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110.26 Working Space about Electrical Equipment – https://www.MikeHolt.com/code. Clearances and working space around electrical equipment are necessary to provide a safe working environment for electrical professionals. The rules that are in place to ensure this space is available are often misunderstood. Be sure you understand these requirements as we discuss Part II of Article 110 in the NEC; more specifically, section 110.26.
According to 110.3(B) in the NEC, equipment, including conductors, must be installed in accordance with the manufacturer's instructions. But what about when the length of these conductors creates a voltage drop? Is voltage drop just a recommendation in the NEC and not really enforceable? Find out in this podcast where we discuss the ramifications of voltage drop in branch circuit and the energy and life safety issues that may be affected.
406.12 Tamper-Resistant Receptacles - https://www.MikeHolt.com/code. The locations where tamper-resistant receptacles are required have been greatly expanded in 406.12 to include all education facilities, areas where people are awaiting transportation, dormitory units, and assisted living facilities.
312.8 Splices in Panel Enclosures – https://www.MikeHolt.com/code. When it comes to electrical enclosures, “As long as we can get the cover on, we're good.” is the mindset of many. The NEC has requirements for fill or how much space inside an enclosure is available for wiring and electrical devices as you'll see when you listen to this podcast on section 312.8.
The 2020 Code cycle brought many changes to Article 690, Solar Photovoltaic (PV) Systems. Some of the more notable changes were in section 690.12 for "Rapid Shutdown" and are discussed in this podcast.
Do you know how a Grounding Electrode System works? What about grounding for PV Systems? Is a grounding system even required? The answers to these questions and more can be found in this podcast.
Bonding and Grounding of PV Equipment is a requirement in Section 690.43 of the NEC and references sections in Article 250. Find out how to ground the equipment and why it needs to be done!
If you've pulled wire into a raceway, you understand the reason to have limits on the wire fill for raceways. In this podcast, we'll discuss the most common condition, where multiple conductors of the same size are installed together in a raceway and the maximum number of conductors permitted can be determined from the tables in Annex C.
230.67 Service Equipment Surge Protection - https://www.mikeholt.com/code. This new section requiring the installation of a surge-protective device (SPD) for all dwelling unit services has been a long time coming. Up until now, dwelling unit surge protection has been optional and usually an “extra” for the electrician. Section, 230.67, now requires surge protection for all dwelling unit services to protect sensitive life safety devices like smoke and CO detectors from surge damage.
230.71 Service Disconnects, Six Maximum – https://www.MikeHolt.com/code. When it comes to service disconnects, the rule of six movements of the hand is pretty well established but, can there ever be more than six? Just how does the NEC define a “service” and does this definition allow for more than six service disconnects? In this podcast on section 230.71, we discuss the requirements regarding the maximum number of service disconnects.
230.71 Service Disconnecting Means - https://www.MikeHolt.com/code. Although the rule of six grouped service disconnects didn't change, disconnects are now required to be compartmentalized to reduce the hazards associated with arc-flash and arc-blast. This might not seem like a big change but, it makes most of the available multi-meter centers and switch boards ineligible for use to meet these requirements.
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 come across this situation and listening to this podcast on section 406.4(D)(2) of the NEC will help you to know how to handle changing out a receptacle where there's no equipment ground present
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 the NEC are the topic of this podcast.
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 topics of this podcast.
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 conductor sizing but also the overcurrent protection requirements of Table 430.52.
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 isn't a solution to the problem but a commendable effort was made to keep the owners and users of docking facilities safe.
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.