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 are to accomplish this.
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 “grounding” and also equipment “bonding” which essentially means that any current-carrying conductive mat...
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.
210.8 GFCI Protection - https://www.Mikeholt.com/code. There’s no doubt that ground-fault circuit-interrupters have protected many people from electrical hazards. This Code cycle there is an increased emphasis on GFCI protection and many new locations that require GFCI protection have been added. The 2020 changes and revisions to this section are numerous and include clarifications, expansions to existing rules, and a few new items. Some rules were also relocated to and placed in more appropriat...
300.21 Fire-Rated Walls, Ceilings, and Floors – https://www.MikeHolt.com/code. Wherever there’s airflow, the potential for a fire to spread exists. The requirements in section 300.21 of the NEC are designed to prevent, as much as possible, increasing the spread of fire where electrical installations may decrease fire-resistive ratings of walls, ceilings, and floors. In this podcast, you’ll learn what must be done in order to comply with this rule.
A fire pump wouldn’t be of much use during a fire if the circuit conductors that supply it failed. Sizing these conductors isn’t the same as sizing other motor conductors. Listen to this podcast to ensure that you’re sizing fire pump circuit conductors correctly.
Service conductors supplying the entire load associated with a dwelling unit can be sized in accordance with Table 310.12 but are there any rules or considerations before using this table? What about if it’s a feeder instead? The answers to these and many other questions can be found by listening to this podcast on sizing these service/feeder conductors.
250.122 Equipment Grounding Conductor, Sizing – https://www.MikeHolt.com/bonding . The equipment grounding conductor sizes for 15A -30A circuits are easy to remember since they are required to be full sized and are part of cable assemblies. Larger circuits, however, typically require the use of Table 250.122 and that can be a little confusing. Listen to this podcast to better understand how these conductors are sized....
250.119 Equipment Grounding Conductor Types – https://www.MikeHolt.com/bonding . Equipment grounding conductors can be identified in several ways. In this video clip, we discuss how the NEC requires these conductors to be identified....
There is now so much sustainable electrical energy being produced that we need to find ways to store it! An Energy Storage System (ESS) consists of one or more components capable of storing electrical energy for future use. Article 706 in the NEC covers the requirements for ESS and it’s important to understand what Article 706 does and does not apply to. Find out why in this podcast on the Scope of Article 706.
For most of us, a loss of utility or normal electrical power is an inconvenience and is usually restored as soon as humanly possible. But where electrical power is essential for maintaining safety to human life, an emergency electrical system is required. Do you know what types of occupancies might require this consideration and who classifies these systems as emergency? To answer these questions and fully understand what distinguishes an ‘Emergency System’ from a ‘Backup System, read the attach...
For years, a common practice for one and two-family dwellings has been to install a meter enclosure outside and main breaker panel suitable for use as a service disconnect inside. As electrical professionals, many of us had that hunch to ask ourselves, "what about first responders." A recently added Code rule now requires an emergency disconnect for ALL one and two-family dwellings regardless of the panel's location indoors. But what are the requirements of this new rule? Can the service disconn...
Electric vehicles have been around for a long time. With bi-directional transfer of electrical power from your electric vehicle to your home becoming commonplace, the industry has had to adapt and the scope of Article 625 has changed again. Listen to this podcast to learn the scope of what’s covered in this article and what has changed since the last cycle.
250.122(F) EGC for Parallel Conductors, Sizing – https://www.MikeHolt.com/bonding. One of the costliest mistakes made in electrical installations is a failure to read and fully understand the Code rules for sizing and installing the EGC when paralleling conductors. Read your Code book while listening to this podcast and you could wind up saving yourself a huge amount of aggravation and money!
When three conductors are pulled into a raceway, they may flatten out creating a condition where the conductors could jam. In this podcast we’ll explain how to avoid this condition.
Factors that impact conductor sizing include not only conductor ampacity and equipment terminal temperature rating, but also the conductor insulation temperature rating. In this podcast we discuss Table 310.4(A) which provides information on conductor insulation properties such as letter type, maximum operating temperature, application, insulation, and outer cover properties.
To understand when to apply the requirements of Article 725 for remote-control and signaling circuits, you need to understand the Scope of this article. Listen to this podcast and discover what distinguishes “Class 1” from “Class 2” and “Class 3” circuits and what this article applies to.
210.4 Branch Circuit, Multiwire – https://www.MikeHolt.com/code . Multiwire branch circuits are an efficient and cost-effective approach to installing electrical circuits, but there are inherent hazards when this wiring method is used. In this podcast, we discuss how important it is for these circuits to be installed and serviced properly, and the consequences for failing to do so!...
810.21 Bonding, Radio Antenna Grounding – https://www.MikeHolt.com/bonding . You may be surprised at the number of CB and HAM radio operators there are around the country. These radio frequencies require line-of-sight antenna which requires a substantial height (some are hundreds of feet tall) to maintain that line-of-sight. You can probably already figure out that these heights make them a prime target for lightning strikes. Watch this video clip to help you comply with the Code rules for groun...
