We've tried to compile a list of common electrical questions & their answers. Should you have a question that you'd like answered you may call us any time. Our master electrician, Jack Gavin will be glad to help!
What is a GFCI?
A ground fault circuit interrupter or GFCI, is an electronic device for protecting people from serious injury due to electric shock.
How does the GFCI work?
GFCI's constantly monitor electricity flowing in a circuit. If the electricity flowing into the circuit differs by even a slight amount from that returning, the GFCI will quickly shut off the current flowing through that circuit. The advantage of using GFCI's is that they can detect even small variations in the amount of leakage current, even amounts too small to activate a fuse or circuit breaker. GFCI's work quickly, so they can help protect consumers from severe electric shocks and electrocution.
If an appliance continues to blow a fuse or trip a circuit breakers, what should I do?
Appliances that repeatedly blow fuses or trip circuit breakers should be unplugged and repaired or replaced. In addition, appliances that shock you should also be unplugged and repaired or replaced.
What is the purpose of the National Electrical Safety Code® (NESC®)?
The purpose of the NESC is the practical safeguarding of persons during the installation, operation, or maintenance of electric supply and communication lines and associated equipment. The NESC contains the basic provisions that are considered necessary for the safety of employees and the public under the specified conditions. The NESC is not intended as a design specification or as an instruction manual.
What does an electrical service look like?
There are logically four wires involved with supplying the main panel with power. Three of them will come from the utility pole, and a fourth (bare) wire comes from elsewhere. The bare wire is connected to one or more long metal bars pounded into the ground, or to a wire buried in the foundation, or sometimes to the water supply pipe (has to be metal, continuous to where the main water pipe entering the house. Learn more about what an electrical service looks like.
What's the difference between "grounding" and "grounded" and "neutral".
According to the terminology in the CEC and NEC, the "grounding" conductor is for the safety ground, i.e., the green or bare or green with a yellow stripe wire. The word "neutral" is reserved for the white when you have a circuit with more than one "hot" wire. Since the white wire is connected to neutral and the grounding conductor inside the panel, the proper term is "grounded conductor". However, the potential confusion between "grounded conductor" and "grounding conductor" can lead to potentially lethal mistakes - you should never use the bare wire as a "grounded conductor" or white wire as the "grounding conductor", even though they are connected together in the panel. [But not in sub panels - sub panels are fed neutral and ground separately from the main panel. Usually.] Note: do not tape, colour or substitute other colour wires for the safety grounding conductor. In the trade, and in common usage, the word "neutral" is used for "grounded conductor". This FAQ uses "neutral" simply to avoid potential confusion. We recommend that you use "neutral" too. Thus the white wire is always (except in some light switch applications) neutral. Not ground.
What size wire should I use?
For a 20 amp circuit, use 12 gauge wire. For a 15 amp circuit, you can use 14 gauge wire (in most locales). For a long run, though, you should use the next larger size wire, to avoid voltage drops. 12 gauge is only slightly more expensive than 14 gauge, though it's stiffer and harder to work with. Here's a quick table for normal situations. Go up a size for more than 100 foot runs, when the cable is in conduit, or ganged with other wires in a place where they can't dissipate heat easily: Gauge Amps 14 15 12 20 10 30 8 40 6 65 We don't list bigger sizes because it starts getting very dependent on the application and precise wire type.
Can I install a replacement light fixture?
In general, one can replace fixtures freely, subject to a few caveats. First, of course, one should check the amperage rating of the circuit. If your heart is set on installing half a dozen 500 watt floodlights, you may need to run a new wire back to the panel box. But there are some more subtle constraints as well. For example, older house wiring doesn't have high-temperature insulation. The excess heat generated by a ceiling-mounted lamp can and will cause the insulation to deteriorate and crack, with obvious bad results. Learn more about light replacement.
My house has aluminum wiring, is it dangerous?
Aluminum wiring During the 1970's, aluminum (instead of copper) wiring became quite popular and was extensively used. Since that time, aluminum wiring has been implicated in a number of house fires, and most jurisdictions no longer permit it in new installations. We recommend, even if you're allowed to, that do not use it for new wiring. But don't panic if your house has aluminum wiring. Aluminum wiring, when properly installed, can be just as safe as copper. Aluminum wiring is, however, very unforgiving of improper installation. Learn more about aluminum wiring.