Axis Hardware Failure?

[Tom Rathbun]

I am using a new Umac the rack is relatively full. 3 Digital I/O cards, 2 4axis analog cards, an analog I/O card and a serial absolute encoder card. After the machine has been on for some time, 10+ hours, suddenly the z axis faults under following error. The machine is sitting static. Z is holding position as a Non-counter balanced Z axis.

 

So Z starts to fall and the machine trips out. The only Error is Z axis following Error. The axis Drive is an allen bradley Ultra 3000 drive running in analog torque mode. The amplifier shows no error.

Using Allen Bradly software and running a trace on the drive, it shows the analog torque command signal dropping to zero. It certainly looks like the DAC output just dropped to zero for no reason. It was quite warm in the panel the aluminum UMAC rack is about 130-140 F .

 

If I restart everything comes back but the next failure happens quit quickly.

 

has there been any problems with the 4axis cards not working correctly?

[Richard Naddaf]

130-140 F (55 - 60 C) at the aluminum chassis is too hot for the electronics

[Tom Rathbun]

The specification for the Umac is 130F I assume that is ambient in the panel. My panel ambient is about 85F. i Just put a thermocouple on the rack and measured about 130F. The panel doors are open so air flow is reasonable. I have a cooler that comes on at 90F and it is NOT on.

[Richard Naddaf]

All right. In order to exclude any issues with the closed loop control, I would output a certain voltage in open loop (#nOut10), and run the test again. If do not have any logic that tells it to kill, then it should stay on "forever".