ELECTRIFICATION - Residential Electrical Distribution System in the Farm

Type a (15A/125V)
Type b (15A/125V)
Type C (2.5A/250V)
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Terms in this set (31)
APPLIANCE (2-wire circuit)Supply energy to 1 or more appliance outlets.General purpose (2-wire circuit)• Supply energy to 2 or more receptacles or outlets for lighting and appliancesMultiwireSupply energy through 2 or more ungrounded conductors and a grounded conductor.Individual (2 or 3 wire circuit)• Supply energy to one utilization equipmentRULE OF BRANCH CIRCUITThe ampacity of branch-circuit conductors should not be less than the load. Also, the circuit wires must be able to handle the load of the branch circuit.RULE OF BRANCH CIRCUITAttaching wires that are too small for the circuit amperage poses a definite danger of fireBRANCH CIRCUIT AMPERAGEBranch circuit must be 120-volt circuits which feed all the standard outlets and lighting circuits 120-Volt circuit can support up to 15-20 ampsBRANCH CIRCUIT AMPERAGEbranch circuit must be 240-volt circuits which feed circuits that feed major appliances, such as an electric clothes dryer, an electric range, and central air conditioning units •240-Volt circuit can support up to 30, 40, or 50 ampsWire Gaugea measurement of wire diameter. This determines the amount of electric current the wire can safely carry15-amps: 14-gauge copper wire 20-amps: 12-gauge copper wire 30-amps: 10-gauge copper wire 45-amps: 8-gauge copper wire 60-amps: 6-gauge copper wire 80-amps: 4-gauge copper wire 100-amps: 2-gauge copper wireratings of individual wire gaugesSERVICE ENTRANCEwhere the wires connected to the load side of the meter enter the house or building.SERVICE ENTRANCEin a residence is commonly thought of as a breaker or fuse box.SERVICE ENTRANCEIn larger more complicated commercial or industrial electrical systems, the service entrance may be a main disconnect panel or a trough where up to six main switches are present.SERVICE DROPAn overhead power connection from the utility lines to the service entrance is called the Service Drop.SERVICE DROPhas two 120V lines and a neutral conductor. The three lines may be independent conductors or housed in a three conductor cable called a triplex cable.SERVICE DROPThe three conductors comprising the service drop consist of two hotlines and one neutral. Each hotline as a potential of 120V to the neutral line. Between the two hotlines, there is a difference of potential 240V. This is why the service is identified as a 120/240V service.OVERHEAD SERVICE DROP CONDUCTORS•The conductors shall not be smaller than 8.0 mm2 (3.2 mm dia.) copper or 14 mm2 aluminum or copper-clad aluminum.SERVICE LATERALthe primary power lines pass through the conduit to the pad transformer input. The secondary power lines connect the transformer output to the electrical service meter.SERVICE LATERALTransformers are devices that are used to raise or lower a voltage level. In this case, the transformer is used to lower the voltage from the utility to the 120/240V residential level.UNDERGROUND SERVICE LATERAL CONDUCTORS•The conductors shall not be smaller than 8.0 mm2 (3.2 mm dia.) copper or 14 mm2 aluminum or copper-clad aluminum.GROUNDED CONDUCTORSshall not be less than the minimum size as required by which is the Grounded Conductor Brought to Service Equipment.