The Electrical Code

Because article 100 is so extensive, it adds so much value to the readers. But it needs to be broken up in parts. A thru C, D thru G, and so on. Here we go.

Dead Front. To start with this blog we look at what needs no explanation and that is when a person stand in front of a piece of equipment we need to secure that location so not to let that person be in danger.

“Without live parts exposed to a person on the operating side of the equipment. (CMP-9)”

Demand Factor. The total amount of amps vs what the system is demanding. You see this in main panels where the total amount of breaker can add up to 280 to 300 amps and the main breaker is rated at 150 amps. The code uses a calculation and that will be explain in future blog post.

“The ratio of the maximum demand of a system, or part of a system, to the total connected load of a system or the part of the system under consideration. (CMP-2)”

Device. I don’t think I need to explain this, right. Example are radio, TV, compressor, microwaves, etc…..

“A unit of an electrical system, other than a conductor, that carries or controls electric energy as its principal function. (CMP-1)”

Disconnecting Means. This is used to give people who service equipment a means to safely turn the power off that doesn’t allow others to turn it back on by accident. It also allows people to stop the power when equipment is having problems. The code also look at this for the fire department where the power need to be eliminated for a dwelling from a location.

“A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply. (CMP-1)”

Dust-Ignitionproof [as applied to Hazardous (Classified) Locations]. Chemical plants. Wood working shops use these application. Things like that.

“Equipment enclosed in a manner that excludes dusts and does not permit arcs, sparks, or heat otherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmospheric suspensions of a specified dust on or in the vicinity of the enclosure. (CMP-14)”

Dusttight. Dose not allow dust to enter the device or enclosure so that if an arch was to happen will not cause an explosion inside that box or termination point.

“Enclosure construction so that dust will not enter under specified test conditions.(CMP14)

Informational Note No. 1: Enclosure Types 3, 3S, 3SX, 4, 4X, 5, 6, 6P, 12, 12K, and 13, per ANSI/NEMA 250-2014, Enclosures for Electrical Equipment, are considered dusttight and suitable for use in unclassified locations and in Class II, Division 2; Class III; and Zone 22 hazardous (classified) locations. Informational Note No. 2: For further information, see ANSI/
ISA-12.12.01-2013, Nonincendive Electrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous
(Classified) Locations.”

Duty, Continuous. When a device is constantly in demand to operate that needs a lot of power. Not just hospitals but in some homes where the demand for an oxygen for a patient is critical. Not every one will have a redundant(back up) devices that they can go to if the main one breaks, or needs service.

“Operation at a substantially constant load for an indefinitely long time. (CMP-1)”

Duty, Intermittent. This is important because it deals with the Demond factor. For example an AC circuit will run on and off. This frees up the amps from that device for a time.

“Operation for alternate intervals of (1) load and no load; or (2) load and rest; or (3) load, no load, and rest. (CMP-1)”

Duty, Periodic. When a commercial location opens everything is turned on and business begins. There is a demand for devices to run continuously.

“Intermittent operation in which the load conditions are regularly recurrent. (CMP-1)
Duty, Short-Time. Operation at a substantially constant load for a short and definite, specified time. (CMP-1)”
Duty, Varying. When a load needs more time on then off or more time off then on. Look there will be times in the season when dehumidifiers need to work 24 hours a day to eliminate the humidity from the area. Then there will be times that it will be off for days.

“Operation at loads, and for intervals of time, both of which may be subject to wide variation. (CMP-1)”
Dwelling, One-Family. So a one family has some freedoms that a two or more don’t have and that is the ability to do the work with out being a licensed contract of a specific field. Where because of the liability the owner of a multi family has to the other occupants of the dwelling.

“A building that consists solely of one dwelling unit. (CMP-1)”
Dwelling, Two-Family. Things change, but not so drastic, for a two family. They still can fix things just they are limited by the complexity of the job or repair.

