Motor Safety Circuit

Looking to add 4 motors to an existing cabinet that has a safety compactlogix plc with IO to spare. Boss wants to use the new Allen Bradley E300 overload relays so we can monitor current without using the current ring and conditioner we normally use.

These 4 motors need to be part of the safety system and I see on all rockwell's motor examples they have 2 of their red safety contactors in series with a motor in most of their examples.

My question is will I need 2 red contactors in series with the standard contactor and the e300 or can I do 1 safety contactor and then the standard contactor and E300?

How much would that change the safety level of the circuit?

Is it best for the safety contactor to go above or below the standard contactor? I don't see any of rockwell examples with a standard contactor.

We would have the allen bradley circuit protection breaker on top and linked to the standard contactor also if that matters?

Hi Tim, You need to identify the required 'Safety Category' then design the electrical control circuit around that. Cat 3 and Cat 4 requires two isolating contactors.

The overload and/or circuit breakers have nothing to do with safety.