Hello Engineers and Machinists, I have a few problems with a Colchester Triumph Electronic CNC lathe, fitted with a Fanuc 20 T control. I bought the machine a week ago and powered it up for the first time and discovered it has a few problems.
When first switched on it threw up faults on both axis, the spindle however seemed to work as is should, the 3 buttons on the apron panel (stop, forward and reverse) worked as they should and the spindle ran up to speed as it should. The z and X axis refuse to move but the servo drive shows no errors. At this point I thought that it could be that I had wired the transformer for the machine with the 3 phases out of order so I changed the phases and now the errors on both axis have disappeared. I can now move the and home both axis. The problem now is that the spindle refuses to spin either in forward or reverse, the 3 buttons on the apron panel do not illuminate as they are pressed and the motor does not start. The gear change buttons on the operators panel that also change the gearbox from low to middle to high gear range also do not work.
The spindle amplifier is showing a steady "--" which I believe is as it should be and there are no spindle error messages on the Fanuc Control, but the spindle refuses to move.
It seems to me as if the spindle drive is waiting for a signal to "Get going" but something somewhere is not working.
I have checked the following:
All the plugs and wiring in almost the whole machine
The chuck guard switch is working and in the correct position
The voltages to the power amplifier, spindle drive and servo drive are all within limits
All the fuses i can find have been checked and are good
All the breakers are good
The spindle parameters are as they should be.
What I have noticed is that I have only 5 volts going to the RPM potentiometer on the apron panel, should this be 10 volts?
I have only 7 volts going to the forward, reverse and stop switches on the apron panel, should this be 24 volts?
I have spent 5 days tracing wires and checking voltages but I have now run out ideas, has anybody had a similar problem?
It seems strange that the spindle worked perfectly initially but now refuses to start and the only change I have made is to change the 3 phases, I have tried to moving the phases to how they where at the beginning but this makes no difference to the spindle and also causes a 401 error in the servos.