“A building that consists solely of two dwelling units. (CMP-1)”
Dwelling, Multifamily. Here the owner of this type of dwelling has there hands tied to contractors. Three or 150 units things change at three.

“A building that contains three or more dwelling units. (CMP-1)”

Dwelling Unit. So the code will need to specify what a home is here. And we do this so that if it becomes damaged and the person tries to live there the jurisdiction have authority has a place in the code book where they can explain to the home owner that if any number of these thing are missing from the dwelling then it no longer is habitable.

“A single unit, providing complete and inde‐ pendent living facilities for one or more persons, including permanent provisions for living, sleeping, cooking, and sanitation. (CMP-2)”

Effective Ground-Fault Current Path. Wow a mouth full. So to dissect this paragraph we will go sentence to sentence, and word for word. Something that is built just to allow power to run through it. With no resistance, and the ability to carry the amount of power from a point(any place in the wire) to where the power is being used to the breaker or Ground fault interrupter(GFI). Pools are a big deal and the code is very specific on this. So to is spa’s and and place there is a danger to the public.

“An intentionally constructed, low-impedance electrically conductive path designed and intended to carry current under ground-fault conditions from the point of a ground fault on a wiring system to the electrical supply source and that facilitates the operation of the overcurrent protective device or ground-fault detectors. (CMP-5)”

Electric Power Production and Distribution Network. This deal with public utilities, and will not go over this because you have no business being in that situation if you need me to expand on the definition for utility power.

“Power production, distribution, and utilization equipment and facilities, such as electric utility systems that deliver electric power to the connected loads, that are external to and not controlled by an interactive system. (CMP-13)”

Electric Sign. In an state there are signs that are powered be utility or through solar. Towns are running a government that sometimes need to install signage to comply with federal regulation. If they don’t they will loose federal funding. I herd this podcast about round about vs a conventional four point intersection. The cost of a four point intersection cost close to 1 million dollars by the time its all set up. Crazy!!!

“A fixed, stationary, or portable self-contained, electrically operated and/or electrically illuminated utilization equipment with words or symbols designed to convey information or attract attention. (CMP-18)”

Electric-Discharge Lighting. Lights have electronic that hold a charge(Capacitors) even when the power is off the device can have a potential to give off energy that can hold enough charge to be lethal to a human. So we need to remember to discharge those devices when working on them or getting rid of them.

“Systems of illumination utilizing fluorescent lamps, high-intensity discharge (HID) lamps, or neon tubing. (CMP-18)”

Electrical Circuit Protective System. Any system that protects the integrity of circuits within that system. I am beginning to sound like the authors of the code book.

“A system consisting of components and materials intended for installation as protec‐ tion for specific electrical wiring systems with respect to the disruption of electrical circuit integrity upon exterior fire exposure. (CMP-16)”

Electronically Actuated Fuse. An interruption of power when a circuit goes into over amp is unusual when the system is built correctly. A motor at start up draws more power and will trip a normal breaker. This type of interrupter will see the over amp and wait to open. This is a time delay that happens hinders if not thousands of times and these fuse open when that time comes. These fuses come all sizes for just about every application imaginable.

“An overcurrent protective device that generally consists of a control module that provides current-sensing, electronically derived time–current character‐ istics, energy to initiate tripping, and an interrupting module that interrupts current when an overcurrent occurs. Such fuses may or may not operate in a current-limiting fashion, depending on the type of control selected. (CMP-10)”

Enclosed. Every situation in every install we see has a different situations that require us to use different sizes enclosures. So when looking at a install many variables need to be accounted for. There are standard sizes in how enclosures come, enclosures can be ordered outside of those sizes but that takes time to get. So that should be accounted for when figuring the time frame of any job.

“Surrounded by a case, housing, fence, or wall(s) that prevents persons from accidentally contacting energized parts. (CMP-1)”
Enclosure. “The case or housing of apparatus, or the fence or walls surrounding an installation to prevent personnel from accidentally contacting energized parts or to protect the equip‐ ment from physical damage. (CMP-1)
Informational Note: See Table 110.28 for examples of enclosure types.”
Energized. I was confused when I first read this, to me energized meant that it has power. When reading the code definition to energized it says electrically connected to and yes when the electricity is on it is energized, when the power is turned off you have a de-energized circuit.

