national electrical code

Code Q&A

Oct 25, 2006, By Mike Holt

Q. Do I have to use bonding jumpers around listed reducing washers?...

Code Quiz

Oct 11, 2006, By Steven Owen

What is the proper size branch-circuit, short-circuit, ground-fault protective device required for a hermetic compressor with a nameplate rated load of 38A?...

Grounding and Bonding of Separately Derived AC Systems

Oct 11, 2006, By Mike Holt

Code Q&A

Oct 11, 2006, By Mike Holt

Q. If an outdoor generator has a disconnect, do I need an additional disconnect where the conductors enter the building?...

Illustrated Catastrophes

Oct 1, 2006, By Joe Tedesco, NEC Columnist

As usual, never consider the following commentary associated with these photos as a formal interpretation of the National Electrical Code (NEC). Without...

Article 725: Around the Circuit Part 2

Oct 1, 2006, By Mike Holt, NEC Consultant

In last month's Code Basics article, starting on page 56 of the September issue, we spent most of our time discussing Class 1 circuits. Now, it's time...

Code Quiz

Sep 25, 2006, By Steven Owen

What is the minimum size XHHW insulated feeder conductor permitted for an industrial machine, which consists of the following loads? All terminals are rated at 75°C....

Code Q&A

Sep 25, 2006, By Mike Holt

Q. Can I use 12-3 NM cable to wire the bathroom GFCIs and laundry circuit in a dwelling?...

Grounding & Bonding Requirements

Sep 8, 2006, By Mike Holt

You basically perform work on two types of systems: solidly grounded or ungrounded. The general requirements for grounding and bonding these systems can be summarized as follows...

Code Quiz

Sep 8, 2006, By Steven Owen

What is the maximum allowable ampacity of 12 AWG THHN insulated conductors installed in a strut-type channel raceway that is 1½ inches by 1½ inches?...

Code Q&A

Sep 8, 2006, By Mike Holt

Q. I recently saw an advertisement for red conduit that is to be used for emergency circuits. Is this a Code requirement?...

Code Quandaries

Sep 1, 2006, By Mike Holt, NEC Consultant

Q. What size conductor is required for a 25-hp, 208V, 3-phase fire pump motor?...

Illustrated Catastrophes

Sep 1, 2006, By Joe Tedesco, NEC Columnist

As usual, never consider the following commentary associated with these photos as a formal interpretation of the National Electrical Code (NEC). Without...

Article 725: Around the Circuit Part 1

Sep 1, 2006, By Mike Holt, NEC Consultant

Any time you are working with burglar alarm, access control, sound, nurse call, or intercom systems, as well as computer networks, lighting dimmer controls,...

When installing a new service for a separate building constructed on the top floor of a parking garage, it has been determined that the service conductors will have to be installed in rigid metal conduit (RMC) starting in the vault below grade of the first floor level of the parking garage...