Mike Holt

NEC Trainer / Consultant,
Mike Holt Enterprises

Mike earned a masters degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Since 1975, he has provided custom in-house seminars for groups such as IAEI, NECA, ICBO, IBM, AT&T, Motorola, and the U.S. Navy. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to develop seminars, videos, books, and software as well as contributing monthly Code content to EC&M magazine.

Code Quandaries 1
Q. A new exception was added to 250.50 in the 2005 NEC, which states that concrete-encased electrodes are not required for existing buildings or structures where the conductive steel reinforcing bars aren't accessible without disturbing the concrete. Why was this exception added to the 2005 NEC, and what does this all mean?
Code Q&A
Q. How close can I run underground service conductors in a raceway to an outdoor pool?
Code Q&A
Q.When is a two-pole breaker required for a multiwire branch circuit? A.Multiwire and multiple branch circuits that supply devices or equipment on the same yoke (also called a strap) must be provided with a means to disconnect simultaneously all ...
Grounding vs Bonding — Part 10 of 12
Does the NEC require you to ground piping systems and structural steel? Be careful how you answer this question.
Code Quandaries 1
All questions and answers are based on the 2005 NEC. Q. Can a 15A, 125V receptacle be located above a suspended ceiling? A. Sure. Receptacles are permitted
Code Q&A
Q. Is a switch that is located in a bedroom but controls an outside light required to be AFCI protected? A. No. The requirement of 210.12(B) is that all 15 or 20A, 120V branch circuits that supply outlets in dwelling unit bedrooms must be protected by a ...
Code Q&A
Q. I’m working on an electric gate installation. Can I install control wiring in the same raceway with electrical power conductors? A. Maybe. According to 725.26(B)(1), Class 1 circuits can be placed in the same cable, enclosure, or raceway with ...
Grounding vs Bonding — Part 9 of 12
Do you know when an isolated ground is appropriate and how to properly install it?
Code Quandaries
All questions and answers are based on the 2005 NEC. Q. Where are hospital-grade receptacles required? A. Receptacles for inpatient sleeping beds or procedure
Code Q&A
Q. Can a stranded 12 AWG wire be placed under the screws for receptacles and switches? A. Conductor terminations must comply with manufacturer’s instructions as required by 110.3(B). For example, if the instructions for the device state “Suitable for ...
Code Q&A
Q. What size grounding electrode conductor is required for a 1,200A service supplied with three sets of 600 kcmil conductors per phase? A. When not run to a ground rod, concrete-encased electrode, or ground ring, the grounding electrode conductor must ...
Grounding vs Bonding — Part 8 of 12
Don’t use the equipment grounding conductor for grounding
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 ...

EC&M Learning Center


Newsletter Signup

Connect With Us

Sponsored Introduction Continue on to (or wait seconds) ×