Multiple Pole disconnecting means
- Thread starter alterrex
- Start date
- Status
- Location
- Bremerton, Washington
Re: Multiple Pole disconnecting means
Basically yes, without knowing what it is for, I can't site a code rule.
Controller disconnect see 430.102(A)
Motor disconnect see 430.102(B)
Basically yes, without knowing what it is for, I can't site a code rule.
Controller disconnect see 430.102(A)
Motor disconnect see 430.102(B)
Re: Multiple Pole disconnecting means
Thanks so much for you reply. The equipment is specifically boiler sootblowing equipment-an inserting / retracting lance driven by a 480 volt motor controlled by a reversing starter. There are eighteen identical machines. Travel limit switches are mounted at each end of the lance carriage structure to cause reversal at full insertion and shutoff at full retract. Each machine has a local reversing starter and is remotely controlled by one PLC. The 120 VAC control power for the reversing starters and travel limit switches is provided by this PLC's control circuit. There is a disconnect switch on each machine's local control cabinet. This switch interrupts the 480 VAC motor feed only.
The problem I am attempting to alleviate is a safety issue: When technicians work on this equipment a tagout is taken on the local disconnect. This still leaves the control circuit energized from the PLC. I wish to add poles to this disconnect, which is an IEC type having the ability to accept adder decks, making it a perfect candidate to add contacts to interrupt the control circuit.
The issue in question is whether or not I can "mix voltages" on the same switching device.
Thanks so much for you reply. The equipment is specifically boiler sootblowing equipment-an inserting / retracting lance driven by a 480 volt motor controlled by a reversing starter. There are eighteen identical machines. Travel limit switches are mounted at each end of the lance carriage structure to cause reversal at full insertion and shutoff at full retract. Each machine has a local reversing starter and is remotely controlled by one PLC. The 120 VAC control power for the reversing starters and travel limit switches is provided by this PLC's control circuit. There is a disconnect switch on each machine's local control cabinet. This switch interrupts the 480 VAC motor feed only.
The problem I am attempting to alleviate is a safety issue: When technicians work on this equipment a tagout is taken on the local disconnect. This still leaves the control circuit energized from the PLC. I wish to add poles to this disconnect, which is an IEC type having the ability to accept adder decks, making it a perfect candidate to add contacts to interrupt the control circuit.
The issue in question is whether or not I can "mix voltages" on the same switching device.
tony_psuee
Senior Member
- Location
- PA/MD
Re: Multiple Pole disconnecting means
alterrex,
If the disconnect is IEC style, rotary, it hopefully has the capability to have auxiliary contact blocks mounted on the side. If it doesn't there a several companies that make them that do. That is what we use for 120V signal wiring to interlock with the disconnect's position. So, you do maintain some physical seperation of the 120 and 480 while having a contact open or closure based on the disconnect position.
Tony
alterrex,
If the disconnect is IEC style, rotary, it hopefully has the capability to have auxiliary contact blocks mounted on the side. If it doesn't there a several companies that make them that do. That is what we use for 120V signal wiring to interlock with the disconnect's position. So, you do maintain some physical seperation of the 120 and 480 while having a contact open or closure based on the disconnect position.
Tony
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