CH 6 GFCI, AFCI, SPD, IDCI, and ALCI Protection

What does a GFCI do?

It monitors the current balance between the ungrounded "hot" conductor and the grounded conductor. As soon as the current flowing through the "hot" conductor is in the range of 4 to 6 mil- liamperes more than the current flowing in the "re- turn" grounded conductor, the GFCI senses this unbalance and trips (opens) the circuit off.

Does a GFCI provide overload protection?

It provides ground-fault protection only

Does a GFCI sense a solid short circuit (2 hot conductors or between hot and grounded)?

No, the branch-circuit fuse or circuit breaker provides this protection

Does a GFCI protect against electrical shock?

Not when touching both circuit conductors (2 hot wires or 1 hot and 1 grounded) since the current flowing in both conductors is the same. It also takes 25 milliamperes for the GFCI to trip.

What is the distance from the sink that GFCI protection is required?

Within 6ft of the top, inside edge of the bowl of the sink without piercing a floor, wall, ceiling, or fixed barrier, or passing through a door, doorway or window

Can you use AFCI and GFCI devices in series?

Yes, the protection is complementary

210.8(A) requires ground-fault circuit interrupter (GFCI) protection for single-phase, 125-volt, 15- and 20-ampere receptacles in what locations?

Bathroom Garage (attached and detached) Outdoors Crawl spaces at or below grade Unfinished basements Kitchens (All receptacles that serve the countertop surfaces, including islands and peninsulas) Sinks Boathouses Bathtub and shower stalls Laundry areas Kitchen dishwasher branch circuit Swimming pools, hot tubs, spas For the branch circuit supplying heated floors in bathrooms, kitchens, and in hydromassage bathtub locations

When replacing existing receptacles, GFCI, AFCI tamper resistant, and weather resistant are required

True, NEC 406.4(D)

Define series arc

When a conductor that is carrying current breaks or when a loose connection oc- curs, a "series" arcing fault is created. The cur- rent draw of the connected load is trying to jump across the opening created by the break or loose connection.

Define parallel arc

When arcing occurs between the black ("hot") and white grounded (neu- tral) circuit conductors, or between the black ("hot") conductor and ground, it is referred to as a "parallel" arc.

When do Class A GFCI devices trip?

When current to ground is 6 milliamperes or greater

What distance is GFCI protection required from bathtub and shower stalls?

Within 6 feet (1.8 m) of the outside edge of the bathtub or shower stall

Types of AFCI Devices

1. Combination AFCI - installed in the panel where the branch circuit originates. Protects both branch/feeder AFCIs and outlet AFCIs 2. Branch/feeder AFCI - installed in the panel board and protects the branch-circuit wiring 3. OutletAFCI - an AFCI receptacle that protects cord sets that are plugged in 4. Portable AFCI - this is a plug-in device with one or more receptacles. It provides protection for cords that are plugged to it 5. CordAFCI - a plug-in device that protects the power cord connected to it. It has no additional outlets.

Where are tamper resistant receptacles exempt in dwelling units?

1. Located 5 1/2 feet above the floor 2. receptacles part of a luminaire or appliance 3. A single receptacle or a duplex receptacle for two appliances located within dedicated space for each appliance that in normal use is not easily moved from one place to another 4. Nongrounding receptacles used for replacements

Two types of voltage transients

1. Ring wave 2. Impulse

Types of arcs

1. Series arcs 2. Parallel arcs

Arc-Fault Circuit Interrupter (AFCI)

A device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and by functioning to de-energize the circuit when an arc fault is detected

What Is an Outlet?

A point on the wiring system at which current is taken to supply utilization equipment. They include: lighting outlets, receptacle outlets, ceiling (paddle) fan outlets, and outlets for single station from fire alarms.

When is GFCI protection exempt when in basements?

A receptacle that serves a permanently installed fire or burglar alarm system

What is a device?

A unit of an electrical system, other than a conductor, that carries or controls electric energy as its principal function. They include light switches, occupancy sensors, timers, and receptacles.

Where are weather resistant receptacles required?

All 15- and 20-ampere, 125- and 250-volt nonlocking type receptacles installed in a damp or wet location are required to be listed weather-resistant type

Which is more sensitive - branch/feeder AFCI or outlet AFCI?

An outlet AFCI is more sensitive

What is arcing?

Arcing is current flowing outside of the intended path. Arcing is a function of voltage and the amount of current flowing in the arc.

What is an impulse transient?

These transients originate outside of the building and are caused by utility company switching, lightning, and so on

What is ring wave transient?

These transients originate within the building and can be caused by copiers, com- puters, printers, HVAC cycling, spark igniters on furnaces, water heaters, dryers, gas ranges, ovens, motors, and other inductive loads

When is GFCI protection exempt when outdoors?

They're not required for a receptacle not readily accessible and supplied by a dedicated branch circuit for snow melting or deicing equipment.