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The motor will hum and act like it is trying to run it's commonly known as single phasing, it will also heat up quite rapidly and if you set up your circuit correctly and have the proper thermal overload protection on it it will trip and protect the circuit and the motor. If the problem is in the motor winding you will have to rewind the motor or replace it
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∙ 14y ago
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∙ 15y agoIf you mean a 3 phase motor is single phasing; it will run slow, pull very high amperage, and will eventually burn the motor up all the way. What is happening is that one of the windings in the motor is bad. You can test this by using an ohm meter to test continuity between each motor wire (lead). The meter should read a direct short from each phase to each phase, you may also want to check from each wire ,with the meter, to ground which will indicated grounded motor windings which is not good either. Make sure that your voltage going to the motor checks good, read voltage phase to phase and phase to ground to verify. Hope this was helpfull.
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∙ 13y agowhen single phase happens while running, the motor continue to run with two phases by tacking the current grater than the rated current, it may be more than the motor full load current. at this pint of time motor winding may burnt because of over current taken by the two phases.
with this two phases the motor will deliver the 75%of its full load.
but motor will not start with the two phase. because two phases will not provide the rotating magnetic flux.
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∙ 12y agoI'm not sure how you would even accomplish this. On a single phase motor you will have the wire for connecting power to the motor, and a return neutral (along with several other wires for other things). If you connect two phases together you create a short and you'll blow the upstream fuse/breaker.
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∙ 12y agoIf one phase is present for a three phase motor? Then field can't produce sync rotating mag field, hence no rotation in the rotor. If two phases fails while load running then the load angle increases thus motor comes to rest. If it has no load then small size motors may continue rotation as of single phase motors
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∙ 9y agoSingle phasing of a three phase motor occurs when one input source line becomes open. This could be caused by a fuse blowing in the secondary side of a step down transformer supplying the three phase voltage source or one leg of a primary line becoming open. On motor operation this drives the other two lines higher than the normal operating current at which the motor is supposed to operate at. A three phase motor will run in a single phase condition but will not start. This is the reason that the overload protection was changed from two line protection to three line protection so that any combination of line failure would trip the motor's protection overloads and drop the motor's contactor open. By taking the motor off line, the motor is protected from excessive heating due to having more current applied to the motor than the motor's manufacturer recommends.
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∙ 11y agoA single phasing results in increase in current by 1.732 times the current drawn by motor before the fault occurs.
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∙ 11y agoif one phase of an 3 phase induction motor is damaged then it will become single phasing. Due to this the motor may burn out,if motor is running at their full load
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∙ 9y agoIf it's running when one phase is disconnected, it could continue running but only if there is a light mechanical load. With a normal mechanical load it would be expected to stall.
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What is the purpose of single phase preventors used in motors starters?
Phase monitors are used to detect single phasing, or loss of one phase of power from a three phase system. Most of the time they are used on very expensive motors such as high horsepower. They will shut down the starter, therefore shutting down the motor if all three phases are not available. One cause of this would be if there are three separate fuses protecting the motor and only one of them blows. The reason they are needed is because if you only send two phases to a three phase motor, it has a good chance of burning out the motor.
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.
Can you connect a 3 phase motor to a 1 phase supply?
Single phase to three phaseThe physical internal windings between single phase and three phase motors makes this an impossibility That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.Some 3 phase motor speed controllers can be run off a single phase supply, this caused us a problem at work when a new speed control was fitted to some laundry equipment, as we then had to rewire the supply to bring in a nuetral, so i suggest a speed controller is probably the solution.
What will happen when three phase induction motor run with two phase supply?
Yes, a three phase motor can run on a DC supply. You will need to provide an inverter, or a motor-generator set to do so. (In practical terms, the answer is no, because the costs will be high for any kind of significant power.)
Can a 3 phase motor be wired to run in your house?
The physical internal windings between single phase and three phase motors makes this an impossibility That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Otherwise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start. You can make a phase converter with a couple extra motors. Wire up a 120V single phase motor and couple it to a 3 phase motor. This turns the 3 phase motor into a generator for you to run to whatever equipment the 3 phase motor is. Although if you had a single phase motor you probable don't need a 3 phase motor. == == yes! you will have to buy a phase converter. yes, it is possible to this with a rotary phase converter . one manufacturer is "phase master" (as an example only, not wishing to promote any brand). these are not cheap units and it may be more cost effective to purchase a single phase (220V.) replacement motor . the overall efficiency (operational costs) would be better too . a rotary phase converter is usually the "last choice on the list" .
What happen If one phase of the three phase induction motor is not supplied?
If the motor was lightly loaded it may continue to run, however in most applications the loss of the phase would cause the motor to stop. Properly wired and it should trip the motor overload device and prevent damage to the motor windings.
Can you convert a three-phase motor to a single-phase motor?
