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What is the purpose of running overload protection for a three phase motor?
Wiki User
∙ 12y ago
An electrical circuit is designed to carry a certain amount of energy, or voltage. The flow of energy, called a current, should travel through the path from one point to the other unimpeded. If that current is interrupted, it causes what is commonly known as a short circuit. If an electrical system is designed properly, overload protection kicks in to stop the flow of energy until the source of the interruption is removed.
Wiki User
∙ 10y ago
Wiki User
∙ 12y agoThe purpose of using any overload protection on any motors, single phase or three phase, is to eliminate the possibility of allowing the motor to get into an overloaded condition. By disconnecting the motor from the supply voltage in an overload condition the motors winding's insulation is not subjected to high heat. High heat in the motor windings breaks down the insulation material and will eventually short circuit the windings causing the motor to have to be replaced.
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A device with a overload protection used to control a motor is a?
A device with an overload protection used to control a motor is an Overload Relay.
How is thermal overload protection done in stator windings of motor?
one way is to use RTD sensor put inside the motor windings. The RTD sensor is connected to an electronic thermal overload relay. This type of relay can provide running temperature of the motor, on the electronic thermal over load relay display panel. RTD sensor is a wire wound resistor that changes resistance depending on the temperature
How do you do for phase sequence protection at three phase motor operation?
motor is designed to operate in forward and reverse direction for the purpose of elevator. Phase sequence protection is not required.
How do you calculate 3 phase motor overload relay setting?
overload model no Ke-FKR4(D)
What measures should you take in order to rewind a motor for three phase?
Remove the motor from the system. Get the motor rewound at a motor rewinding shop. Replace the motor back into the system. While the motor is at the rewind shop find out why the motor burnt out. The first thing that should be checked is the overload protection. Make sure that is is the same as the motors full load amps.
A device with a overload protection used to control a motor is a?
A device with an overload protection used to control a motor is an Overload Relay.
What is the conclusion of overheat protection of induction motor?
If the overload protection is set correctly to the motors full load amperage, any overloading of the motor will trip the protection and take the motor off line. Once the reason of the overload has been established and rectified, the overload protection is reset and the motor can be brought back on line.
How do you set motor amp overload?
There are many types of overload protection these days and all are based on the FLA (full load amps) of the motor.
What is the purpose of the internal overload protector in the compressor motor?
No
What will happen to a motor that is running that suddenly receives a heavy load?
The RPM of the motor will momentarily slow down, the current will go higher until the motor gets up to speed again. The motor will then go back to normal operation. If the load is in excess of the horse power rating of the motor, the motor will go into overload and the current will go higher that nameplate rating. If left in this condition the overload protection should trip the motor off line. If there is no protection on the motor, the life span of the motor is shortened likely from insulation failure.
Will 3 phase AC motor stay running if you remove 1 phase?
Yes but it will not start. Usually if you lose one phase the current will go higher on the other phases and the motor overload protection will disconnect the motor from the supply voltage.
What issues can burn a three phase delta star motors?
In reality if the proper motor protection is used, no motor should burn. Even a motor that has a locked rotor will trip the heater overload protection. So the issues to be looked at that would cause a motor to burn would be, is the motor protection correctly sized? The motor must be running within the manufactures specifications and not outside the motors service factor. The supply breaker and wiring to the motor must be the correct size. The overload protection should be in mid scale of the settings. House keeping around motors is a big condition to keep a motor running within its parameters. Cooling fins and fans must be kept clean of any debris. All of this should allow a motor to run free of trouble for many years.
What will cause a star delta panel to trip in delta?
On a star delta starter a motor overload or a motor going to ground and cause a short circuit will cause the overload protection to trip. These overloads have to be reset before the motor can be restarted.
How is thermal overload protection done in stator windings of motor?
one way is to use RTD sensor put inside the motor windings. The RTD sensor is connected to an electronic thermal overload relay. This type of relay can provide running temperature of the motor, on the electronic thermal over load relay display panel. RTD sensor is a wire wound resistor that changes resistance depending on the temperature
In what condition does a motor gets burnt out when running at rated load?
If overload is not the cause, then high temperature could be caused by blocking the cooling of the motor.
What is the necessity of the starter.Can a single pole switch replace it?
A motor starter usually has an overload heater incorporated into it. A single pole switch does not have that type of protection. There are many brands of fractional motor starter switches. These types of switches are sized by the motors full load amperage. These types are dual purpose being that they can be used as the motors isolation switch and also they can be used as motor protection for the connected motor.
What is overload protection?
It is protection installed to protect, usually motors, from going beyond the amperage capacities that were set down by the manufacturer's specifications of the motor. As a motor loads up to its rated HP it will operate within the motors amperage range. More loading on the motor will increase the amperage draw to a point where the motor's winding will start to burn or short out due to insulation breakdown of the motor coils. Over load protection is a settable device that will limit the current to a specific value. The setting on the over current device is the motor's FLA (full load amps). If the motor amperage goes higher that the set point the overload protection, the overload protection contacts will open and drop the motor's magnetic contactor off line. In some cases this could be an annoyance but it does save the motor from destroying itself.
