Manufacturing Information Solutions

[franke]

Can anybody help me with a problem with my old Fanuc 6T "A" motherboard. The watch dog alarm comes on when I turn the machine on. Does anybody have the circuit diagram for this board or some sort of testing procedure to be able to fix this problem. This control is fitted to a Mazak M4 lathe wich has been a great machine for many many years and has only just developed this problem. Im too scared to call Fanuc as I have been severly stung by them once before.

Any help would be appreciated
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Thanks for everything.

[dawn]

Here are a couple of thoughts:

Have you checked both your parameters and your timers? I know Fanucs usually give a watch dog timer when powered up if the parameters are gone ( well this is true on turret punch's)

You need to check all your fuses and some of them are hard to find. You also need to check to see if the green ready light are on all the drives, servos and spindle controler. Sounds to me if the screen is not coming on the problem is in the power supply for the mother board. There is five fuses on mine. Also on the biger fuses you have to remove them before testing. If the ready led is on you don't need to check the fuses on them.

It turned out to be a bit of solder shorting out a couple of pins on one of the chips on the mother board. How feaky is that. I just came across it by sticking the mother board under the microscope. Just as a matter of interest I was having trouble with the spindle speed not staying constant and being very eratic. after changing quite a few components on the motherboard wich control the spindle speed and it not fixing the problem. After a lot of head scratching and frustration it turned out to be the RV03 module on the I/O board which controls the gear change. Luckily for me I have a lot of these old Fanuc parts so I just swapped it over with one out of an old 2000 control.