I need help with a problem with my SX3. When I turn the power on to the mill the green power indicator light comes on, the spindle speed LCD display blue back light comes on, but there is no indication on the display. I mean nothing on the display.

Also, if I try to start the spindle motor by hitting the start button, nothing happens. It is as if the machine is dead.

The model number on the motor controller is: FC1000WJYA(6.2) with a manufacture date of 2006.07.25.

Things I have checked are:
1) 20 amp fuse on AC power line is good.
2) 20 amp fuse on motor controller is good.
3) checked for loose connections and everything is tight.
4) looked for burn spots or burned up components on the PCB and none were found.
5) 8 wire connector at the bottom of the board has the following voltage readings relaive to ground.

S1 K3 K4 +5V GND SA SB SC
83Vdc 80Vdc 80Vdc 6Vdc 0Vdc 0Vdc 6Vdc 0Vdc

Kind of odd to see 6 Vdc on a connection labeled +5V but I traced it down to an LM7806 (6 volt regulator) and the PCB is stenciled 7806 next to the part. Go figure.

6) The connector on the right hand side of the PCB where the 120 Vac comes in has the following readings relative to ground.

L1 N1 FG U V W
125Vac 0Vac 0Vac 14.8Vac 14.8 Vac 14.8Vac

7) Checked the wiring harness for continuity from motor controller to push button PCB located on the front of the machine. Wiring harness checked out with no shorts.

8) Checked the tapping button electrical switch for shorts or grounds. None found.

I would appreciate any help in getting the mill back up and running.

Not sure if it applies to the SX3 but when faced with a similar situation with my X3 being 'dead' I have usually forgotten two things

1) The speed pot wasn't at zero before starting
2) The spindle guard wasn't closed

Alternatively as it's an SX3 you could just have a knackered controller - pretty common unfortunately. Without detailed schematics it's an almost impossible job to diagnose.

M100,

I have a call into Grizzly for tech support. The person on the phone admitted that he was not an expert on the SX3 and that he would have one of their electrical experts give me a call within 24 hours.

I'm still waiting for the call.

Did you check the emergency stop button?

I had a similar problem with mine after I bought it. It ran for a few days and the controller board went out. They replaced it and it has been fine ever since.

Yep, checked the emergency switch and it isn't the culprit. I can even hear the relay energize / de-energize when I push the emergency switch or the chip gaurd switch.

on the sx3 there is a problem in the z axis dro that shorts the motor if i mind right
been mentioned on here before
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