Mike Holt

Code Quandaries
All questions and answers are based on the 2005 edition of the NEC. Q. Where must the system-bonding jumper at a transformer be installed? A. The metal
Code Q&A
Q. How would you size the bonding wire to a motor that’s protected by an inverse time circuit breaker? A. The equipment grounding (bonding) conductor must be sized in accordance with Table 250.122, based on the ampere rating of the circuit-protection ...
Code Q&A
Q. What’s the minimum and maximum height for electrical equipment that contains circuit breakers or switches? A. There is no minimum height for switches and circuit breakers. However, 550.32(F) requires the service disconnecting means enclosure for ...
Grounding vs Bonding — Part 7 of 12
Errors in sizing and installing grounding electrode conductors can cause your entire grounding system to fail
Code Q&A
Q. Must receptacles be installed so they can be removed without interrupting the power to any downstream receptacles? A. Continuity of the grounded neutral conductor of a multiwire branch circuit must not be interrupted by the removal of a wiring ...
Code Q&A
Q. Does the NEC restrict the placement of a light switch in a bathroom? What about pools, spas, and hot tub areas? A. Switches can be located next to, but not within, a bathtub, hydromassage bathtub, or shower space (404.4 and 680.70 and 680.72). ...
Grounding vs Bonding — Part 6 of 12
How solid is your understanding of grounding electrode systems?
Code Q&A
Q. Does the Code require an electric motor driven fire pump to be connected to a standby generator if a standby generator is installed on the premises? A. Power to fire pump motors must be supplied by a reliable source of power (695.3) that has the ...
Code Q&A
Q. Can I terminate two wires on a single-pole circuit breaker? A. Yes, if the terminal is identified for two conductors, either within the equipment instructions or on the terminal itself. It’s my understanding that only Square D circuit breakers (15A, ...
Code Quandaries
Stumped by the Code?
Grounding vs Bonding — Part 5 of 12
Do you know the right way to ground and bond buildings or structures supplied by feeders or branch circuits?
Code Q&A
Q. Does the Code limit the total ampere rating of all circuit breakers in a panel? For example, could the total ampere rating of all circuit breakers in a 100A panel exceed 100A? A. This isn’t a Code issue. The sum of the ampere rating of the circuit ...
Code Q&A
Q. What’s the maximum number of circuit breakers permitted to be installed in a panel? A. The maximum number of circuit breakers permitted in a panelboard is limited by the instructions posted inside the panelboard . In addition, 408.15 specifies that a ...
Grounding vs Bonding — Part 4 of 12
People often forget that all transformers, except autotransformers, are separately derived
Code Q&A
Q. What outlets in a dwelling unit are required to be AFCI protected? A. All 15A or 20A, 120V branch circuits that supply outlets in dwelling unit bedrooms must be protected by a listed AFCI device . According to Art. 100, an outlet is a point in the ...
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