Wierd G31 system error - ideas?

[la_coterie]

I've been making a centering probing macro that the probe is somewhere near the center of the hole and moves +X -X +Y -Y and sorts out a G54 for me.

The problem comes when X goes the minus direction, it's ok if it doesn't actually probe, ie, make contact but if it makes contact I get system alarm 930 - CPU error - sounds expensive! :frown:

Y axis is fine no problem and the machine works ok otherwise.

Has anybody come across this and discovered what to thump? (impact maintenance, a wonderful thing )

I've not done any macros on the machine before..

[cncdiag]

Sound like a shorted wire to the X- switch.
When the switch makes, it pulls the power supply down.
What control is this?

[la_coterie]

It's a OM-C about 1992

Surely it can't be a short as it's the same switch for each probing action (actually at the moment it's actually only a micro switch "plumbed" into the cabinet)

I've not checked it out but my thoughts were that it was freaking while taking into account backlash - Cos I note the number it stores it a smidge off the actual reading but I've not had time to check out the backlash params (I've got them marked somewhere..)

[Al_The_Man]

Is this the regular skip input or do you have high speed skip?
To test it I would command a G31 at very slow feed and trip it manually in the problem axis to see if it alarms.
Depending what skip input you have it is a 24v or a 5v input, but both generally take the input down to signal common.
Al.

[la_coterie]

Just a regular skip input, 24v.

In effect I am tripping it manually as I don't want to sh*g a probe while testing out the code. It's just a couple of wires attached to a microswitch that I press to immitate contact at the moment - of course going back to the relevant terminals in the control.

It works in 3 directions why should it freak out doing -X ?

I've got feed set at 100mm/min at the mo, I'll try something slower tomorrow & report back...

[la_coterie]

Tried setting the feed down to 10mm/min still trips

Tried removing the backlash in the params still freaks

I'm reading the param book to see if there's anything in there. Cor! thats for insomniacs!

Any ideas?

[Al_The_Man]

In my manuals it implies that this alarm will occur when an external interupt occurs it cannot process may be due to defective interupt CPU or memory process on the board, maybe there is a seperate interupt routine for the different axis directions?
Al.