“Electrically connected to, or is, a source of voltage. (CMP-1)”
Equipment. Very general term that is used in the code book to describe many thing through out the code book.

“A general term, including fittings, devices, appli‐ ances, luminaires, apparatus, machinery, and the like used as a part of, or in connection with, an electrical installation.(CMP-1)”

Explosionproof Equipment. This equipment is used in gas stations, medical facilities, chemical labs, and anywhere there is a chance of an explosive gas or vapor to come close to an arch that a switch, and contactors, and other devices can have in start up or shut down.

“Equipment enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby. (CMP-14)
Informational Note: For further information, see ANSI/ UL 1203-2009, Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations.”

Exposed (as applied to live parts). NFPA 70e was written for safe work place conditions.

“Capable of being inadvertently touched or approached nearer than a safe distance by a person. (CMP-1)
Informational Note: This term applies to parts that are not suita‐ bly guarded, isolated, or insulated.”

Exposed (as applied to wiring methods). Similar application apply to covers that have digital read outs can have wiring behind it that have a potential to have an electrical charge.

“On or attached to the surface or behind panels designed to allow access. (CMP-1)”

Externally Operable. Most devices have the control on them and others have them on a remote control. Much like a TV in our homes.

“Capable of being operated without exposing the operator to contact with live parts. (CMP-1)”

Feeder. On this subject feeders are what gives power from the source. When I read what the code says it is a circuit that feeds power from a service, this can be confusing because feeders can come from any source that has a over current protection device.

“All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device. (CMP-2)”

Festoon Lighting. These are the lights your wife buys from Target or Walmart for our deck or back yard and has us install them. There are a few rules to installing them and I will refer to them in future blogs.

“A string of outdoor lights that is suspended between two points. (CMP-18)”

Field Evaluation Body (FEB). That’s a mouth full. This started from the 2017 code book. Also OSHA does not see any body that can conduct an evaluations of any equipment that is not seen by a certified underwriters laboratory piece of equipment. When things get complicated and it can get complicated an accident from a worker can cause an investigation for OSHA, and OSHA will see this a violation on the owner of the equipment.

“An organization or part of an organization that performs field evaluations of electrical or other equipment. 790, 2012(CMP-1)”

Field Labeled (as applied to evaluated products). How much is this worth, I can’t tell. It depends on what state your in and how much viability the FEB has. Lighting has been know to be FEB labeled.

“Equipment or materials to which has been attached a label, symbol, or other identifying mark of an FEB indicating the equipment or materials were evaluated and found to comply with require‐ ments as described in an accompanying field evaluation report. (CMP-1)”

Fitting. Any thing that helps insure a better installation.

“An accessory such as a locknut, bushing, or other part of a wiring system that is intended primarily to perform a mechanical rather than an electrical function. (CMP-1)”

Garage. The code is very specific about the usage of space, and this is most important because of the danger of carbon monoxide.

“A building or portion of a building in which one or more self-propelled vehicles can be kept for use, sale, storage, rental, repair, exhibition, or demonstration purposes. (CMP-1)
Informational Note: For commercial garages, repair and storage, see Article 511”

Ground. Grounding has a lot to relate to this.

“The earth. (CMP-5)”

Ground Fault. These words get used by electricians to explain shorts in a feed.

“An unintentional, electrically conductive connection between an ungrounded conductor of an electrical circuit and the normally non–current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth. (CMP-5)”

Grounded (Grounding). When there is a wire between from a device or building steel to ground rod. There are other methods of grounding but that is discussed on that area.

“Connected (connecting) to ground or to a conductive body that extends the ground connection. (CMP-5)”

Grounded, Solidly. A wire from the device or building steel to earth. Sometimes this is a wire without interruption. Meaning a wire that does not have a splice or is cut to accommodate other devices or other parts of the building.

