive done but how would you call the ladder or could it even be an m code ?

i just want to get away from changing the post processor in the cam software i have less of a clue about that then this my perhaps backward view is it may be easier to make linuxcnc interpret the code of the cam in the right way rather than make the cam produce it right if it were

also as far as connecting contactors and relays to the 7i37ta ive read about this r/c snubber circuit or free-wheeling diode to suppress back emf from the relay coil what kind if any are we talking about here is there different voltage/current ranges ?

thanks john

Any way you look at it your going to have to change your post processor to add your needs. It could be as simple as calling a named subroutine (that's what I do) with the G code in it. Ladder is not really the place to execute G code.

John

Almost any diode will work as a free wheeling diode as long as its voltage and current ratings are adequate
a 1N4001 is a good choice for a 7I37. The important thing is to get the polarity correct. The diode cathode (stripe end) should go to the positive side of the coil. For small relays (say 100 mA max) the 7I37 will work without a free wheeling diode
but will generate more noise as it switches off.

Probably not the right thing to do but as a temp fix I have powered the relay off the computers psu and upon a following error erlia (estop relay) the keyboard lights flashed and no longer responded until I unplugged and reinserted it so I was wanting to choke the relay more than just the card

Having looked at the specs that would be ok for most would it not

sorry for the above wasn't thinking straight must have been tired

hi guys im trying to tune my axis only the x for now as the drives not come back from repair yet

but can anybody give me some clues as to how accurate the scale in the hal scope is ie what the u's and such relate too i want to know how close my error is

also what would people say it acceptable for a plasma gantry ?

thanks