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A relay is not essential but larger motors have a relay which operates above a certain speed, to cut out the start capacitor, which improves the power factor and reduces power losses.
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Can you change a 440 volt 12.5 uF start capacitor with a 370 volt 12.5uF run capacitor?
There are two ways to read this: you have a burned-out run capacitor on your motor and a good start capacitor in your parts box, and you have a burned-out start capacitor and a good run capacitor. If the run capacitor's bad and you want to put the higher-voltage start cap in its place, the answer is yes. This is called derating, and the only thing it does for you is increases the lifespan of the capacitor because you're not working it as hard as it can take. If the start capacitor's bad, don't do this--they used a 440-volt capacitor in there for a reason.
My motor is 220volt single phase what voltage should the starting capacitor be The capacitor that is in it is only rated at 125 volt 500 MFD This is a 2 HP motor?
The voltage rating for a start capacitor must be at equal to the motors line voltage or greater.The formula used to find the value of a motor starting capacitor is 2650 X FLA/VAC = mfd.See related link below, page 462 to 465 for full details about motor capacitors
Why do you connect a capacitor to an AC motor?
To induce a phase shift between the rotor and stator (stationary winding). AC motors are not good at starting up, they need 'help' to get started/they need two magnetic fields to push against each other to generate torque. This capacitor is called a 'starting' capacitor and provides an extra 'boost' to get the motor turning by increasing the phase angle between the rotor and stator winding. Once the motor is at it's proper operating speed, the capacitor must be disconnected or it will burn up. There are also motor designs that use a run capacitor. This capacitor usually has a smaller capacitance than a start capacitor (so it provides a smaller phase shift), but is designed for continuous operation. These motors don't provide as much starting torque as a similar motor with a start capacitor. Other motors will have both a start and run capacitor. The start capacitor provides significant phase shift between the rotor and stator, and thus significant torque. Once the motor is at speed, the start capacitor is switched out of the circuit, and the run capacitor is left in the circuit to provide a smaller phase shift.
Wiring Diagram for capacitor start motor with centrifugal switch?
It is not clear what exactly is being asked-for in this question. If it could be asked again, with a bit more detail as to what part of a household 110-120 Volt circuit is required, someone may be able to give a better answer than this one.
Why is capacitor start motor used in printing press?
To offset the magnetic field so the motor can rotate without being caught in between the two poles where they resist rotation. Example, is where a motor is humming, but there is no rotation. However, if you kick start the rotation with a slight push then the motor rotates. This is caused by the two poles that are equal in resistance for pull and push.
Can you change a 440 volt 12.5 uF start capacitor with a 370 volt 12.5uF run capacitor?
There are two ways to read this: you have a burned-out run capacitor on your motor and a good start capacitor in your parts box, and you have a burned-out start capacitor and a good run capacitor. If the run capacitor's bad and you want to put the higher-voltage start cap in its place, the answer is yes. This is called derating, and the only thing it does for you is increases the lifespan of the capacitor because you're not working it as hard as it can take. If the start capacitor's bad, don't do this--they used a 440-volt capacitor in there for a reason.
My motor is 220volt single phase what voltage should the starting capacitor be The capacitor that is in it is only rated at 125 volt 500 MFD This is a 2 HP motor?
The voltage rating for a start capacitor must be at equal to the motors line voltage or greater.The formula used to find the value of a motor starting capacitor is 2650 X FLA/VAC = mfd.See related link below, page 462 to 465 for full details about motor capacitors
Why do you connect a capacitor to an AC motor?
To induce a phase shift between the rotor and stator (stationary winding). AC motors are not good at starting up, they need 'help' to get started/they need two magnetic fields to push against each other to generate torque. This capacitor is called a 'starting' capacitor and provides an extra 'boost' to get the motor turning by increasing the phase angle between the rotor and stator winding. Once the motor is at it's proper operating speed, the capacitor must be disconnected or it will burn up. There are also motor designs that use a run capacitor. This capacitor usually has a smaller capacitance than a start capacitor (so it provides a smaller phase shift), but is designed for continuous operation. These motors don't provide as much starting torque as a similar motor with a start capacitor. Other motors will have both a start and run capacitor. The start capacitor provides significant phase shift between the rotor and stator, and thus significant torque. Once the motor is at speed, the start capacitor is switched out of the circuit, and the run capacitor is left in the circuit to provide a smaller phase shift.
Should a motor with start capacitor have a start relay?
The compressor motor employs both a start and run winding. The run winding is energized during the complete cycle of operation, whereas the start winding is energized only during the starting period. The current-operated type of relay has a coil connected in series with the run winding of the compressor. Some current-operated relays plug directly onto the compressor while others do not. Most relays are mounted in a case located on the compressor. When the thermostat closes, the compressor attempts to start, drawing heavy current through the run winding and the relay coil. This strong current flow through the relay coil creates a magnetic field strong enough to cause the start contacts to lift and close, energizing the start winding. When the compressor reaches approximately 3/4 running speed, the current flow through the relay coil decreases (due to the countering electrical magnetic field in the motor) and as the magnet weakens, the start contacts fall open. This type of relay must be used with an overload protector and must be mounted in an upright position, so that the contacts can fall freely to the "open" position.
Should a motor with a start capacitor have a start relay?
The compressor motor employs both a start and run winding. The run winding is energized during the complete cycle of operation, whereas the start winding is energized only during the starting period. The current-operated type of relay has a coil connected in series with the run winding of the compressor. Some current-operated relays plug directly onto the compressor while others do not. Most relays are mounted in a case located on the compressor. When the thermostat closes, the compressor attempts to start, drawing heavy current through the run winding and the relay coil. This strong current flow through the relay coil creates a magnetic field strong enough to cause the start contacts to lift and close, energizing the start winding. When the compressor reaches approximately 3/4 running speed, the current flow through the relay coil decreases (due to the countering electrical magnetic field in the motor) and as the magnet weakens, the start contacts fall open. This type of relay must be used with an overload protector and must be mounted in an upright position, so that the contacts can fall freely to the "open" position.
Do all motors that use capacitors must have at least one run capacitor or a run and start capacitor true or false?
true
Where is the relay switch located for wipers in a 1996 Saturn SL as the fuses are good?
the relay is part of the wiper motor assembly. if the fuses are good, and there is voltage at the motor, then you must replace the motor
Wiring Diagram for capacitor start motor with centrifugal switch?
It is not clear what exactly is being asked-for in this question. If it could be asked again, with a bit more detail as to what part of a household 110-120 Volt circuit is required, someone may be able to give a better answer than this one.
Is there a relay for the wiper motor on a 1995 Chevy G20 Van?
everything is built into wiper motor including delay timer. there is a fuse you must check no relay.
Why is capacitor start motor used in printing press?
To offset the magnetic field so the motor can rotate without being caught in between the two poles where they resist rotation. Example, is where a motor is humming, but there is no rotation. However, if you kick start the rotation with a slight push then the motor rotates. This is caused by the two poles that are equal in resistance for pull and push.
How do you differentiate a start capacitor from a run capacitor in air conditioner?
If the air conditioner has both, the run capacitor is likely the largest one. The start capacitor will only be in the circuit for a very short time, so overheating doesn't become an issue. The run capacitor must be sized for continual use.
What if your headlights do not come on when you start the truck But they do when you press the relay switch?
Whatever controls the relay must be broken, if everything beyond the relay works.
