The Mike Holt Podcast

440.9 Rooftop Air-Conditioning Equipment Grounding Conductor – https://www. MikeHolt.com/code. You may already be aware that metal raceways such as RMC and EMT are suitable equipment grounding conductor types, but what about where roof-top air-conditioning equipment (roof-top units or RTUs) is concerned? Discover the unique requirements for RTUs in this podcast about section 440.9 in the NEC.

406.9(C) has redefined the bathtub or shower “zone” and prohibits the installation of receptacles in this area. Don’t worry, some latitude was added to the rule allowing for receptacles to be installed in bathrooms too small to meet these requirements.

406.(D)(2) Receptacle Replacement, Without Ground Wire – https://www. MikeHolt.com/code. So, you need to replace a receptacle and discover there’s no equipment ground. What are your options? What does the Code allow or require? The fact is that electricity has been coming into buildings for well over a century, and an equipment ground wasn’t always required. It’s only a matter of time before you c...

300.7 Raceways Exposed to Different Temperatures – https://www. MikeHolt.com/code. Where raceways are exposed to different temperatures, section 300.7 of the NEC requires us to take measures to prevent condensation inside the raceways. How this is accomplished, and when and where this rule applies, is the topic of this podcast.

352.44 PVC Expansion Fittings – https://www. MikeHolt.com/code. Who doesn’t like PVC? It’s versatile, lightweight, cost-effective, and easy to install. Did you know that raceways expand and contract to some degree and PVC does much more than RMC, IMC, or EMT? Although sometimes overlooked, expansion fittings are required to accommodate this characteristic and the requirements in section 352.44 of...

90.1 Purpose of the NEC – https://www. MikeHolt.com/code. The National Electrical Code contains the rules and requirements for electrical installations, but why? What’s its true purpose? Find out in this podcast clip as we discuss Code section 90.1.

300.22 Plenum Space Wiring Methods – https://www. MikeHolt.com/code. Nowhere is the risk of the spread of fire more apparent than in the spaces and ductwork that distribute environmental air, or the ductwork that provides different types of exhaust. The types of ducts, plenums, and the special wiring and electrical installation considerations contained within section 300.22 of the NEC are the topi...

404.2(C) Neutral at Switch Locations – https://www. MikeHolt.com/code. If you’re under the impression that all light switch locations are required to contain a neutral conductor, then you’ve been misinformed or maybe you haven’t read the Code. Learn the conditions where light switch locations may, or may not, require a neutral conductor in this podcast about section 404.2(C) in the NEC.

Motor circuits have special requirements that affect how the overcurrent protective device and conductors are sized and installed. So how do we size the conductors and protection? Motor full load current? Nameplate rating? What’s the difference? Find out in this podcast where we explain the motor full-load current ratings contained in Tables 430.248 and 430.250, and how they affect not only conduc...

This podcast is an extract from Mike Holt’s Understanding the 2020 National Electrical Code Complete Training Library. For more information about this product visit https://www. MikeHolt.com/code or call 888.632.2633.

555.35(B) Marina and Boat Dock Leakage Current Measurement Device - https://www. MikeHolt.com/code. Electric shock drowning (ESD) is a frightening killer and anything that can be done to prevent it should be done. That is the intent of the change in 555.35(B) requiring a leakage current meter to be provided on site at docks and marinas to assist in the maintenance of shore power connections. This...

555.13 Marina and Boat Dock Bonding – https://www. MikeHolt.com/code. Increased awareness of the electric shock drowning hazards at docking facilities has prompted another group of changes in this Code cycle. New section 555.13 requires a bonding conductor from the panelboard to connect to all metal parts in contact with the water that are likely to become energized in and about boatyards, marinas...

When interconnected electrical power production sources, such as wind powered generators, solar PV systems, or fuel cells are connected in parallel with utility power, special considerations for safety and efficiency must be made. This makes supply-side source connections a most critical aspect of a safe and compliant installation. This podcast on Section 705.11 explains just what the requirements...

Interconnected Electrical Power Production Systems Sources are connected in parallel with the serving utility with no transfer switch. There are complex requirements to install these systems safely and expert knowledge is required. Learn more about it in this podcast on section 705.13.

Anytime there is more than one source of power supplying a building, safety concerns arise. The rules for Interconnected Electrical Power Production Sources are contained in Article 705 in the NEC. Learn what is covered within this article in this podcast discussing the Scope of Article 705.

90.4 Inspector’s Authority – https://www. MikeHolt.com/code. The National Electrical Code is intended to be suitable for mandatory application by governmental bodies, but just who is responsible for ensuring the Code is followed once adopted? In this podcast on 90.4, we’ll explain what’s meant by the “authority having jurisdiction.”

Often referred to as "redundant grounding", equipment grounding requirements in patient care spaces utilize two different types of equipment grounding conductors so an installation error or component failure won't result in the loss of the effective ground-fault current path. Listen to this podcast to find out which wiring methods meet these NEC requirements.

Hazardous (Classified) Locations are unique because they have additional requirements when installing electrical equipment and circuits. But ? Find out how to identify these locations in this podcast.

250.30 Grounding, Transformers – https://www. MikeHolt.com/bonding. In order to comply with NEC 250.30, you first need to understand what is meant by a “separately derived system” then you will understand what is trying to be accomplished in these Code requirements covered in this podcast.

250.4 Grounding, System and Equipment – https://www. MikeHolt.com/bonding. In this podcast on the “General Requirements for Grounding and Bonding” we’ll discuss bonding and grounding of electrical systems and equipment and explain exactly why these terms have two entirely different meanings and why it is so important that you understand the purposes of the two. We’ll explain electrical system “gro...

250.24 Grounding, Service Equipment – https://www. MikeHolt.com/bonding. Before you can understand the grounding of an electrical service and equipment, you’ll need to understand just what a “service” is. This podcast will explain that and where we go from there to ensure compliance with NEC 250.24.

250.6 Grounding, Objectionable Current – https://www. MikeHolt.com/bonding. What is “objectionable current”? What are it’s causes, can it be prevented and if so, how? In this podcast, we discuss why objectionable current is a dangerous condition and the NEC requirements that serve to mitigate its causes.

250.36 Grounding, High Impedance – https://www. MikeHolt.com/bonding. Did you know that a high impedance grounded ac system cannot serve line to neutral loads? In this podcast, we’ll explain what a high impedance grounded system is, where the impedance must be located, and how it differs from a conventional solidly grounded electrical system.

250.54 Grounding, Auxiliary Grounding Electrode – https://www. MikeHolt.com/bonding. Are auxiliary grounding electrodes required by the NEC? Do they serve any real purpose? The answer(s) is/are, no. Find out why and how they might just do more harm than good in this compelling discussion with our panel of experts!

250.53(A)(2) Ground Resistance Measurement – https://www. MikeHolt.com/bonding. NEC 250.53(A)(2) requires that a single grounding electrode be supplemented by an additional electrode but, is that always the case? Learn the exceptions as well as what qualifies as a supplemental electrode as our panel of experts discuss this topic.