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1 HP=746 watts 15 HP=11,190 watts Ohm's Law says Current (in Amps) = Power (in Watts) divided by Voltage (in Volts) 11,190 watts divided by 415 volts = 26.96 amps.
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For a three-phase motor each phase supplies one third of the power, so that is 5 HP on each phase. A 415 v supply has a line-to-neutral voltage of 240 v, and 3730 watts would therefore required 3730/240 amps, or 15.54 amps.
However due allowance must be made for (i) the power factor and (ii) the conversion efficiency. This would increase the current by an estimated 20% so the current is therefore estimated to be 19 amps.
Wiki User
∙ 9y ago
Wiki User
∙ 13y agoOne horsepower electric is 746 watts, so 7.5 horsepower is 5.6 KW. You don't say what the power factor or efficiency of the motor is, so I'm going to assume 0.92 PF and 0.95 EFF. Divide 5.6 KW by 0.92 PF to get 6.1 KVA. Divide 6.1 KVA by 0.95 EFF to get 6.4 KVA. Divide that by three to get 2.1 KVA per winding. You don't say if the 415 is delta or wye, so I am going to assume delta. Divide 2.1 KVA by 415 V to get 5.1 amperes per winding. Multiply that by the square root of three (1.732) to get 8.9 amperes per phase.
Allow for 25% margin and you get 11.1 amperes for the MCC. I would consider 12 or 15 amperes, but the nameplate on the motor has to take precedence.
Wiki User
∙ 10y ago5 HP is 5x746 watts and the motor is probably 90% efficient therefore the power required is 4144 watts. At a power factor of 0.8 that is 5180 VA.
On a 3-phase system star connected the line voltage is 240 v and each line supplies 1727 VA, therefore the line current is 7.2 amps.
Wiki User
∙ 11y ago7.5
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How does the 3-phase induction motor acts like 2-phase induction motor if a phase is disconnected from supply?
yes the motor will run but will draw more current and the torque will be not constant means not smooth due to unbalanced current
How much current will a 15 hp single phase 220 volt fan motor draw?
The wiring should allow for 115 amps.
Will a 10 hp 220 volt motor draw large amounts of electricity?
A single phase 10 HP motor will draw aproximately 50 amps. A three phase 10 HP motor will draw aproximately 28 amps.
Why motor burn at single phasing?
A 3-phase motor will not run on single-phase power or if one of the three phases is disconnected. If the motor is not running, there is no back-EMF generated in the coils, and they draw excessive current, thus overheating.
Can you wire a 3 phase 690 volt delta star motor to 480 volt 3 phase with out harming the motor?
Depends on the motor and the load on that motor. If the motor is loaded to its capacity, it will draw the same amount of power as it would on 690 volts - which will result in ( 690/480 = ) 144% of normal current, which will thermally damage the motor, or will trip overload protection.
How does the 3-phase induction motor acts like 2-phase induction motor if a phase is disconnected from supply?
yes the motor will run but will draw more current and the torque will be not constant means not smooth due to unbalanced current
What would be the horse power required in a 3-phase motor to replace a .5 horsepower single phase motor.?
You still need the same horsepower. The advantage of the three-phase motor is that it will draw lower current.
What is the phase current of a three phase 2.2kw 415v motor connected in star?
The line current would be the same if the motor were connected in delta. The current can be based on the rule of thumb which says 7 amps must be allowed for a 1-HP single-phase motor on 240 v. A 2.2 kW motor is three times as powerful, and on a three-phase supply of the same voltage (240/415) it would draw 7 amps.
Should all 3 phases of a motor draw the same amperage?
Yes. they should. The windings in a three phase motor are identical, and provided they are fed with a supply that has the phases at the correct voltage, and at the correct 'phase angles' to each-other, they should each draw the same current from each supply line. (Motor windings are a 'balanced' load - they will all draw the same current from the lines if the supply is okay and the windings are connected correctly, and have no shorts or opens in them.) Some three phase motors can be connected to run off of a single phase line, using capacitors to give phase shifts to simulate 3 phase. This is an 'unbalanced' 3 phase supply as far as the motor is concerned, and while it WILL work, the motor will develop less staring torque, less full load power, and more noise - and it WILL draw different currents in each 'phase' while running.
How much current will a 5 HP single phase 220 volt motor draw?
P=VI P=power V=voltage I=current therefore current drawn is 5000/400=50/4=12.5 amperes
How much current per phase will a 18KW motor draw on 415 v?
we can use the formula: Ip=KW/3/volts/pf
How much current will a 15 hp single phase 220 volt fan motor draw?
The wiring should allow for 115 amps.
Will a 10 hp 220 volt motor draw large amounts of electricity?
A single phase 10 HP motor will draw aproximately 50 amps. A three phase 10 HP motor will draw aproximately 28 amps.
Why motor burn at single phasing?
A 3-phase motor will not run on single-phase power or if one of the three phases is disconnected. If the motor is not running, there is no back-EMF generated in the coils, and they draw excessive current, thus overheating.
How many watts is 1 hp at 480volts?
A 1-HP motor is reckoned to draw 7 amps at 240 v single-phase. The same power of motor would draw 3.5 amps at 480 v single-phase, but a 480 v supply could most likely be a three-phase suppy, and the current in that case would be reckoned as 2 amps.
Is amp draw on a 220V motor per leg or combined?
Amp draw is always combined. 220V is uncertain if it is three phase or not, because there are both one phase and three phase applications of the 220V motor. In any case, the answer is always "combined".
Can you wire a 3 phase 690 volt delta star motor to 480 volt 3 phase with out harming the motor?
Depends on the motor and the load on that motor. If the motor is loaded to its capacity, it will draw the same amount of power as it would on 690 volts - which will result in ( 690/480 = ) 144% of normal current, which will thermally damage the motor, or will trip overload protection.
