Magnum Inspections Inc. Serving South Florida Since 1994 Martin County: (772) 214-9929 Broward/Palm Beach Counties: (954) 340-6615 Email me at: ev@magnuminspections.com |
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Volt - the unit of electromotive force, the measure of electrical pressure, is abbreviated v or V, and voltage is represented by I. The voltage (of a circuit) is the effective (greatest root-mean-square) difference of potential between any two conductors of the circuit concerned. Some systems, such as 3-phase 4-wire and single-phase 3-wire may have multiple circuits of differing voltages. The Nominal Voltage is the value assigned to a circuit to conveniently designate its voltage class (e.g. 120 volts, 240 volts, 480 volts). The actual voltage of the circuit can vary. Amp - or Ampere, the unit of intensity of electrical current (the measure of electrical flow), is abbreviated a or A. Watt - the unit of power or rate of work represented by a current of one ampere under a pressure of one volt (abbreviated w or W). The English horsepower is approximately equal to 846 watts. Wattage ratings of lamps actually measure the power consumption not the illuminating capability. Service - the conductors and equipment for delivering electrical energy from the supply system (e.g. the electric power utility) to the wiring system of the premises served. Ohm - the unit of electrical resistance and impedance, abbreviated with the symbol omega, W. Resistance is the opposition offered by a substance to the passage of electrical current. Impedance is the apparent resistance in a circuit to the flow of alternating current.Kilowatt-hour - Work done at the steady rate equivalent to 1000 watts in one hour. Power utility companies base their billing upon the number of kilowatt-hours (KWH) consumed. Ohm's Law - A statement of the relationship, discovered by the German scientist G. S. Ohm, between the voltage, amperage and resistance of a circuit. It states the voltage of a circuit in volts is equal to the product of the amperage in amperes and the resistance in ohms. E=IR Transformer - An apparatus for converting an alternating electrical current from a high to a low potential (voltage) or vice versa. Uses of transformers include but are not limited to the conversion of utility transmission voltage to the voltage of the premises wiring system and conversion of of voltage for use with chimes, alarm systems and low-voltage lighting. Transformers can also be used to compensate for minor variations equipment voltage requirements. Transformers only change voltage and amperage. GFCI (Ground Fault Circuit Interrupter) - A device intended for the protection of personnel that de-energizes a circuit or portion of a circuit when the current to ground exceeds a preset value. "Ground Fault" is the name applied to this undesired circuit condition. In dwelling units (e.g. houses, apartments), GFCI protection is currently required in bathrooms, garages, outdoors, unfinished basements, kitchens and wet bar sinks. Other specific installations and/or areas may also necessitate the need for protection Single Phase - a system of alternating current power where the phase relationship between ungrounded conductors is either 0 or 10 degrees. Three Phase - a system of alternating current power where the phase relationship between ungrounded conductors is either 0 or 120 degrees. NEC (National Electrical Code) - a document produced by the National Fire Protection Association for the purpose of the practical safeguarding of persons and property from hazards arising from the use of electricity. Authorities having legal jurisdiction over electrical installations adopt the code for mandatory application ( i.e. incorporate the code into law). Circuit Breaker - A device designed to open and close a circuit by non-automatic means and to open the circuit automatically on a predetermined over current without damaging itself when operated according to its rating. Fuse - An over current protective device with a circuit opening part that is heated and broken by the passage of an over current through it. Listed - Equipment and/or materials included in a list published by an organization concerned with product evaluation and production of listed items. The listing states whether the item meets designated standards or is suitable for use in a specified manner. Listing organizations acceptable to jurisdiction authorities include Underwriters' Laboratories (UL) and CSA. Accessible - Three common uses of accessible:
Labeled - Equipment or materials that a label or other identifying mark of a listing organization has been attached. Overload - Operation in excess of normal full-load rating or rated ampacity which could cause damage or dangerous overheating if continued for a sufficient time. A fault, such as a short circuit or ground fault, is not an overload. See "Over Current". Over current - Any current in excess of the rated current or ampacity. It may result from overload, short circuit or ground fault. Raceway - An enclosed channel of metallic or nonmetallic materials designed expressly for holding wires, cables, or bussbars. Examples are electrical metallic tubing (EMT), flexible metallic tubing and nonmetallic rigid conduit. Ground - A conducting connection, intentional or accidental, between an electrical circuit or equipment and the earth, or some conducting body that serves in place of the earth. Other associated terms are:
Device - A unit of an electrical system that is intended to carry but not utilize electricity.
Box - An enclosure designed to provide access to the electrical wiring system. Uses include but are not limited to provide device and lighting outlets and wiring system junction points. Specially designed boxes are required for the support of listed ceiling fans weighing less than 35 lb (15. kg). Fans exceeding this weight limit must be supported independently of the outlet box. Circuit - A complete path from the energy source through conducting bodies and back to the energy source. For example:
Conductor - a substance or body capable of transmitting electricity.
Equipment - A general term including material, fittings, devices, alliances, fixtures, apparatus , and similar items used as a part of, or in connection with, an electrical installation. Lamp - A general term for various devices for artificially producing light including commonly called items such as light bulbs and fluorescent tubes. AC and DC - Abbreviations for alternating current and direct current respectively.
Credits Many of the definitions used are based on information contained in the National Electrical Code published by the National Fire Protection Association and Webster's New World Dictionary.
Martin County: (772) 214-9929 Broward/Palm Beach Counties: (954) 340-6615 Email me at: ev@magnuminspections.com |
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