MOTOR WIRING DATA From National Electrical Code 3 PHASE SQUIRREL CAGE INDUCTION MOTORS 230 Volt 460 Volt Min. # Max. Rating

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2 MOTOR WIRING DATA From National Electrical Code PHASE SQUIRREL CAGE INDUCTION MOTORS 20 Volt 0 Volt Min. # Max. Rating Min. Size Size of Full Size Wire Conduit Branch Circuit Load Wire AWG (inches) Fuses (amp) AWG hp Full Load (amp) ,000CM Size Conduit (inches) # Max. Rating of Branch Circuit Fuses SINGLE-PHASE INDUCTION MOTORS 115 Volt 20 Volt In order to avoid excessive voltage drop where long runs are involved, it may be necessary to use conductors and conduit of sizes larger than the minimum sizes listed above. # Branch-circuit fuses must be large enough to carry the starting current, hence they protect against short-circuit only. Additional protection of an approved type must be provided to protect each motor against operating overloads For full-voltage starting of normal torque, normal starting current motors. For reduced-voltage starting of normal torque, normal starting current-motors and full-voltage, starting of high-reactance, low starting current squirrel-cage motors. METHOD OF DETERMINATION OF ELECTRICAL LINE LOSS Used when meter is located an appreciable distance from the pump motor Watts equals I 2 R per line. Kilowatts or kw equals I 2 R, divided by 1,000. R equals the resistance of one line. For -phase circuit kw equals I 2 R, divided by 1,000. R equals the resistance in ohms for wire size used. I equals the full load current of the motor. Full load current of the motor should be obtained from the name plate on the motor. See tabulations at right for values of R. For more accurate determination, use the same value of R and determine I by use of an ammeter in the circuit. After determining the total kw loss, subtract this figure from the kw input to the motor. DIAMETER AND RESISTANCE OF STANDARD ANNEALED COPPER WIRE (Round Solid Conductor) (Based on U.S. Bureau of Standards) No. A.W.D Diameter Circ. Mils Resistance at 25 C (77 F) Ohms per 1,000 Feet EM-77 Page 7

3 MECHANICAL AND ELECTRICAL EQUIVALENTS FLOWING WATER 1 cubic foot per minute = 7.05 gallons per minute. 1 second foot = 1 cubic foot per second.. gallons per minute. 1 second - foot - day = 2 acre feet. WEIGHTS AND MEASURES LENGTH 1 millimeter =.097 inch. 1 mile = 1 centimeter =.97 inch. 520 feet. 1 meter = kilometers. 9.7 inches.. knots.20 feet. furlongs Circumference of a circle =.1 x diameter. AREA 1 acre = 50 square feet 1 acre foot = 50 cubic feet gallons. Area of a circle =. 1 x diam 2 VOLUME 1 barrel = 2 gallons. Volume of a sphere =.1 x diam WEIGHT 1 gram 1 cubic centimeter of distilled water. 15. grains troy..05 ounce. 1 kilogram = pounds avoirdupois. 1 metric ton 220. pounds. 1 cubic foot of concrete (1:2:) = pounds 1 cubic foot of sea water =.9 pounds. 1 cubic inch of bronze =.2 pound. 1 cubic inch of cast iron =.2 pound. 1 cubic inch of steel =.2 pound. EQUIVALENTS OF CAPACITY OR VOLUME FACTORS 1-U.S. Galon of Water U.S. Galon of Water U.S. Gallon of Water..2 1-U.S. Galon of Water.. 1-U.S. Gallon of Water Imperial Galon of Water Imperial Gallon of Water Imperial Gallon of Water Cubic Foot of Water Cubic Foot of Water Cubic Foot of Water Cubic Foot of Water Lb. of Water Lb. of Water. 1-Lb..5 1-Litre Litre Litre Litre Cubic Meter Cubic Meter Cubic Meter Cubic Meter.. 1,02 1-Cubic Meter Ton of Water (2000 lbs.) Ton of Water (2000 lbs.) Second-foot 7. 1-Second-foot.. 1-Second-foot.,272 1-Second-foot.1 0- per Minute 22 1,000,000-US. Gallons per Day ,000, ,000,000- per Day.9. 1-Acre foot.25,51 1-Inch deep on 1 sq. Mile.2,2,200 Cu. foot Lbs. at 9 F or 1.00 Sp. Gr. Imperial gallon Litres Lbs. at 9 F or 1.00 Sp. Gr. Lbs. at 9 F Litres Cubic meter U.S. Gallon Kilogram U.S. Gallon Imperial Gallon Cu. foot Imperial Gallons Cu. yards Cu. feet at 9 F Imperial Gallons at 9 F per Second U.S Gallons per Minute per Day Acre inch per hour approximately Second-fool Second-feet Acre feet Gallons per Minute Gallons Cu. ft. Boiler HP x.072 TEMPERATURE Degrees C = 5 x (F - 2) Degrees F= 9 x C PRESSURE 1 atmosphere = 70 millimeters of mercury at 2 F..7 pounds per square inch inches of mercury at 2 t. 211 pounds per square foot. 1.0 kilograms per square centimeter..97 feet of water at 2 F.. meters of water at 20 C bar. 1 foot of air at 2 F and barometer =.071 pound per square foot..0 inch of water at 2 F. 1 foot of water at 2 F =. pound per square inch 2.55 pounds per square foot.. inch of mercury at 2 F feet of air at 2 F and barometer inch of water 2 F =.01 pound per square inch pounds per square foot.577 ounce per square inch.07 5 inch of mercury at 2 F. feet of air at 2 F and barometer pound per square inch = inches of mercury at 2 F 2.01 inches of mercury at 2 F feet of water at 2 F kilograms per square centimeter.00 atmosphere millimeters of mercury at 2 F. MECHANICAL AND ELECTRICAL UNITS 1 btu = 5 joules foot pounds. 7.5 kilogram-meters horsepower hour. 1 foot pound = 1.55 joules..12 kilogram-meter..00 btu..021 gram calorie horsepower hour. 1 horsepower = 75.7 watts..7 Kw (metric),000 foot pounds per minute. 1,700 gram calories per hour. 27,7 kilogram-meters per hour. 2,57 btu per hour. 75 kg m/s 1 joule = 1 Nm.197 kilogram-meter..775 foot pound..29 gram calorie btu. 1 kilogram-meter = 7.2 foot pounds. 9.0 joules. 2. gram calories..009 btu. 1 kilowatt = 00 watts. 1.1 horsepower. 2,55,200 foot pounds per hour. 0,500 gram calories per hour. 7,000 kilogram-meters per hour.,15 btu per hour..2 boiler horsepower. EM-77 Page

