Recently installed a new sub panel for the fueling islands that is controlled by a shunt trip breaker in the main panel. The shunt trip breaker is tripped when the emergency shut off switch is tripped. The sub panel contains 4 switch neutral breakers for the gas dispensers. The shunt trip breaker when tripped kills the power to the subpanel but does nothing to the neutrals. Is it required that the neutrals be disconnected from the main panel also?
Emergency Shut off switch at service stations
- Thread starter mr21
- Start date
- Status
- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
Re: Emergency Shut off switch at service stations
Unless the shunt-trip breaker disconnects the panel feeder's grounded conductor from it's source, what you are describing is a functional violation of 514.11(A).
Unless the shunt-trip breaker disconnects the panel feeder's grounded conductor from it's source, what you are describing is a functional violation of 514.11(A).
hardworkingstiff
Senior Member
- Location
- Wilmington, NC
Re: Emergency Shut off switch at service stations
IMO, using a shunt-trip breaker for an E-Stop is asking for trouble. If you lose the control circuit for the shunt, your E-Stop is inoperable and you won't know it until you need it.
I've always preferred to us a closed contact to maintain power to a coil and let the E-Stop switch break that coil power. If you lose your control circuit, your gas quits working.
Oh, yes you must disconnect the neutral with the hots.
IMO, using a shunt-trip breaker for an E-Stop is asking for trouble. If you lose the control circuit for the shunt, your E-Stop is inoperable and you won't know it until you need it.
I've always preferred to us a closed contact to maintain power to a coil and let the E-Stop switch break that coil power. If you lose your control circuit, your gas quits working.
Oh, yes you must disconnect the neutral with the hots.
- Status