New information about Disconnects for Multiwire Branch Circuits and GFCI, AFCI, and ground fault protection
from electrician2.com
Today I went to a local electrical supply house and bought the square D handle ties for QO circuit breakers labeled QO1HT. The instructions for these handle ties state that they can only be used for two single pole circuit breakers, not three.
I am in process of upgrading the change video for this change in the 2008 NEC in Section 210.4(B) that now requires that multi-wire branch circuit have a simultaneous disconnecting means located at the origin of the circuit.
While discussing the requirements that dwelling unit 15- and 20- ampere 120 volt circuits must all be protected by either a AFCI or a GFCI, the use of handle ties with these types of single pole circuit breakers appears to be forbidden. The GFCI single pole breakers definitely cannot be used for a multiwire branch circuit, but there is no concrete rule that I can find for the AFCI circuit breaker. Using two single pole AFCI circuit breakers with a handle tie for a multi-wire branch circuit is definitely a practice that should be avoided unless there are manufacturer’s instructions that state that it is acceptable.
Another comment brought out something that should be addressed. The statement that all 15- and 20- ampere 120 volt circuits in a dwelling unit must be either AFCI or GFCI protected except for the heating cables used on roofs or permanently installed fire alarm panels needs some qualifications.
The exception for the snow melting or deicing equipment is at 210.8 (A)(3). This exception states: receptacles that are not readily accessible and are supplied by a dedicated branch circuit for electric snow-melting or deicing equipment shall be permitted to be installed in accordance with 426.28. 426.28 states: Equipment Protection. Ground-fault protection of equipment shall be provided for fixed outdoor electric deicing and snow-melting equipment, except for equipment that employs mineral-insulated, metal-sheathed cable embedded in a noncombustible medium.
Therefore this receptacle still requires ground fault protection, but in this case the ground fault protection could be a 30 ma Class B ground fault protector instead of the Class A 5 ma protection.
The other exception for burglar or fire alarms is in 210.8(5) for unfinished basements. The is exception states: A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit-interrupter protection.
Summarizing, then the only receptacle in a dwelling unit that is not required to be either AFCI or GFCI OR ground fault protected is a receptacle supplying only a permanently installed fire alarm or burglar alarm system located in an unfinished basement.
Today I went to a local electrical supply house and bought the square D handle ties for QO circuit breakers labeled QO1HT. The instructions for these handle ties state that they can only be used for two single pole circuit breakers, not three.
I am in process of upgrading the change video for this change in the 2008 NEC in Section 210.4(B) that now requires that multi-wire branch circuit have a simultaneous disconnecting means located at the origin of the circuit.
While discussing the requirements that dwelling unit 15- and 20- ampere 120 volt circuits must all be protected by either a AFCI or a GFCI, the use of handle ties with these types of single pole circuit breakers appears to be forbidden. The GFCI single pole breakers definitely cannot be used for a multiwire branch circuit, but there is no concrete rule that I can find for the AFCI circuit breaker. Using two single pole AFCI circuit breakers with a handle tie for a multi-wire branch circuit is definitely a practice that should be avoided unless there are manufacturer’s instructions that state that it is acceptable.
Another comment brought out something that should be addressed. The statement that all 15- and 20- ampere 120 volt circuits in a dwelling unit must be either AFCI or GFCI protected except for the heating cables used on roofs or permanently installed fire alarm panels needs some qualifications.
The exception for the snow melting or deicing equipment is at 210.8 (A)(3). This exception states: receptacles that are not readily accessible and are supplied by a dedicated branch circuit for electric snow-melting or deicing equipment shall be permitted to be installed in accordance with 426.28. 426.28 states: Equipment Protection. Ground-fault protection of equipment shall be provided for fixed outdoor electric deicing and snow-melting equipment, except for equipment that employs mineral-insulated, metal-sheathed cable embedded in a noncombustible medium.
Therefore this receptacle still requires ground fault protection, but in this case the ground fault protection could be a 30 ma Class B ground fault protector instead of the Class A 5 ma protection.
The other exception for burglar or fire alarms is in 210.8(5) for unfinished basements. The is exception states: A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit-interrupter protection.
Summarizing, then the only receptacle in a dwelling unit that is not required to be either AFCI or GFCI OR ground fault protected is a receptacle supplying only a permanently installed fire alarm or burglar alarm system located in an unfinished basement.
posted by Gerald Newton at 7:28 PM
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