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At 440 volts, a 40 hp motor pulls about 68 amperes. Well, sort of...
The definition of a horsepower for an electric motor is 746 watts. Multiply 746 by 40, and divide by 440, and you do get 68 amperes.
1hp=746W
hence, 40hp=29840W
given that the motor draws 440volts
but current = power/voltage.
therefore, current=29840/440 = 67.81818182 amps.
The complexity, however, is that a motor is an inductive load and it has reactance. This reactance will change the phase angle between voltage and current, causing current to lag voltage by some amount. Power factor is a measure of the ratio of apparent power to true power, and is essentially the cosine of the phase angle between voltage and current. This power factor will make the true power be higher than the apparent power, but horsepower is based on apparent power.
Bottom line is that the amperes in this case will be dependent on the power factor, perhaps about 75 amperes, maybe.
Also, such a motor is bound to be a three phase motor. The amperes will be spread out among the three phases so, for 68 amperes, it would be about 23 amperes per phase, and for 75 amperes, it would be about 25 amperes per phase.
In terms of power factor, it might be closer to unity than anticipated, if the motor has power factor correction capacitors installed.
Keep in mind that starting current will be much higher than running current. Also note that large motors of this type would typically be started in wye configuration, so as to present lower voltage across the windings, and then run in delta configuration, for full power operation.
I'm going to stick with about 25 amperes per phase, full power run mode, unless someone else has something to add, of course.
CommentAn added complication is that '40 hp' refers to the output power of the motor. Unless you know the efficiency, you cannot work out the input power. Incidentally, 68 A single phase doesn't work out at 25 A per line for a 3-phase motor!!!!! It works out a little over 39 Aper line, because P = (root 3) x U x I x power factor!
What else can I help you with?
Will a 370 VAC motor run using a 440 VAC capacitor?
If the motor is rated at 370 v and the supply is 370 v, the capacitor needs to be rated at 370 or more volts, so a 440 v capacitor will be OK.
What is the cable size for motor 15kw 440 volts connection?
The current draw is about 27 amps. A motor feeder has to be 125% of the motors full load amperage. 27 x 125% = 33 amps. A #8 copper conductor with an insulation factor of 90 degrees C is rated at 40 amps.
Why 440 volts running capacitor if my ac is 230 volts?
The 440 volts listed on the cap is the maximum allowable voltage the capacitor can handle. You could actually use a 370 volt cap on 230 volts. ANSWER; 230 volts AC can it actually be 644 volts peak to peak . It is 44ov because it must be rectified and sees only 324 volt peak which is withing the 440 volt capacitor handling voltage
Can you connect 460Vac motor to 480Vac circuit?
Yes, the 440 volt motor is withing the 10% voltage range of the 460 volt group. When the supply is said to be 480 volts, usually it is lower than what it is stated to be. Once the motor is connected check the current against the motor's nameplate amperage.
Can 3 phase 380 volts 50 hz motor run on 440 volts 50 hz supply?
No, the voltage gap between the two voltages is too large.
Can a 220 volt motor run on 440 volts?
No it will fry the motor use a voltege reducer
Can a 240 Volts delta motor run on 440 Volts star connection?
If it is a 240 v delta motor it needs a 240 v three-phase supply, which has 139 v between line and neutral, so 440 v would not be acceptable.
How many watts equal one amp at 440 volts?
Watts = Amps x Volts x Power Factor Power factor varies from 0 to 1 with 1 being a pure resistive load like a light bulb. A motor would have a lesser value. So if your load is resistive just use 1 x 440.
A circuit whose resistance is 22 ohms and has an applied voltage of 440 volts will draw a current of?
20A By using V=IR
Will a 370 VAC motor run using a 440 VAC capacitor?
If the motor is rated at 370 v and the supply is 370 v, the capacitor needs to be rated at 370 or more volts, so a 440 v capacitor will be OK.
Can a 440 volt motor run on 460 volts?
Yes it can. Motors can usually tolerate a 10% fluctuation in supply, so an increase of 20 volts wont do any harm in this case - it's less than a 5% increase.
What is the cable size for motor 15kw 440 volts connection?
The current draw is about 27 amps. A motor feeder has to be 125% of the motors full load amperage. 27 x 125% = 33 amps. A #8 copper conductor with an insulation factor of 90 degrees C is rated at 40 amps.
How to convert 440 VOLTS to 380 VOLTS?
You can use a transformer to step down the voltage from 440 volts to 380 volts. Make sure to use a transformer that is rated for the required input and output voltage, and have a qualified electrician perform the installation for safety.
In 3 horsepower how many amps needed?
3 amps on 120 volts is almost 1/2 hp. To be exact 0.48 hp, that's why I said almost 0.5 hp or 1/2 hp. So say you are thinking of buying a 3 amp grinder or table top sander and you want to know about how many HP (Horse Power) it is, the answer is 120 volts X 3 amps = 360 X 0.00134 = 0.4824 HP which is almost a 1/2 HP you can do the math from there if its a 6 amp motor then its almost a 1 HP motor or to be exact 0.4824 X 2 = 0.9648 also almost 1 HP. This is if you are on 120 volts. If you are on 110 or 125 volts its about the same.
12 HP Century Electric MotorModel CSH-81-B. Serial ac Code L RPM 1750Spec-9568 it is one half hp not 12.?
A 1 hp electric motor draws ABOUT 746 watts. Multiply volts times amps to get watts. a 1/2 hp motor will use about 3.1 amps @ 120 volts. A 12 hp motor is a VERY large motor, and will draw 8900-9000 watts of power (and use 220-440 volt power)
How do you get single phase 440 from three phase 440?
You Don't. 440volt 3-phase is actually 480 volts, taking a single phase gives 277Volts single phase. To get single phase 440 you would use one leg of three phase 440/760 three phase power.
How do you convert 110 kva 440 volts?
To convert 110 kVA at 440 volts to amperes, you can use the formula: Amperes = kVA / (Volts x 1.73) for three-phase systems. In this case, 110 kVA / (440 volts x 1.73) ≈ 143.37 amperes.
