XA axis servo trouble

[MetaKnight48]

I'm working with a MultiCam Pro Series CNC router in our college lab in North Carolina and the XA axis servo keeps shutting off during motion. We swapped motors and confirmed the 4-pin cable is good but the issue stayed on the XB side. The 17-pin cannon plug looks fine but I don't know what values to check for continuity or signal. Is there a way to test the plug without pulling the whole harness? We're trying to get the machine back online before next week's student projects are due.

 

[the nonchalant guy]

You've already done the right thing by isolating the problem to a specific area which is half the battle. For the 17-pin cannon plug, you can test it without taking out the whole wiring harness. You'll need a good multimeter and a wiring diagram for the machine's control system. Use the multimeter in continuity mode to check each pin to its corresponding connection point at the other end. If you have a specific resistance value from the manufacturer, use the ohm setting. You're looking for any breaks in the circuit or a reading that's way out of spec. It's a bit like checking a car's ECU harness for a bad pin or a broken wire; it's a slow and careful process but it's the only way to be sure before you start replacing expensive components.

 

[Kwanda_Rosman]

If the fault stays with the axis after swapping motors, your problem isn't the motor... it's the drive, harness, or control side. Cannon plug might "look fine," but that means nothing. You'll need to meter every pin, no shortcuts. If you're under time pressure, start budgeting for a replacement harness or drive card.

 

[MetaKnight48]

Thanks for both replies. You're right that the motor swap ruled out the hardware side, and the issue staying on the XB axis points us toward the harness or control. We've got a Fluke meter and access to the machine's wiring diagram, so we'll start testing continuity and resistance across the cannon plug this afternoon. I'll log each pin's reading and compare it to the expected values, though I haven't found a spec sheet that lists exact tolerances yet. Do either of you know if MultiCam publishes those values or if we should go by general servo signal ranges?

Given the timeline, we aim to complete diagnostics by Monday and either repair or replace the harness by midweek. If the readings are clean but the issue persists, we'll shift focus to the drive card. I'll post an update once we get through the pin tests.