[djmcdaris]

I have a B needs ZRN alarm 300 and I have tried changing the 1815 and 1814 bits as described in fanuc book to no avail. This is on Mori Seiki MH50 with a 16 control. We did have a major power outage and the machine was not powered down so it single phased. the contacts on spindle drive burn out as well as some relays. All pretty much on 100v system.

when i do a zero return the B axis just continually rotates. Any help.

[MysticMonkey]

First Ascertain if the B-Axis has an absolute encoder

check Parameter 1815#5
1=absolute
0=incremental
P1815#4 shows when axis is referenced

If it is an incremental encoder the axis will continue to turn untill it sees the home position switch (deceleration dog) then continue untill it sees the encoder reference marker

If it is an absolute encoder I would expect it to alarm

does the B-Axis 'count up' or 'roll over' ?

Parameter 1005#0 controls whether the CNC asks you to reference the axis before movement

[djmcdaris]

the axis does roll over, the B axis has a decel switch but it does not read on the diagnostics. I can jumper the decel switch and it does show an input and goes to decel. so I am wondering if the switch might be bad or I/O board. 1815 is a 1.

[stevo1]

If you jumper the switch and it goes to decel will it home the axis or just keep rotating? Do you get a something like a PS200 alarm?

If your machine homes with the switch jumpered then you have a bad switch. If it does not home you should put a scope on the encoder to see if the machine sees the marker.

Stevo

[fanucman]

I have a B needs ZRN alarm 300 and I have tried changing the 1815 and 1814 bits as described in fanuc book to no avail. This is on Mori Seiki MH50 with a 16 control. We did have a major power outage and the machine was not powered down so it single phased. the contacts on spindle drive burn out as well as some relays. All pretty much on 100v system.

when i do a zero return the B axis just continually rotates. Any help.

just do it the easy way.. call mori and ask the for a procedure..

[CNCZILLA]

Not sure why your procedure is telling you to manipulate the 1814 parameter as this is not reference position. First as stated by someone else you do need to determine if you have a ref dog or encoder. Obviously if you can jump out the switch you have a dog. If your 1815 bit 4 is set to a one and you did not change this then you have not lost ref position, you probably have a bad switch. If you changed this parameter from a 0 to 1 then maybe you didnt do the procedure correctly. If the parameter was a 0 then you would move the axis manually to ref pos and then chenge the 1815 bit 4 to a 1, then you must cycle the power, if you did not do this then this could be where your problem is. I would think your procedure would state this. This is all you do to establish reference with Fanuc but maybe your machine has something funky or in particular that is different. In that case i would consult Mori or Fanuc. Hope this helps some.

[stevo1]

Using parameter 1815.4 is only if you have absolute encoders. It was always my understanding that if you have absolute encoders there is no need to reference the machine so there would be no need for a decel switch. Since he has a decel switch I would ass u me that he has incremental encoders and the procedure for setting reference position is not used with 1815.4. This should all be done with the decel switch then once that is tripped the axis slows down and searches for the marker. Once reached it is referenced.

If the switch is not being made then it will not look for the marker. Which means a bad switch. If the switch is made and the machine does not reference then it is probably the encoder, cable, or amlifier etc.

Please correct me if I am wrong.

Stevo