Electrical Rewiring Essay -- essays research papers

The wiring that was installed in a house many years earlier, or even as recently as a decade ago, may not be adequate for the job it is called upon to do today. A complete rewiring job is in order-or is it? Do not jump to the conclusion that every outlet must be torn out and every receptacle replaced. Many times a less expensive job will serve the purpose.   Ã‚  Ã‚  Ã‚  Ã‚  Is the wiring inadequate because you are using too many lights? Too many floor lamps? Too many radios and TVs? That is seldom the case. The wiring usually is inadequate because you have added many electrical appliances that were not considered or perhaps were not even on the market at the time of the original wiring job. The installation does not provide enough circuits to operate a wide assortment of small kitchen appliances, plus range, water heater, clothes dryer, room air conditioners and other heavy appliances. Some of these operate on 240-volt circuits, which may not be available; others operate at 120 volts but when plugged into existing circuits they overload those circuits. In addition, the service entrance equipment may be just too small for the load.   Ã‚  Ã‚  Ã‚  Ã‚  To analyze the problem of your particular house, ask yourself this: If you disconnected all the appliances, would you have all the lighting circuits you need? The answer is probably yes, which means that your rewiring job is simplified. You will still have to rewire the house, but probably not as completely as at first appeared necessary. Proceed as if you were starting with a house that had never been wired, but leave the existing lighting circuits intact. (These lighting circuits, of course, will include many receptacles used for small loads like a vacuum cleaner, radio, and TV, but not the receptacles for kitchen or laundry appliances.)   Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  There is little difference between old and new work, except that in old work there are a great many problems of carpentry. The problem is to cut an opening where a fixture is to be installed, and another where a switch is to be installed, and then to get the cable inside the wall from one opening to the other with the least amount of work and without tearing up the walls or ceilings more than necessary.   Ã‚  Ã‚  Ã‚  Ã‚  One house to be wired may be five years old, another a hundre... ...appliances. Appliances shall have no live parts normally exposed to contact other than those parts functioning as open resistance heating elements, such as the heating elements of a toaster, which are necessarely exposed. The rating of an individual branch circuit shall not be less than the marked rating of the appliance. The branch-circuit rating for an appliance that is continuously loaded, other than a motor operated appliance shall not be less than 125 percent of the marked rating, or not less than 100 percent of the market rating if the branch circuit device and its assembly are listed for continuous loading at 100 percent of its rating.   Ã‚  Ã‚  Ã‚  Ã‚  All appliances shall be protected against overcurrent. If a protective device rating is marked on an appliance, the branch circuit overcurrent device rating shall not exceed the protective device rating marked on the appliance.   Ã‚  Ã‚  Ã‚  Ã‚  A household-type appliance with surface heating elements having a maximum demand of over 60 amperes shall have its power supply subdivided into two or more circuits, each of which should be provided with overcurrent protection rated at not over 50 amperes.