75 HP = 55 KW
55 = 31/2 x 0.220 x I x cos φ = 31/2 x 0.220 x 0.8 x I
I = 55/(31/2 x 0.220 x 0.8) = 180,42 A
3 x 70 mm2 is the size of cable for 75 HP 220 Volts 3 phase motor
Have to know what voltage the motor is connected to.
70 mm2 per line, for 134 A and 400V.
Answer for USA, Canada and countries running a 60 Hz supply service.
The formula for amperage when horsepower is shown is,
I = HP x 746/1.73 x E x %Eff. x pf = 75000/1.73 x 400 x .90 x .90 = 75000/561 = 133 amps.
Motor cables have to be rated at 125% of the motors full load amps. 133 x 125% = 166 amps.
A # 2/0 copper wire with an insulation factor of 75 or 90 degrees C is rated at 175 and 185 amps respectively.
If the motor is over a large distance from the supply distribution go to a 3/0 conductor which is one size larger. This will overcome any voltage drop that may occur.
The size of the wire would depend on the current drawn, and that depends on the voltage it is designed to work at. A motor that size could be 415 v or a higher voltage.
A 75 kW motor would need a 100 kVA supply and at 415 v that would be 140 amps, requiring a wire size of #0 or 50 mm2 cross section.
At a higher voltage the current would be less and the wire size would be smaller. At 11 kV the current would be only 5.3 amps, requiring wire of only 1.0 mm2 cross-section.
No . . . that is because you did not specify the voltage.
The cable size feeding 75hp-3phase motor is 16mm square in measurement.
150x4
240mm sq
380
First of all find out what voltage the motor is designed to work on.
you need the current of motor or the KW/HP rating
The cable size depends on a few factors, such as the supply voltage, the method of starting the motor, (direct-on-line, or star delta) and the length of cable required to compensate for voltage drop. Also, if the cable is copper or aluminum.110 kW motor has a rated current of 200 amps at 415 volts, so the correct copper cable size would have a cross-sectional area of 75 square mm., if the motor is started direct-on-line.At 660 volts, the rated current would be 118 volts and the cable size would be 35 square mm.
Yes, most large motors are three phase. Usually single phase motors only go up to 10 HP. Larger than this and the wire size and contactors used to control the motors becomes extreme. For example a single phase 10 HP motor on 115 volts draws 100 amps. The same single phase motor on 230 volts draws 50 amps. The same 10 HP motor on three phase system draws the following amperage; 230 volts is a 28 amp draw, 460 volts is a 14 amp draw and 575 volts is a 11 amp draw. As you can see the higher the voltage becomes, the smaller the wire feeder size is needed and much smaller size contactor can be used to control the motor.
Assuming it is a 400 V three-phase motor, the phase current is 11 amps, or more if the power factor is less than 1.0 (or the supply voltage is different). If it is a 400 V motor the cable should be capable of carrying 16 amps, so a 2.5 mm-sq 4-core cable is needed.
Sir, what is the cable size for 1.5kw 3phase induction motor 400v?
First of all find out what voltage the motor is designed to work on.
you need the current of motor or the KW/HP rating
The supply is probably 400 v three-phase with 230 v between each live and neutral. On this assumption the current is 49 amps and the copper cable size is 16 mm2 for a run of up to 30 metres.
Yes, most large motors are three phase. Usually single phase motors only go up to 10 HP. Larger than this and the wire size and contactors used to control the motors becomes extreme. For example a single phase 10 HP motor on 115 volts draws 100 amps. The same single phase motor on 230 volts draws 50 amps. The same 10 HP motor on three phase system draws the following amperage; 230 volts is a 28 amp draw, 460 volts is a 14 amp draw and 575 volts is a 11 amp draw. As you can see the higher the voltage becomes, the smaller the wire feeder size is needed and much smaller size contactor can be used to control the motor.
The cable size depends on a few factors, such as the supply voltage, the method of starting the motor, (direct-on-line, or star delta) and the length of cable required to compensate for voltage drop. Also, if the cable is copper or aluminum.110 kW motor has a rated current of 200 amps at 415 volts, so the correct copper cable size would have a cross-sectional area of 75 square mm., if the motor is started direct-on-line.At 660 volts, the rated current would be 118 volts and the cable size would be 35 square mm.
Assuming it is a 400 V three-phase motor, the phase current is 11 amps, or more if the power factor is less than 1.0 (or the supply voltage is different). If it is a 400 V motor the cable should be capable of carrying 16 amps, so a 2.5 mm-sq 4-core cable is needed.
If it's a 380 v 3-phase supply, the current is up to 300 amps which could be supplied over a short distance by XLPE cable with 70 sq. mm cross-section conductors.
i have 200 hp motor what i need cable size in 100 feet distance
3 core 35 sq mm alu. Or 3 core 25 sq mm cup.
I would go with 20 amp 3 pole 15 amp will also do
Wire sizing is determined by the amount of amperage that the connected device draws. Look on the nameplate of the motor and state the amperage. Then the question can be answered.