Denford Software & Machines

Hi all. Hope someone can help me with my problems. I have just obtained an old Triac ATC Fanuc OM mill (1990'ish) and have a few problems with it. When I try and run the machine, I get an alarm message saying ***1000*** Zero Machine, and then nothing else happens. I have tried what I think is the correct procedure for zeroing, ie start up with the 'P' and 'CAN' buttons pressed and then homing. The homing doesn't seem to be working though. The 'Y' and 'Z' axis seem to home OK, but when I press the 'X+' button, the table moves faster than the othe 2 axis for about 1/2 second then stops without homing. If I press it again, it just moves a bit more, but still does not home. I have tested the limit switches, and they seem OK. Are there separate microswitches for limit and homing ? I can jog all 3 axis upto the limit switches without any problems, so i know there are no obstructions. Any advise is welcome.

Are there separate microswitches for limit and homing

The usual scenario on Fanucs is 2 switches per axis, one for homing and one in the Emergency stop line for extreme overtravel. Its possible to have + and - limit switches as well, but I doubt we'd have gone to that expense, but I could be wrong. Software travel limits in parameters are then active once you've homed out (and beforehand as well I believe, unless you've powered up with PQ and CANCEL)

I'd go to the input diagnostics and see if you can active the home inputs and seem them change on screen - X16.5 according to the manual here

Have you tried both the X buttons when trying to home? It may be either X+ or X-.

yes, tried both x+ and x-. Any idea how to get to the homing and limit switches ?

The X axis datum/limit switches are mounted on a aluminium plate behind the back of the Y axis front bellow/cover. There is sometimes a long cover fastened to the front of the table that needs removing first. You then can remove the back screws holding the front Y bellow in place. The Z shaped plate with the switches on is also fastened on with the same screws. You should be able to at this point drop the whole bracket off with the switches on.

The X axis limits switches would show up as a E-Stop if either were pressed or faulty.
The X axis datum switch should show up on one of the diagnostics on the firs or second page. From what I remember they are someting like , 15 bit 4 =X
16 bit 4 = Y
17 bit 4 = Z

You should be able to work it out easily by moving over either the Y or Z datum switches.
It still sounds from what you are saying that it may just be as simple as the X axis button being pressed. Does the light on the X buttons operate the same as on the Y & Z during homing?

Are there any alarms at this point?
Is there air to the machine?
Can you jog the X axis both right & left?

ALl sorted, it was a combination of me pressing the wrong button, and i've also noticed that if the bed is too close to the limits when you home, you get a table limit error before it homes. Just need to work out how to input a program now. Thanks for all the help.

I was told that the axes need to be at least 50mm away from the datum switches before you try to home or you get the errors

yes, that sounds about right. lots to remember when setting this machine up.

I seem to think it's to do with the axis must get up to speed 1st before hitting the switch - otherwise you may get a different home position as the axis would stop/reverse on the switch quicker