What is a GFCI?
A GFCI is a fast-acting circuit breaker that senses small imbalances in the circuit caused by current leakage to the ground, and in a fraction of a second (25 milliseconds), shuts off the electricity. The GFCI continually matches the amount of current going to the electrical device (from the line side), against the amount of returning current from the device along the electrical (load side) path. Whenever the amount of current "going" differs from the amount of current "returning" by approximately 5 milliamps, the GFCI interrupts the electric power within as little as 1/40 of a second. The GFCI, however, does not protect people from line-to-line contact hazards - such as a worker holding the two "hot" wires or a "hot" and "neutral" wire in each hand. The GFCI protects against the most common form of electrical shock hazard - ground fault, it also protects against fires, overheating and destruction of insulation on wiring. GFCIs can be used successfully to reduce electrical hazards on construction sites. Tripping of a GFCI (interrupting the current flow) is sometimes caused by wet connectors and tools. It is a good practice to limit exposure of connectors and tools to excessive moisture by using water tight or sealable connectors. Providing more GFCIs or shorter circuits, can prevent tripping caused by the cumulative leakage from several tools or by leakage from extremely long circuits. (See editorial note below.)
*Source: OSHA Publication 3007, 1998 revised.
Manufacturers of portable GFCI cord sets only offer sets up to 100 feet in length. Beyond 100 feet of cord, the current can decease causing the GFCI to misinterpret the current decrease as a ground fault condition and shut off the electrical power.
People protection = GFCI
Equipment protection = Surge Protector
Tip: Electrical Safety for the Office, Workplace or Home
GFCI wall receptacles in the kitchen, bathroom, cafeteria or office area may not provide all the electrical protection you need. Test these outlets every month.
- OSHA compliant; portable; use indoors or outdoors; use with power tools and equipment
- 20 amp relay for greater electrical capacity and use with higher amperage power tools
Industrial & construction