STO Safe Torque Off on a Field Mounted Drive VFD

[GTUnit]

I have a customer with a Garment Hanger Conveyor who intends to put 2 drives inside a panel and a 3rd drive out in the field by the motor.
I would like to use STO with a safety relay for the EStop circuit.
On the drives in the panel, no problem, but how can this be done, in a simple manner, on the drive that is say, 200' from the panel?
I doubt the drives STO circuit support being run all the way back to the panel to the safety relay.

 

[mk42]

I have a customer with a Garment Hanger Conveyor who intends to put 2 drives inside a panel and a 3rd drive out in the field by the motor.
I would like to use STO with a safety relay for the EStop circuit.
On the drives in the panel, no problem, but how can this be done, in a simple manner, on the drive that is say, 200' from the panel?
I doubt the drives STO circuit support being run all the way back to the panel to the safety relay.

Not sure if that's OK or not.



This might be a case where a safety PLC and a drive with networked safety could make sense.

 

[GTUnit]

Not sure if that's OK or not.
This might be a case where a safety PLC and a drive with networked safety could make sense.

I agree but these are small systems for a manufacturer that lacks Controls troubleshooting proficiency so we need to keep these as simple as possible.
They should not need a CE to start these up or troubleshoot common issues that may bring production to a halt.

 

[JeremyM]

I have a customer with a Garment Hanger Conveyor who intends to put 2 drives inside a panel and a 3rd drive out in the field by the motor.
I would like to use STO with a safety relay for the EStop circuit.
On the drives in the panel, no problem, but how can this be done, in a simple manner, on the drive that is say, 200' from the panel?
I doubt the drives STO circuit support being run all the way back to the panel to the safety relay.

(I'm assuming these are PowerFlex 525)

It will work.

You don't have to use the S+ from the drive itself. Just source the dual channel 24V from the cabinet, pass through safety relay, add 24V COM, send all 3 to the drive's S1, S2, and TrmBlk04 terminals respectively.

The drive's safety inputs aren't expecting pulsed signals, so 24V is all that's required. You can even add a local E-Stop in series with this signal.

 

[PLC Pie Guy]

I have a customer with a Garment Hanger Conveyor who intends to put 2 drives inside a panel and a 3rd drive out in the field by the motor.
I would like to use STO with a safety relay for the EStop circuit.
On the drives in the panel, no problem, but how can this be done, in a simple manner, on the drive that is say, 200' from the panel?
I doubt the drives STO circuit support being run all the way back to the panel to the safety relay.

I don't see the issue with this scenario if your wires are large enough to prevent the voltage drop from creeping up there. 200' isn't that far in an industrial environment. I'm sure we have situations where the S1 and S2 for the PF5252 are longer than this.