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Box Fill CalculationsNov 1, 2008 12:00 PM, By Mike Holt, NEC Consultant Box fill isn't just the number of wires in the box — it's the total volume of the conductors, devices, and fittings in a box.... |
What's Wrong Here?Correctly identify the Code violation in this month's photo, and you could win a set of insulated hand tools from Ideal Industries, Inc. valued at more than $125.... |
Box Fill Calculations
Nov 1, 2008, By Mike Holt, NEC Consultant
Box fill isn't just the number of wires in the box — it's the total volume of the conductors, devices, and fittings in a box....
Illustrated Catastrophes
Nov 1, 2008, 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)....
Sizing Junction Boxes
Oct 1, 2008, By Mike Holt, NEC Consultant
The sizing requirements for pull boxes, junction boxes, handhole enclosures, and conduit bodies exist to prevent conductor insulation damage. Those requirements...
Illustrated Catastrophes
Oct 1, 2008, 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...
What's Wrong Here?
Oct 1, 2008, By Joe Tedesco, NEC Columnist
How well do you know the Code? Think you can spot violations the original installer either ignored or couldn't identify? Here's your chance to moonlight...
Stumped by the Code?
Oct 1, 2008, By Mike Holt, NEC Consultant
All questions and answers are based on the 2008 NEC. Q. I have a 1,200A, 480V panel that has a working space of 3 feet. The engineer says 7 feet is required....
Motor Calculations
Sep 1, 2008, By Mike Holt, NEC Consultant
To prevent a motor from burning up, you must provide a means of protecting it from overcurrent (overload, short circuit, or ground fault). If you can remember not to confuse motor protection with circuit protection, you’ll eliminate a major point of confusion in motor calculations....
Illustrated Catastrophes
Sep 1, 2008, 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)....
Fill 'Er Up
Aug 14, 2008, By Mike Holt, NEC Consultant
Raceways must be large enough to hold conductors without overheating and avoid insulation damage during conductor pulls. Therefore, we must determine the maximum number and size of conductors to put in a given raceway. That limit is what we mean by raceway fill....
Conductor Size Matters
Aug 1, 2008, By Mike Holt, NEC Consultant
The NEC provides minimum size requirements for conductors to prevent overheating and fire....
Illustrated Catastrophes
Aug 1, 2008, By Joe Tedesco, NEC Columnist
Alan Christofk, a superintendent with Gephart Electrical Construction in Stillwater, Minn., found this unique installation at a gas station...
Article 600: Electric Signs and Outline Lighting
Jun 1, 2008, By Mike Holt, NEC Consultant
Every commercial occupancy needs a form of identification, the standard method of which is typically the electric sign. This is one reason why you'll be working with Art. 600 if you do much commercial or industrial work....
Cathodic Protection Systems and the NEC
Jun 1, 2008, By Whitt L. Trimble and Eddie Guidry, Fluor Enterprises, Inc.
During the 2005 National Electrical Code (NEC) review cycle, a relatively simple revision was made that created a significant change on the cathodic protection (CP) systems of petroleum and chemical facilities (plants)....
Illustrated Catastrophes
Jun 1, 2008, By Joe Tedesco, NEC Columnist
Gary Parker, P.E., Burns & McDonnell, Centennial, Colo., found a circuit breaker panel installation that's gone through a few changes that do not comply with the NEC....
Ohio Home Builders Fight 2008 NEC Adoption
Jun 1, 2008,
The purpose of the National Electric Code (NEC) is the practical safeguarding of persons and property from the hazards arising from the use of electricity....
UL 1449 and the 2008 NEC
Jun 1, 2008, By Joseph DeGregoria, Underwriters Laboratories
The use of surge protective devices (SPDs) within residential, commercial, and industrial applications has sharply increased over the last decade...
Article 450: Transformers and Transformer Vaults
May 1, 2008, By Mike Holt, NEC Consultant
The operation of any facility depends on power distribution, which, in turn, depends on transformers. Safe and reliable operation of transformers is crucial...
Illustrated Catastrophes
May 1, 2008, 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 424: Fixed Electric Space Heating
Apr 1, 2008, By Mike Holt, NEC Consultant
Considering the fact that it has nine parts, at first glance, Art. 424 might seem like overkill for a device as simple as a heater. Walk into any hardware...
