national electrical code

Code Q&A

Feb 26, 2006, By Mike Holt

Q. Is it good practice to bond the lightning protection system to the building grounding electrode system?...

What's Wrong Here?

Feb 26, 2006, By Joe Tedesco

Hint: Use your nose to help sniff out this violation....

What is the maximum number of overcurrent devices permitted in a lighting and appliance branch-circuit panelboard? What is the maximum number of overcurrent devices permitted in a power distribution unit (PDU) of an information technology system?...

Code Q&A

Feb 11, 2006, By Mike Holt

Q. What size wire and breaker is required for an air-conditioner whose nameplate specifies the circuit conductor must have a minimum rating of 44A, with overcurrent protection not to exceed 60A? The terminals on the equipment are rated 75°C....

Code Quandaries

Feb 1, 2006, By Mike Holt, NEC Consultant

Q. Is GFCI protection required for a 15A or 20A, 125V receptacle that is located within 6 feet of a janitorial closet sink in a commercial building?...

Illustrated Catastrophes

Feb 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...

Class and Division: Don't Break Rank on Your Next Installation

Feb 1, 2006, By Mike Holt, NEC Consultant

What exactly is a Class I location? Can you define it, or better yet, easily identify it in the field? You have a Class I location any time enough flammable...

Code Quiz

Jan 25, 2006, By Steven Owen

When installing a grid structure at a dwelling unit swimming pool, the equipotential bonding grid shall cover the contour of the pool and the pool deck...

Code Q&A

Jan 25, 2006, By Mike Holt

Q. What is the largest size transformer permitted to be mounted above a suspended ceiling used for environmental air?...

Code Quiz

Jan 10, 2006, By Steven Owen

An equipotential plane installed at a catfish farm pond is required for the service equipment installed outdoors (adjacent to the pond), where the service equipment controls equipment is installed in and adjacent to the water....

Code Q&A

Jan 10, 2006, By Mike Holt

Q. I understand the Code allows me to use Type AC cable with an equipment grounding (bonding) conductor for branch circuits serving patient care areas. Can I use Type MC cable with an equipment grounding (bonding) conductor for luminaires located above 7.5 feet in a patient care area?...

What's Wrong Here?

Jan 10, 2006, By Joe Tedesco

Hint: Sing along with me. One of these things, doesn’t belong here...

An Inside Look at Hazardous (Classified) Locations

Jan 1, 2006, By Mike Holt, NEC Consultant

When you're looking for answers on hazardous (classified) location questions, where should you turn? Think of Articles 500 through 517 as a mini codebook...

Illustrated Catastrophes

Jan 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...

Code Quandaries

Jan 1, 2006, By Mike Holt, NEC Consultant

Q. I recently came across a handhole with a metal cover in the backyard of a house that is used to splice the underground service conductors. I told the utility mechanic the cover needed to be grounded (bonded) because there could be accidental contact with live circuits....