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Look on thew nameplate of the motor to see if it is thermally protected. This means that there is overload protection on the inside of the motor next to the windings. If the temperature rises in these windings the motor will trip off line and stop. Once the motor cools down the thermal overload device will reset and the motor will start again the next time you try it. As the answer states below reduce the load.
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How about over heating. To much load caused by bad bearings. Simply to much load.
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Can a bad circuit breaker on a 3 phase motor cause the motor to run backwards?
No. If the motor runs backwards, swap any two phases to reverse the rotation, like this: Old wiring: phase A - brown wire - motor lead T1 phase B - yellow wire - motor lead T2 phase C - orange wire - motor lead T3 New wiring: phase A - brown wire - motor lead T2 phase B - yellow wire - motor lead T1 phase C - orange wire - motor lead T3
What is the use of centrifugal switch in single phase induction motors do all single phase motors gave them?
To stop a three-phase motor dead ('plugging'), rather than allowing it to slow to a stop, the motor controller interchanges two of the three lines -which applies a reverse torque to the machine. But before the motor then gets a chance to reverse direction, the centrifugal switch trips the starter and removes the supply. <<>> The centrifugal switch that you refer to and can see in an open frame motor, is used to open the start winding of small HP single phase motors. Once the motor gets up to a certain RPM, the switch opens and the motor continues to operate on its run winding. When the motor stops, the switch goes back to its normally closed position in the start winding and awaits the next start operation.
Can you replace the 5HP 3 phase motor on your compressor with a single phase motor of the same HP?
Yes BE SURE TO Check RPM 5hp at 1800 rpm needs 25hp at 3600 rpm caveat : single phase motors are bigger physically consume more power and run at higher current (73% higher current) and take longer to get up to speed so the frame size may be different shaft size and bolt circle height of the shaft etc this is an easy task with a belt drive with the single bearing motor on some smaller compressors its impossible another possibility: small drives for 3phase motors have come down in price and may work just fine on single phase and may be cheaper than a single phase motor... can perhaps do pressure regulation by varying the speed of the motor instead of the noisy on off stop start ... fill the tank and idle speed up with demand...wont need to blow the air for the unloader soft start will increase the life of all the mechanical stuff
Assuming that the listed exception do not apply the NEC states that the minimum number of overload units required for a three-phase alternating current motor shall be?
Each leg of a three phase motor must have overload protection. There is no minimum. Older magnetic contactors used to only protect two legs but occasions arose out of this configuration that would cause the motor to single phase on an overload condition. The code was changed to stop this condition from happening so now all three legs must be protected.
Why an electrical device will not work if the neutral is not connected in a single phase system?
To make any electrical circuit work it has to be complete. Source of power to the load, the load itself and a return path from the load back to the source. The source in this case being the distribution panel. Any breaks in this complete path will cause the current to stop flowing and the device to not work. A light fixture and light switch work on this principle, open the circuit and the light goes out.
Can a 240 volt single phase motor be supplied with one phase until the other phase is closed without harming the motor?
Not a good idea. Use a double pole single throw switch to start and stop the motor if motor HP is small. Use a motor contactor on larger HP motors.
Can a bad circuit breaker on a 3 phase motor cause the motor to run backwards?
No. If the motor runs backwards, swap any two phases to reverse the rotation, like this: Old wiring: phase A - brown wire - motor lead T1 phase B - yellow wire - motor lead T2 phase C - orange wire - motor lead T3 New wiring: phase A - brown wire - motor lead T2 phase B - yellow wire - motor lead T1 phase C - orange wire - motor lead T3
How do you convert a 3 phase car lift to single phase?
The best way is usually to buy a new single-phase motor and replace the 3-phase motor. You can also buy something called a rotary phase converter, but for any amount of HP they are about as expensive as a new motor. Expect to pay 500 to 700 dollars US for a 10hp rotary converter. Static phase converters are not a good choice for motors that start and stop or reverse often, such as yours.
Why single phase induction motor taking more time for stop after disconnecting supply?
A motor runs on because of its inertia which causes it to run down until friction dissipates the kinetic energy of the rotor.
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.
What is the use of centrifugal switch in single phase induction motors do all single phase motors gave them?
To stop a three-phase motor dead ('plugging'), rather than allowing it to slow to a stop, the motor controller interchanges two of the three lines -which applies a reverse torque to the machine. But before the motor then gets a chance to reverse direction, the centrifugal switch trips the starter and removes the supply. <<>> The centrifugal switch that you refer to and can see in an open frame motor, is used to open the start winding of small HP single phase motors. Once the motor gets up to a certain RPM, the switch opens and the motor continues to operate on its run winding. When the motor stops, the switch goes back to its normally closed position in the start winding and awaits the next start operation.
How do you reverse a direction of a slip ring motor?
It is very simple. Just interchange any two phase wires. i.e. Y and B ( or ) R and B ( or ) R and Y for example Stop the supply. keep R phase wire as it is and disconnect B phase wire and Y phase wire. Connect B phase wire to the Y phase motor stud and Y phase wire to the B phase motor stud. Now give the supply, now motor revolves in opposite direction to the earlier.
Can you replace the 5HP 3 phase motor on your compressor with a single phase motor of the same HP?
Yes BE SURE TO Check RPM 5hp at 1800 rpm needs 25hp at 3600 rpm caveat : single phase motors are bigger physically consume more power and run at higher current (73% higher current) and take longer to get up to speed so the frame size may be different shaft size and bolt circle height of the shaft etc this is an easy task with a belt drive with the single bearing motor on some smaller compressors its impossible another possibility: small drives for 3phase motors have come down in price and may work just fine on single phase and may be cheaper than a single phase motor... can perhaps do pressure regulation by varying the speed of the motor instead of the noisy on off stop start ... fill the tank and idle speed up with demand...wont need to blow the air for the unloader soft start will increase the life of all the mechanical stuff
How can a single phase motor be rotated clockwise and then anticlockwise without any delay?
It can't, this is called plugging. The motor should come to a complete stop before reversing its direction. The heat build up in the rotor becomes excessive when plugging and should be used with discretion.See related links below.
Assuming that the listed exception do not apply the NEC states that the minimum number of overload units required for a three-phase alternating current motor shall be?
Each leg of a three phase motor must have overload protection. There is no minimum. Older magnetic contactors used to only protect two legs but occasions arose out of this configuration that would cause the motor to single phase on an overload condition. The code was changed to stop this condition from happening so now all three legs must be protected.
Why has your 3500 Honda single phase stop generating?
First check the obvious. See if the circuit breaker has been tripped.
Why an electrical device will not work if the neutral is not connected in a single phase system?
To make any electrical circuit work it has to be complete. Source of power to the load, the load itself and a return path from the load back to the source. The source in this case being the distribution panel. Any breaks in this complete path will cause the current to stop flowing and the device to not work. A light fixture and light switch work on this principle, open the circuit and the light goes out.
