Low-voltage switching systems
Light fixtures are normally controlled by switches that interrupt the electrical flow in a 110-volt circuit. However, in some houses, the light switches operate at about 24 volts. This type of wiring is generally installed so that the lights can be controlled from three or more locations. With this system, it is possible to control all the lights in the house from a master panel located anywhere in the house. The circuit for a low-voltage system includes a transformer and an electrically operated switch (relay) that is usually mounted near the fixture. If your house has this type of system, make sure that there are replacement relays. Many electrical-supply houses do not stock these relays, and they would have to be specially ordered from the supplier. If you do not have replacement relays and a relay breaks down, you might be without light from that fixture for several weeks before the condition can be repaired.
Electrical violations should concern the home buyer-owner because they represent potential safety or fire hazards. As you walk around the interior and exterior of the structure, keep in mind those items that are considered common electrical violations. If there is an outside pole lamp, are the wires leading to the lamp buried? They should be. If a portion of the wire is exposed, is it stamped UF-Sunlight Resistant? This indicates that it can be used as exterior wire. Many times, homeowners unknowingly use interior-type wire as exterior wire. This is quite dangerous because sun, rain, or soil conditions can cause the insulation covering the wire to deteriorate, exposing the conductors. Incidentally, if there is an outside pole lamp, it should be turned on to see whether it is operational. If it is not, the problem may be as simple to correct as changing the bulb or replacing the switch. However, there might be faulty underground wiring. Do all of the outside electrical outlets have exterior-type covers that provide protection against water penetration? Although not a retroactive requirement, it is recommended that all outside lights and outlets be protected with ground-fault interrupters.
Inside the house, particularly in the basement, look for open junction boxes, loose wires, and exposed wiring and splices (unless the wires are low voltage). Recently, an inspection of a four-story multifamily brownstone walkup in New York City revealed several violations in one circuit located in the basement. The wire coming from the panel box was rated at 15 amps, but it was protected in the panel box by a 30-amp fuse. The wire was hanging in loops from the basement ceiling and had open splices with exposed conductors (splices in a branch circuit should be contained in a closed junction box). One of the hanging loops with exposed conductors was resting on the inlet water pipe leading to the heating-system boiler, and the floor below the pipe was wet. You seldom run into a more dangerous condition. Yet there were ten families living in that house.
If the wiring looks makeshift or appears to have been modified by a nonprofessional, you should request that the seller provide you at contract closing with the Board of Fire Underwriters’ certificate of approval for the electrical wiring currently in the house. In your area, the Board of Fire Underwriters might be called by a different name, or a private commercial service might be used.
Finally, when walking through the house, see if all of the receptacle outlets and switches have cover plates. They should. Also, when using an extension cord, the homeowner sometimes runs the cord through the inside of a partition wall. This is a violation of the electrical code. If an outlet is needed, a permanent one should be installed.