Stumped by the Code
Apr 1, 2009, By Mike Holt, NEC Consultant
Q. We have a 400A, 3-phase feeder that we want to wire with two parallel sets of 3/0 AWG conductors in the same raceway. Is this acceptable?...
Code Q&A
Mar 19, 2009, By Mike Holt
Q. Can the ground wire from a ground rod terminate in the meter socket enclosure, or must it terminate in the service disconnect?...
Code Q&A
Mar 5, 2009, By Mike Holt
Q. What are the NEC lighting and switching requirements for stairways?...
Stumped by the Code?
Mar 1, 2009, By Mike Holt, NEC Consultant
Q. What are the requirements for supporting communications raceways and cables above a suspended ceiling?...
Code Q&A
Feb 19, 2009, By Mike Holt
Q. What are the AFCI protection requirements for dwelling units, and do these requirements apply to smoke alarms?...
Code Q&A
Feb 5, 2009, By Mike Holt
Q. Does the code require GFCI-type receptacles anywhere, or can you use GFCI breakers for all required GFCI locations?...
Stumped by the Code?
Feb 1, 2009, By Mike Holt, NEC Consultant
Q. What are the termination requirements where NM cables enter a panel?...
Code Q&A
Jan 22, 2009, By Mike Holt
Q. In our local high school science lab, receptacles have been installed within 4 in. from the edge of a sink. Is this acceptable per the Code?...
Code Q&A
Jan 8, 2009, By Mike Holt
Q. Where does the Code address which way the grounding terminal of a receptacle goes (up or down)?...
Stumped by the Code?
Jan 1, 2009, By Mike Holt, NEC Consultant
Q. What are the NEC requirements on the use of the white wire for the ungrounded conductor?...
Code Q&A
Dec 4, 2008, By Mike Holt
Q. We had a new swimming pool installed at our house, and the electricians ran a cable to the pool equipment room panel. Is this legal?...
Stumped by the Code?
Dec 1, 2008, By Mike Holt, NEC Consultant
Q. Is GFCI protection required for receptacles above the counter of a break room in an office building?...
Code Q&A
Nov 20, 2008, By Mike Holt
Q. Can a 45 kVA transformer be installed in the ceiling space above the ceiling grid?...
Code Q&A
Nov 6, 2008, By Mike Holt
Q. What is the maximum height that a safety switch can be installed?...
Code Q&A
Oct 23, 2008, By Mike Holt
Q. How do you size the ground wire when running conductors in parallel?...
Code Q&A
Oct 9, 2008, By Mike Holt
Q. Our utility requires a nonfused disconnect upstream of the meter and service disconnect for certain services. Is this legal?...
Stumped by the Code?
Oct 1, 2008, By Mike Holt, NEC Consultant
Q. I have a 1,200A, 480V panel that has a working space of 3½ feet. The engineer says 7 feet is required. Is he correct?...
Code Q&A
Sep 18, 2008, By Mike Holt
Q. We have motors that are interlocked, preventing them from being on at the same time. Do we still have to add them up for service and feeder calculations? ...
Code Q&A
Sep 4, 2008, By Mike Holt
Q. Is a disconnect required to be within sight of electric space-heating equipment if the unit has a factory-installed circuit breaker?...
Code Quandaries
Sep 1, 2008, By Mike Holt, NEC Consultant
Q. What are the requirements for installing fixtures in a bathroom?...
Code Q&A
Aug 21, 2008, By Mike Holt
Q. What is the smallest size wire you can use for a lighting fixture whip?...
Stumped by the Code?
Aug 14, 2008, By Mike Holt, NEC Consultant
Q. Am I required to secure Type MC cable that is located under a raised floor of an information technology equipment room? ...
Code Q&A
Aug 7, 2008, By Mike Holt
Q. What is the maximum number of bathroom receptacles that can be placed on the 20A, 120V bathroom receptacle circuit in a single-family dwelling?...
Code Quandaries
Aug 1, 2008, By Mike Holt, NEC Consultant
Q. When adjusting the ampacity of a conductor due to conductor bundling, do we use the 90°C column ampacity or the 75°C column ampacity as listed in Table 310.16 for THHN?...
