One M50 is broken, can I copy it?

[John3]

Hello,

My Tsugami Lathe has two spindle/turret sets. They are controlled by a dual FANUC 0T-B controller(two seperate controllers, one monitor/keyboard and a switch to switch between them).

M50 is a oneshot command that allows indexing of a turret with total disregard to where things are at (dangerous but very useful). The command is put after any Txxxx address to allow turret indexing anywhere/anytime.

On the Back Spindle controller this command works fine. On the Main Spindle it doesn't work. It can be executed but does not have the desired effect of overriding the index safety lockouts.

I'm in an area I know next to nothing about, probably this is some sort of ladder function?

I have some scant Japenglish documentation for the ladder logic but know only a little on how to read it and absolutely nothing about entering ladder logic diagrams in a fanuc control.

Is there some way that I can use the working example of the rear turret M50 to get the Main spindle one working.

John

[Al_The_Man]

Originally Posted by John3 On the Back Spindle controller this command works fine. On the Main Spindle it doesn't work. It can be executed but does not have the desired effect of overriding the index safety lockouts. I'm in an area I know next to nothing about, probably this is some sort of ladder function? Is there some way that I can use the working example of the rear turret M50 to get the Main spindle one working. John

Your right, the M codes are decifered in the ladder,
Modifying the ladder requires a fair amount of resources, both in hardware & software.
If there is a Fanuc retro-fitter in your area, he should be able to make the M50 the same on both sides.
Strange they made them different originally, maybe an oversight.
Al.

[John3]

Originally Posted by Al_The_Man Modifying the ladder requires a fair amount of resources, both in hardware & software.

Al,

Thanks, for the reply.

If I haven't completely killed the controller (see previous post) I'd like to get the M50 working.

I'm an electrical engineer with extensive hardware and software experience, just not with Fanuc controls. Would you give me a basic ides of what is needed to view and modify the ladder logic?

Originally Posted by Al_The_Man ...Strange they made them different originally, maybe an oversight.

It may not have been the machine builders. this machine has been around the block more than once. Maybe something happened to it in the field?

John

[Al_The_Man]

If you cannot view the ladder right now in the diagnostic screen then you should check if P0060 bit #2 is set to 1.
There are some different versions of ladder memory.
If you have a yellow cassette sticking out from one of the MB cards, this will be the ladder eproms, the control loads the ladder at power up time from the cassette and then runs it.
Usually you can remove this cassette after power up and as long as you do not power down, the ladder is in ram.
These eproms are programmed off line in a ladder development SW and Fanuc programmer or PC software & cassette interface.
You would also need a Fanuc PMC manual for the description of the various PMC elements and techniques.
When studying the ladder, it helps if you have prior experience with PLC Logic & programming.
Al.

[John3]

Thanks again Al,

Very interesting, thanks for the info!

I had no idea the PMC data was in eproms. I thought it was programmed via the PMC parameters. What are those parameters for?

On this machine I've now got a sequence error light on always. If possible, please see my recent post about this. I hoping you have some words of wisdom for me.

Thanks,

John

[John3]

Originally Posted by Al_The_Man If you cannot view the ladder right now in the diagnostic screen then you should check if P0060 bit #2 is set to 1.

Al,

P0060 Bit #2 was 0, I set it to high. I don't see a change, what should I be looking for on the diagnostic screen.

John

PS: Any suggestion about my Sequence Error Light?