Mains Noise

[Mooser]

Hello all
I'm slowly converting a small engine lathe to NC and have just completed the Z-Axis. The problem I'm seeing is that when the two 203V's are powered, the radio in the shop goes all static.
When the control (c11g) is on and everything else is powered up it's fine, only when I enable the drives (they are on a separate switch).
I through a ferite ring onto the main (120v) wire from the wall to no affect.
Should I look at the power-supply to gecko or gecko to motor (actually it does that without the motor connected so I guess that's out.
Anyways, performance is ok but the static on the radio has got to go.
Any ideas?
Thanks
Mooser

[Crevice Reamer]

Hi Mooser.

Does your PSU use a torroidal transformer? Uh, are you saying you have a switch on the DC power to the drives?

CR.

[Mooser]

Yeah, toroidal trans down to 36v, two 203v's, one at 7amp and the other at 5 (only the 7 working right now but the 5 is hooked up, just no motor)
The way I've wired the control is that the main power turns on the c11g, cooling fans, etc but not the power to the 203v's
There is a momentary push button that activates a mag-relay that switches the AC side of the trans (and a emergency stop to break the relay coil to turn it off)
I did some poking around tonight and when the gecko's are pulsing (axis is moving) the static seems to be gone or greatly reduced, it's when they are holding the motors that the static shows up.
Tomorrow I'm going to wire a 5v to the enable on the gecko to let the motor freewheel while still having power applied to see what that does.
Could it somehow be feeding back though the shop wiring to the radio, I've check the outlets and they are all wired and grounded (or were when the shop was wired back a few years ago)
?????????????
Mooser

[jsheerin]

Try to eliminate components one at a time to see what's causing the problem. Start with just the power supply (no 203's hooked up). If no noise, hook up the 203's (no cables and motors), etc. If just the PSU causes noise, is it in a grounded metal enclosure? If the motors and cables, are the cables shielded and grounded at one end?

[mactec54]

Hi Mooser

The only thing you have to do is use shielded cable's & Ground the input end of the shields only