Use of high-voltage motor heaters
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For high-voltage motors with a heater of 220V and 1000KW, it is generally said that the heater can be turned on three days before starting the pump, in order to prevent the stator from having poor insulation due to moisture (insulation resistance below 10 megohms usually requires heating). Is this statement correct?
The heater is generally interlocked with the motor in such a way that it turns on automatically when the motor does not start, and it turns off automatically when the motor starts. This ensures that the motor windings do not become damp
This statement is correct. High-voltage motors generally are equipped with resistance heaters, as they require high insulation standards, have large capacity, and are therefore expensive. Low-voltage motors usually do not have resistance heaters, as their insulation requirements are lower and their capacity is generally smaller. Resistance space heaters are used to prevent the windings from becoming damp and causing insulation damage; they can be linked to the motor’s start/stop functions, or operated manually, depending on the preferences of the operators. Their control circuits are typically implemented within the switchgear. If by “1000kW” you mean the power of the heater, then it is a mistake – the power of such heaters is generally between 500W and 2000W
For some high-voltage motors, when not in use, applying a 380V power supply to the stator can be used to bake the motor. It is correct to check the insulation resistance before driving.
Due to their high cost, high-voltage motors come equipped with comprehensive protection measures. Generally, it is necessary to check the insulation of their windings before each start-up, and the key to preventing a decrease in insulation quality is to keep the windings free from moisture. So a space heater is necessary.
When the motor stops running, the electric heater should be turned on
3# 22015805 I would like to ask: why is there a linkage between the motor’s heater and the motor itself, and why is there still a manual switch on the motor’s control panel?
“3# 22015805 I would like to ask: why is there a linkage between the motor’s heater and the motor itself, and why is there still a manual switch on the motor’s control panel? ” ----------I replied: The heater of the motor must be interlocked with the motor, because the motor generates heat during normal operation, and when this heat is added to the ambient temperature, it results in the temperature of the motor’s casing. Regardless of the insulation class of the motor, its insulation is affected by temperature. The electric heater also operates while the motor is running. Then the body temperature will exceed the normal operating temperature. Over time, the insulation is damaged, affecting the motor’s lifespan. If the motor itself has a high temperature rise, its insulation will be damaged quickly, making it easy for the motor to burn out. A panel with a switch allows for control of the electric heater at any time.
Are there corresponding regulations? ! ! ! !