View Full Version : overcurrent alarm on em806 driver

30-03-2017, 09:41 PM
hi all. just wired up my em806 drivers and steppers today. two drivers are fine running 3Nm nema 23 motors but my x axis drive which has a 8.5Nm nema 34 has an overcurrent alarm on it (red light blinking once every 3 seconds) I am not sure how to get rid of this. The manual says:
"Over-current protection will be activated when continuous current exceeds the limit or in case of short circuit between motor coils or between motor coil and ground, and RED LED will blink once within each periodic time."
if I disconnect the motor the alarm goes away but reconnect it and the warning is back. I have checked all my connections and none are shorting but not sure what else I have to check, please help

31-03-2017, 12:29 AM
You have checked the motor is wired correctly?

Disconnect the motor wiring at the EM806, and using a multimeter, check for continuity between the wires you have connected to A+ & A-, B+ & B- (both readings should be very similar), then check there is no continuity between any of the A & B terminals, and also between A & Gnd, and B & Gnd.

If both A & B coil resistances are not similar, test again directly at the motor wiring.
Or if you have continuity where you should not have continuity, then you need to work out where the short is, at which point I would start by disconnecting the motor wires one at a time and checking continuity each time. Ideally keep the multimeter connected, in case you disturb the short while disconnecting something else, so you'll know what you last moved when the short cleared.

31-03-2017, 11:01 AM
yeah checked all continuity, all read the same and no shorts to the motor body. swapped connections to another driver and it works fine on there. Spoke to zap this morning and am sending that one driver back. Thanks for the help