The electrical code states that a 50 HP 460 volt three phase motor draws 65 amps. The ideal amperage would be taken from the motors nameplate as different motors of the same horsepower will have different amperage's depending on what they are designed to do.
Wire is sized by the load amperage. The formula for amperage when the HP is known is I = HP x 746/1.73 x E X %eff x pf. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. I = 60 x 746 = 44760/ 1.73 x 480 x .89 x .89 = 44760/658 = 68 amps. Motor feeders have to be sized to 125% of the motors full load amps. 68 x 125% = 85 amps A #3 copper conductor will limit the voltage drop to3% or less when supplying 85 amps for 220 feet on a 480 volt system.
A 15 amp should be fine, provided that #14 wire is used for the outlet. If #12 is used, then use a 20 amp breaker. Depending on what the motor voltage is makes a difference on what the wire size is. A 3/4 HP motor draws 13.8 amps at 115 volts and 6.9 amps at 230 volts. The motor feeder conductor must have an ampacity at least equal to 125% of the full load current rating of the motor. 13.8 x 125% = 17.25 amps. The conductor required on a motor using 120 volts is #12 rated at 20 amps. The breaker for this motor needs to be rated at 30 amps.
To answer this question, wire size is rated in the amount of amperage that it can legally carry. The formula to find amperage when the HP is known is I = HP x 746/1.73 x E x %eff x pf. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. Amps = 10 x 746 = 7460 = 7460/1.73 x 220 x .84 x .86 = 7460/275 = 27.1 amps. The electrical code states that a motor conductor has to be rated at 125% of the motors full load amperage. 27.1 x 125% = 33.8 A #8 copper conductor with an insulation factor of 60, 75 or 90 degrees C is rated at 40, 50 and 55 amps respectively.
i have 200 hp motor what i need cable size in 100 feet distance
what is the full load amps for 2.4 hp motor at 460 volts ?
At 600 volts the rule of thumb is one amp per horsepower. So a 20 HP motor would need 20 amp wire. The code book states that a 20 HP motor at 575 volts draws 22 amps. The conductor for a motor has to be 125% rating of the motors FLA (full load amps). 22 x 125% = 27.5 amps. A #10 copper conductor with a insulation factor of 60,75 or 90 degrees C is rated at 30 amps.
The electrical code states that a 50 HP 460 volt three phase motor draws 65 amps. The ideal amperage would be taken from the motors nameplate as different motors of the same horsepower will have different amperage's depending on what they are designed to do.
The electrical code states that a 30 HP induction motor at 460 volts three phase will draw 40 amps. <<>> I = 33.34 AMPS IF EFF.= 95% AND P.F.= 85%
A three phase 30 HP at 240 volts draws 80 amps. Motor feeders have to be rated at 125% of the motors full load amps. 80 x 125% = 100 amps. A # 3 copper conductor with an insulation factor of 75 or 90 degrees C are rated at 100 and 105 amps respectively. Non-time delay fusing is 225 amps, time delay fusing is 125 amps and a circuit breaker is sized by 250% x 80, the full load amps, which equals 200 amps.
The electrical code states that a 7.5 HP 460 volt three phase motor draws 11 amps. For fuse sizes, non time delay - 30 amps, time delay type D - 20 amps and if using a breaker it will be 30 amps. Minimum wire size is #12 and the maximum setting of overload devices will be 13.75 amps
Breakers are sized by the conductors that are connected to them. Conductors are sized by the amperage that the load draws. The electrical code states that a 50 HP 460 volt three phase motor draws 65 amps. The ideal amperage would be taken from the motors nameplate as different motors of the same horsepower will have different amperage's depending on what they are designed to do. The feeders for this motor have to be sized at 125% of the motors full load amperage. 65 x 125% = 81 amps. A #4 copper conductor with and insulation rating of 75 or 90 degrees C is rated at 85 amps. The breaker for this motor is 150 amp or 175 amp fusing or 110 amp time delay fusing.
T430.247 of the NEC shows that a 1 hp motor operating at full load on 115v will draw 16 amps, called Full Load Current (FLC). Conductors supplying this motor are required to be 125% of FLC which is 20 amps. Motor circuits are complicated things and do not follow the rules of other circuits. This motor, while drawing a maximum of 16 amps at full load and supplied with #12 AWG copper conductors can be protected by a breaker of 40 amps.
The formula you are looking for is I = kW x 1000/1.73 x E x pf. I = 1.5 x 1000 = 1500. 1500/1.73 x 400 x .86 = 1500/595 = 2.5 amps. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. A feeder for a motor has to be rated at 125% of the motors full load amps 2.5 x 125% = 3.1 amps A #14 copper conductor with an insulation rating of 90 degrees C is rated at 15 amps.
A single phase 10 HP motor will draw aproximately 50 amps. A three phase 10 HP motor will draw aproximately 28 amps.
750 watts per horse power20 x 750 = 15,000 watts / 220V = 68A68 amps at 220 volts
Wire is sized by the load amperage. The formula for amperage when the HP is known is I = HP x 746/1.73 x E X %eff x pf. A standard motor's efficiency between 5 to 100 HP is .84 to .91. A standard motor's power factor between 10 to 100 HP is .86 to .92. I = 60 x 746 = 44760/ 1.73 x 480 x .89 x .89 = 44760/658 = 68 amps. Motor feeders have to be sized to 125% of the motors full load amps. 68 x 125% = 85 amps A #3 copper conductor will limit the voltage drop to3% or less when supplying 85 amps for 220 feet on a 480 volt system.