4 METRICATION LENGTH 1 km = 00 m 1 m = 00mm = 0 cm cm = 0.97 in in = 2.5 cm = 25. mm m =.2 ft ft = 0.0 m m = 1.09 yd yd = 0.9 mm km = 0.21mi mi = 1.1 km CAPACITY 1L = 00 cc 1L = 00 ml 1L = 0.05 ft cu ft = 2.2 L 1L = 0.22 gal (U.S.) gal =.75 L 1L = 1.02 in cu in = 0.01 AREA sq cm sq m sq m ha sq km = sq in =.7 sq ft = 1.19 sq yd = 2.7 acres = 0. sq mi sq in sq ft sq yd acre sq mi =.5 sq cm =.0929 sq m =. sq m =.05 ha = 259 sq km PRESSURE 1 kg per sq cm =.22 psi 1 kg per cm 2 =.97 std atm 1 kg per cm 2 =.9l bar 1 psi =.070l kg per cm 2 1 kg per m 2 =.202 lbs/ft 2 1 lb per ft 2 =.2 kg per m 2 1 std atm = kg per cm 2 1 metric atm = kg per cm 2 1 st atm =.959 psi 1 N/m 2 = x - kg/cm 2 CENTIGRADE/FAHRENHEIT CONVERSION FORMULAE F = 9/5 x + 2 = 1. (C + 17.) C=5/9(F 2) WEIGHT one kg = 00 g g = 15.2 grains g =.05 oz kg = 2.20 lbs. kg =.0011 ton (short) metric ton = 1.25 ton (short) grain =.0 g VOLUME one cu m = (0) cm cu cm =.01 cu in cu m = 5.15 cu ft cu m = 1.0 cu yd one g = 00 mg oz = 2.5 g lb =.5 kg ton (short) = kg ton (short) =.907 metric ton (short) = 2000 lbs one L = 00 cc = 00 ml cu in = 1. cm cu ft =.02 m cu yd =.75 m CONVERSION CONVERT FROM gal (U.S.) per min m ft hp (mech.) hp (metric) kg/cm 2 psi TO ft m U.S. gpm L/sec hp (metric) hp (mech.) psi kg/cm 2 MULTIPLY BY HORSEPOWER* FORMULAE 1 hp =,000 ft lb/min bhp =.70 kw bhp = Q (gpm) x H (ft) x Sp. Gr. = 550 ft lb/sec. 90 x E 1 hp =.755 kw (metric) = x H (m) x Sp. Gr. = 75 kg/m/sec x E mhp =.9 x bhp = x H (m) x Sp. Gr ABBREVIATIONS acre-spell out atm-atmosphere bar-spell out bhp-brake horsepower C- Centigrade (Celsius) cc-cm cm-centimeter cu-cubic F-Fahrenheit ft-foot g-gram gal-gallon gpm-gal per min grain-spell out ha-hectare hp-horsepower in-inch km-kilometer kpa-kilopascal L-liter lb-pound m-meter m -cubic meters metric-spell out mhp-metric horsepower mi-mile mm-millimeter N-Newton oz-ounce P-Pascal psi-pounds per square inch Sp. Gr.-Specific Gravity ton-spell out yd-yard EM-77 Page 9

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