Home Forums General Discussion Technical Questions Tac 50-04 651 Drive Fault

Hey guys, I’m having an intermittent drive issue with a Tac 50-04 I would like some guidance with. So what’s happening is, intermittently this drive will fault out with a 651 fault and won’t run until the drive is reset. The fault description reads as such:

Car fault: 651. VVVF current Regulator Hardware Error- illegal fault bit combination. Drops safety string via WDPF. Will not close safety string until given a manual reset request from the CPU or a DSP board reset. Red LED on DSP card will be on solid.

Sometimes it will run for a day, sometimes it won’t run at all before it will fault out. We have changed the current regulator board thinking that would fix the issue and it ran for about 8 hours then faulted out again, same thing. We have replaced the auxiliaries on the MC1 contactor, checked tightness on all the terminals. It’s got a VVVF regen drive 460VAC 60 HP drive installed currently. Any help would be appreciated.

On your regen card, make sure J1 & J2 jumpers are on for 60hp and R160 is in place for 460vac. This comes from a difference in the DCN parameter and actual hardware configuration. I doubt DCN is wrong but should verify. Intermittent connection between the 2407MC, Current Reg, and Regen Card could cause this so check ribbon cables. Noise could cause this too, make sure all contactors & fans have suppressors. If all that checks out I’d try the regen card next, then 2407MC. Wouldn’t rule out the power supply either and make sure it has a 20 ohm 5 watt loading resistor connected across the 5vdc output.