Moisture protection for high-voltage motors?
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In actual chemical production, chemical pumps are usually operated continuously, which means that the motors of the backup pumps have to be protected from moisture. This is especially true for high-voltage motors, such as those with 10,000 volts; it seems that electric heaters are used to keep them dry. I didn’t see any such electric heaters on site – are they installed inside the motors? I’m seeking advice from all the experts! Thank you. This post was last edited by zhang*aobin on 2009-4-8 at 18:47.]
In ordinary high-voltage motors, the electric heater is built into the motor itself; the motor’s wiring box contains special terminals for connecting the electric heater. The heating voltage is usually 380V, and the power rating is determined based on the size of the motor. Check to see if such a wiring box and terminals are available.
Small high-voltage motors do not have electric heating; if specified at the time of ordering, it can be installed alongside the wiring box in larger models
My understanding is not what was said upstairs. Does it heat up by directly applying electricity to the coil?
Electric heating is a dedicated electric heating device, usually connected to the power supply of the oil pump in the light oil station
Electric heating is a dedicated electric heating device; the motor is located inside, the wiring box is on the outside, and it has an independent power supply that can also be connected temporarily.
Regularly blow air on the motor rotor using a fan; if it remains too humid for an extended period, it needs to be sent back to the factory, otherwise it poses a risk.
I went to the site to take a look, and there indeed was a heating element wiring box on the motor; however, the voltage of the heater for a 10,000-volt motor is 220V, with a power output of 680KW. On the other hand, there is a 380V motor that also has an electric heater junction box. Is there also a moisture protection requirement for 380V?
A dedicated electric heater is installed inside the motor housing; it is usually powered by a low-voltage source and has a power rating of several hundred watts, as specified in the motor’s manual.
The high-voltage motor I use is 6KV. During normal operation, it is powered by a 6KV supply; when not in use for an extended period, a 380V supply can be applied directly to the stator of the motor. Due to the high impedance of high-voltage motors, applying 380V will not make the motor move, but it will generate some heat in the stator, which helps to prevent moisture from entering.
This is exactly the kind of response from a moderator that I needed; thank you so much!
Do motors that are in standby mode need to have their electric heaters turned on all the time, whether it’s summer or winter? Are there any special requirements regarding the season?
No, it depends on the weather conditions. If the air is relatively humid or if the machine is shut down for a long time, it needs to be powered on and heated up.
In fact, all motors have moisture-proofing issues; it’s just that we pay more attention to certain important motors. The 10KV large-scale units you mentioned are equipped with electric heaters, and there are also dedicated heater power junction boxes as well as temperature-sensing cables in the vicinity of the power connection boxes. Inside the motor’s cavity, resistance wires are installed (similar to those found in heat trace systems). Some important 380V low-voltage motors also have such devices – similar to high-voltage switchgear, they too contain electric heater systems designed to remove moisture.
It is generally used only during rainy and overcast weather in the south; it is not usually necessary in the north. High-voltage motors are typically equipped with electric heating, which operates on an independent power source and is activated only before starting