“Connected to ground without inserting any resistor or impedance device. (CMP-5)”

Grounded Conductor. The wire that connects the equipment to ground. This is seen as a green wire or screw. It can also be a bare piece of wire identifying itself as the ground.

“A system or circuit conductor that is intentionally grounded. (CMP-5)”

Ground-Fault Circuit Interrupter (GFCI). This is the breaker that sees amp between the neutral and the hot leg. And it is constantly comparing the two and it sees 6 mA or more then it opens the breaker. If it sees 6mA or more on the ground then it to opens the breaker. There is a section for this, when is comes up I will l link it to this.

“A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device. (CMP-2)
Informational Note: Class A ground-fault circuit interrupters trip when the current to ground is 6 mA or higher and do not trip when the current to ground is less than 4 mA. For further information, see UL 943, Standard for Ground-Fault Circuit Inter‐ rupters.”

Ground-Fault Current Path. This is the wire that normally does nothing 99% of it’s life. It becomes important when one day something goes wrong and that ware saves a life. Then it is the most important wire in the entire system.

“An electrically conductive path from the point of a ground fault on a wiring system through normally non–current-carrying conductors, equipment, or the earth to the electrical supply source. (CMP-5)
Informational Note: Examples of ground-fault current paths are any combination of equipment grounding conductors, metallic raceways, metallic cable sheaths, electrical equipment, and any other electrically conductive material such as metal, water, and gas piping; steel framing members; stucco mesh; metal ducting; reinforcing steel; shields of communications cables; and the earth itself.”

Ground-Fault Protection of Equipment. A power strip that is equipped to open the circuit when it sees a ground fault. People use these devices to protect TV’s, computers, refrigerators, etc….

“A system intended to provide protection of equipment from damaging line-to- ground fault currents by operating to cause a disconnecting means to open all ungrounded conductors of the faulted circuit. This protection is provided at current levels less than those required to protect conductors from damage through the operation of a supply circuit overcurrent device. (CMP-5)”

Grounding Conductor, Equipment (EGC). You will normally not see this unless you install a panel or large piece of equipment that has its own grounding equipment because it that big that it needs its own. Not just because of it mass scale but because of how delicate it’s components need to be protected.

“The conductive path(s) that provides a ground-fault current path and connects normally non–current-carrying metal parts of equipment together and to the system grounded conductor or to the grounding electrode conductor, or both. (CMP-5)
Informational Note No. 1: It is recognized that the equipment grounding conductor also performs bonding.
Informational Note No. 2: See 250.118 for a list of acceptable equipment grounding conductors.”

Grounding Electrode. This securely bring current back to earth. When installing a new service two ground rods need to be installed 6 feet apart. There is a section about this and gives specifics as to how deep the electrode needs to be.

“A conducting object through which a direct connection to earth is established. (CMP-5)”

Grounding Electrode Conductor. This is seen in services again and will be seen in that section and I will link that section to this definition.

“A conductor used to connect the system grounded conductor or the equipment to a grounding electrode or to a point on the grounding electrode system. (CMP-5)”

Guarded. When the device has an inherent opportunity to cause bodily harm, measures should be taken to protect unauthorized personnel from approaching that device. We use any type of means to protect the public from getting to a certain distance from the device.

“Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach or contact by persons or objects to a point of danger. (CMP-1)”

Guest Room. The code book does a good job at explaining what this covers.

“An accommodation combining living, sleeping, sanitary, and storage facilities within a compartment. (CMP-2)”

Guest Suite. I am going to call a good explanation here to. Other then the word “contiguous”. Why use such a complicated word that just means “not having borders”. Other then that word the anyone can understand what they are trying to say, but no, that can’t have that.

“An accommodation with two or more contiguous rooms comprising a compartment, with or without doors between such rooms, that provides living, sleeping, sanitary, and storage facilities. (CMP-2)”