Centroid Community CNC Support Forum

Here is another option: https://centroidcncforum.com/viewtopic.php?p=62875#p62875 I bought a 2.6 kw one for a mill spindle motor and it works great. They make smaller ones as well. The 2.6 Kw motor and driver was $357.00 plus shipping. I can get the JMC contact info to place an order if you would li...

I solved the fluctuating voltage problem by connecting the servo driver enclosure and main enclosure with a common ground wire! One question... The analog out signal measures. .05 volts when I turn the spindle to 0 rpm. Is this acceptable or should it read 0? I did run the spindle bench calibration ...

Thanks. I will check that out

I connected the two enclosures with a 10-gauge wire to have a common ground, and 90% of the voltage fluctuations are gone. I'm going to do a bit more testing, but I think I am pretty much there.

Hello Tom, I performed your suggested battery test by removing the leads from the Acorn analog output and attached 1.5V, 3.0V and a 9-volt battery. The output from the batteries went through the same shielded cable and into the servo driver. Using the analog signal from the batteries, the servo driv...

Thanks.... Will do.

I do not have an oscilloscope to analyze this. Here is what I know: 1. When running in test or jog mode, the spindle encoder reads a fairly stable rpm. 2. When the servo is controlled by the analog signal, the spindle encoder shows a bouncing, unstable rpm. 3. The servo driver has the ability to dis...

No luck at all. I removed the connectors and now the shielded cable runs directly from Acorn to JMC Servo.... But the signal is still bouncing up and down. Not sure what to try next. Maybe install a few Ferrite Toroid Cores if the noise is coming from the servo driver.

I did some further digging and think I found the culprit. The wire running from the Acorn to the servo exits the enclosure, then passes through a pair of DB9 connectors (Not sure what I was thinking :o ), then proceeds to the servo. The cable is a shielded cable that has drain wire and foil shield. ...

Ok.... I found the document that addresses minimizing EMI for VFD's that I used when I wired this thing originally. See number 15 that I highlighted. This document is from Automation Direct.