Voltage on G540 phases

[Sandy H.]

Just learning a bit about this CNC stuff and am starting up a Gecko G540 based system. The motors make noise when just sitting there, so I measured a few things. I'm not sure if the noise is normal or not, just investigating.

The PS output voltage is 48.2 VDC with an AC component of .004 VAC. I measured the phase voltages on the output of the drive at the motor and got 2.5 VDC and 22.5 VAC. This is occurring without the parallel port hooked up, just the PS, G540 (charge pump off) and one stepper. I did install a current limiting resistor. Also, when hooked up to the PC, the motor responds as I think it should and the noise goes away when running and takes a short moment to come back when it stops. Volume wise, it is about as loud as a fluorescent light starting up and is much higher in pitch, kind of a squeal instead of a hum.

Just trying to figure out if this is normal or if I should pursue the recommendation of adding a filter cap at the input of the G540.

Thanks for any thoughts.

Sandy.

[keebler303]

have you adjusted the trimpot on each drive? It will help tremendously with smoothing out the motors and reducing noise. Its covered in the manual. Other than that, you will have a little noise but it shouldn't be too bad. Also make sure you aren't sitting your motor on a table or something that is acting as a sound board and amplifying the noise. If you are, it will be much quieter once its bolted on to something solid.

Matt

[Sandy H.]

BUSTED!!!

My wife was out of town and it was cold in the garage, so I was bench testing on the hand made solid oak table in the living room. My goal was to fully start this thing up electrically before attaching it to the machine so I was confident that I had directions, E-stop rough RPM etc set correctly to hopefully eliminate and surprises. I bet the table is 100% of the issue.

As far a trimming the drive, while having 'go-fever' I opted for the "if you don't have an insulated screwdriver, be extremely careful not to touch anything when adjusting the trimpots" version instead of the "use an insulated screwdriver to adjust trimpots" method in the manual. As I was doing so, I was even thinking to myself "at least wrap the screwdriver in electrical tape" then 'POP!' and 'OOPS. . . '

It was making the noise before that and it seemed the same on the remaining 3 channels, so I don't think any real damage was done. I pulled it apart last night and see the problem, but I'm not an SMD repair guy. I'll send it back to Gecko for evaluation and pay to have it fixed if it is practical. For now, 3-axis is all I need anyway.

Thanks for the confirmation. I bet everything is right on track for when it is attached to the router, hopefully this weekend.

Sandy.

[keebler303]

Sandy, you can remove only the affected drive to return and continue to use the G540 with the remaining 3 axes. I'm pretty sure gecko needs to start supplying nylon screwdrivers with their drives.

Matt