Use only one of the legs (L1-L3), and the neutral. Some three phase circuits don't have a neutral. If that is the case, then you cannot run single phase.CommentYou don't need a neutral, providing the voltage is appropriate, you can get a single-phase supply by connecting the load between any two lines.
What is the purpose of single phase preventors used in motors starters?
Phase monitors are used to detect single phasing, or loss of one phase of power from a three phase system. Most of the time they are used on very expensive motors such as high horsepower. They will shut down the starter, therefore shutting down the motor if all three phases are not available. One cause of this would be if there are three separate fuses protecting the motor and only one of them blows. The reason they are needed is because if you only send two phases to a three phase motor, it has a good chance of burning out the motor.
What is the losses of three phase induction motors?
Iron Loss Copper Loss Frictional loss
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.
Can you connect a 3 phase motor to a 1 phase supply?
Single phase to three phaseThe physical internal windings between single phase and three phase motors makes this an impossibility That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Other wise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.Some 3 phase motor speed controllers can be run off a single phase supply, this caused us a problem at work when a new speed control was fitted to some laundry equipment, as we then had to rewire the supply to bring in a nuetral, so i suggest a speed controller is probably the solution.
What will happen when three phase induction motor run with two phase supply?
Yes, a three phase motor can run on a DC supply. You will need to provide an inverter, or a motor-generator set to do so. (In practical terms, the answer is no, because the costs will be high for any kind of significant power.)
How can you include phase failure relay in your star delta motor starter circuit?
The star delta motor starter circuit has to have a control voltage to energize the motor magnetic contractors. A phase failure relay monitors all three phases of the incoming supply lines. The phase failure relay also has auxiliary contacts on it. There are usually two sets of "C" form contacts. The control voltage for the starter circuit must be connected across the normally open (N.O.) contacts of one of these two sets. When the phase monitor is energized these N.O. contacts close supplying the control voltage to the circuitry of the star delta starters. If there is a phase interruption, phase reversal or phase loss, the phase failure relay will de-energize and the N.O. contacts will go back to their de-energized state. If the star delta motor starter is in use at the time, its control circuitry voltage will be lost and the delta motor magnetic contactor will open. The opening of this contactor will disconnect the motor from the failed three phase supply.
Can a 3 phase motor be wired to run in your house?
The physical internal windings between single phase and three phase motors makes this an impossibility That being said money can make anything happen. Depending on the amount of money you want to spend to make this happen there is a device on the market called a VFD ( Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Otherwise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start. You can make a phase converter with a couple extra motors. Wire up a 120V single phase motor and couple it to a 3 phase motor. This turns the 3 phase motor into a generator for you to run to whatever equipment the 3 phase motor is. Although if you had a single phase motor you probable don't need a 3 phase motor. == == yes! you will have to buy a phase converter. yes, it is possible to this with a rotary phase converter . one manufacturer is "phase master" (as an example only, not wishing to promote any brand). these are not cheap units and it may be more cost effective to purchase a single phase (220V.) replacement motor . the overall efficiency (operational costs) would be better too . a rotary phase converter is usually the "last choice on the list" .
What can we do to change 3 phase motor into single phase?
The physical internal windings between single phase and three phase motors makes this an impossibility. That being said, money can make anything happen. Depending on the amount of money you want to spend to make this happen, there is a device on the market called a VFD (Variable Frequency Drive). On the three phase input terminals you apply your single phase voltage. On the output terminals you connect your three phase motor. When run in this configuration, there is an internal switch that has to be changed to let the VFD know that it should be looking for only two lines on the input to be hot. Otherwise the VFD thinks that there is a line loss on the three phase input terminals and the unit will not start.As always, if you are in doubt about what to do, the best advice anyone should give you is to call a licensed electrician to advise what work is needed.If you do this work yourself, always turn off the powerat the breaker box/fuse panel BEFORE you attempt to do any work ANDalways use an electrician's test meter having metal-tipped probes(not a simple proximity voltage indicator)to insure the circuit is, in fact, de-energized.IF YOU ARE NOT ALREADY SURE YOU CAN DO THIS JOBSAFELY AND COMPETENTLYREFER THIS WORK TO QUALIFIED PROFESSIONALS.
What is phase loss?
Phase loss is the loss of power to a specific area of the circuit. Phase loss can result from exposed wires or damaged wires or even downed power lines.
Can 1 phase be used with 3 phase?
If you have a 208Y/120 volt 3 phase system, you can use any one of the three phases (hot or ungrounded conductor) with the neutral for 120 volt load or you can use any two phases of the three phase for a single phase 208 volt load. If you have a 120/240 volt 3 phase system, you can use any two phases of the three phase for a single phase 240 volt load or you can use either the A phase or C phase with the neutral for a 120 volt load. You can not use the B phase with a neutral (you would have 208 Volts!).
