Have you ever compared your NFPA 70 book with a colleague and found that there were differences, though both books were the same edition of the NEC? We know that we receive a new edition of the NEC every three years, but how does the Code change between cycles?
NEC Section 230.71. Six Switches or Circuit Breakers in One Enclosure
Since the 1937 edition of the NEC, the service disconnecting means used to isolate a building’s premises wiring from the utility provider’s conductors has been allowed to consist of as few as one, but as many as six switches or sets of circuit breakers.
A veteran electrician would tell you that requirement (or permission, depending on your perspective) means six throws of the hand can be used to control all power on the property. Our veteran electrician is correct – if there is one electrical service on the property.
Under Floor Electric Cable and Cable Mat Systems are a great way to warm or even heat a space. These systems can be a supplemental or even a main source of heat in a variety of rooms. The systems can be installed under many types of floors such as tile, wood, concrete, vinyl, and even carpet. The manufacturers offer a variety or pre-engineered packaged units and even piece-by-piece options. The manufacturer’s step-by-step installation instructions must be used to install the heating cables, mats, spacers, thermostats, and other associated equipment. The instructions will also point us in the right direction as far as the branch circuit size but will most likely not give all of the needed information.
Bathroom branch circuit requirements have changed for the 2020 Code cycle. The one 20-amp branch circuit traditionally required by NEC Section 210.11(C)(3) to feed only receptacles in dwelling unit bathroom(s) is now restricted to feeding only countertop receptacles in those same bathroom(s).
The receptacles permitted on this newly defined branch circuit include any countertop receptacles required to be within 3 feet of the bathroom’s sink basin and any other receptacle(s) installed to serve countertops or similar work surfaces in these bathroom(s).
Chapter 7 of the 2020 National Electrical Code (NEC), also known as NFPA 70, covers special conditions and their specific requirements. These requirements modify the general requirements found in Chapters 1-4. Article 700 covers emergency systems, such as hospitals or similar settings where a power outage would put lives in jeopardy. Article 701 covers legally required standby systems and Article 702 covers optional standby systems.
The 2020 National Electrical Code (NEC) has ushered in a brand-new method for determining the number of receptacle outlets required to serve island countertops; peninsular countertops; and work surfaces located in kitchens, pantries, breakfast rooms, dining rooms, and similar areas of a dwelling unit.
If you ask a seasoned electrician how many No. 12 AWG conductors will fit into a 3/4″ EMT conduit system, you may get a response such as “one more!” While this is amusing (and typically true), there are precautions that must be taken according to the NEC whenever conductors are bundled together in a raceway, cable, or even in a ditch in the earth.
In this 2020 Code cycle a new Informational Note now accompanies the term Grounded Conductor where it is defined in Article 100. The Note has been added to help electricians identify functional differences between Grounded and Grounding Conductors.
In defense of all who have struggled with these terms in the past, both grounded conductors and grounding conductors are in fact grounded. They just have different jobs.
Section 408.6: A Brand-New Addition to the 2020 NEC
NEC section 408.6 states: Switchboards, Switchgear, and Panelboards shall have a short-circuit current rating (SCCR) not less than the available fault current. In other than one- and two-family dwelling units, the available fault current and the date the calculation was performed shall be field marked on the enclosure at the point of supply. The marking shall comply with 110.21(B)(3).
Making NEC 408.6 Simple
This new Code Section simply means that electrical panels including main-breaker and main-lug type panels and switchboards & switchgear equipment must be rated (in amps) to withstand the high levels of current that will flow should a short-to-ground or other fault occur at the equipment. In ALL locations other than dwelling units, that anticipated fault current must be marked on the equipment enclosure near where the supply conductors enter in, along with the date that the calculation producing that number was performed. The new Code Section also says the markings on the equipment must comply with 110.21(B)(3). Section 110.21(B)(3) tells us that markings must be sufficiently durable to withstand the environment.
Montana electrical licenses will expire on July 15, 2020. To continue working under your Montana electrical license you must complete and application and continuing education courses. Renewal opens 60 days prior to the expiration date.
Don't wait for an Electrical Inspector to teach you the 2023 NEC. Save time, money, and pass inspections the first time by completing our online continuing education courses.