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gundog
12-06-2011, 09:43 PM
I am running my new to me Trak CNC mill on a static phase converter right now I would like to change it out and use a VFD but I am wondering if it will work well for me? The reason I ask is because of how my controller works in relation to the spindle motor. When my machine completes a toolpath or program the controller turns off the motor or at a tool change the motor is turned off by the controller the controller will not turn on the spindle it only turns it off. Is there a way for the VFD to stay powered up but allow a signal to shut off the motor so that it works the way it is designed? Powering the VFD up and down constantly does not seem like the way to go.

Thanks Mike

lakeside53
12-06-2011, 09:59 PM
Yes, the VFD is always powered up. You will need to wire the VFD only to the spindle motor, then interface whatever is sensing the off condition to the vfd control inputs. Many variables... but it's probably simple. Worst case you will use a relay contact (likely already has one - the spindle motor contactor) to open the NC stop button circuit. Do you have a schematic? You will need to figure if any other part of the system needs 3 phase power - the VFD can't provide this.

gundog
12-06-2011, 10:15 PM
Yes, the VFD is always powered up. You will need to wire the VFD only to the spindle motor, then interface whatever is sensing the off condition to the vfd control inputs. Many variables... but it's probably simple. Worst case you will use a relay contact (likely already has one - the spindle motor contactor) to open the NC stop button circuit. Do you have a schematic? You will need to figure if any other part of the system needs 3 phase power - the VFD can't provide this.

Thanks Lakeside,
It does have a relay for the motor. The spindle motor is the only 3 phase the controller is powered by a separate 110V single phase feed that feeds the servos & coolant pump. I am going to order a Hitachi VFD the one you recommended to me in a previous thread.
Mike