Centroid Community CNC Support Forum

Hello,
I’m retrofitting a knee mill with an oak controller and a 4th axis rotary table. I need help figuring out what size control components I should use. I know the size of wire but I’m unsure of relays, breakers, contactors etc. I’ve studied the centroid diagrams and yaskawa manuals but I still don’t understand everything. I can give someone a list of what I have. I’ve read that I need a reactor for the drives and vfd but I don’t see anything on the centroid diagrams, so I’m a bit confused.

Thanks

For better or worse, the vast majority of Yaskawa-drive installations do not use line reactors, and seem to get along fine without them.

Your circuit breakers and contactors should be sized for the rated input current of your drives. Until you know what size drives you are using -- which is determined by what motor power you need -- you cannot know what breakers and contactors to use.

With current Yaskawa components, it is not necessary to use a bank of emergency stop contactors to interrupt line power to each servo drive. Instead, you can install a safety relay, controlled by your emergency stop, which interrupts the safety inhibit on CN8. This is easier on your drives, because the bus capacitors are not discharged and charged every time you cycle emergency stop; and it saves cabinet space and components. I usually use a Dold BH5928 safety relay from Automation Direct, because it has off-delay timed contacts. I use the off-delay contacts for the servo inhibits, so that in a "normal" emergency stop condition (one where the PLC and control software are all functioning correctly) the drives have time to decelerate the motor to a stop before the inhibit circuit opens.

The rated input current for Yaskawa servo drives has historically not been listed in the catalogs; but has been on the data plate on the side of the drives, and has been listed in the "safety precautions" booklet that accompanies the drives.

Have you chosen what motor and drives you want to use yet? Or is that part of the "help with components" you are inquiring about here?