Is it allowed to start a high-voltage motor continuously?
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When a high-voltage motor fails and needs to be repaired before being restarted, and if the process requirements dictate that the motor must be restarted within a short time frame, is it permissible to do so from an electrical perspective? What are the consequences?
I’m not sure about your motor’s parameters, so it’s difficult to discuss this in detail. But how short is a short period of time exactly? Restarting within ten minutes should not pose any problems in principle. A high-voltage motor has a high voltage, not a high current!
Ordinary low-voltage, low-capacity motors allow restart after a short shutdown, but frequent starting is not recommended. The main concern is that the high starting current during startup can cause the motor to overheat and get damaged; however, the surface temperature of the motor does not rise significantly in the short term. Especially, high-voltage, high-capacity motors take longer to start and are more prone to overheating. Motors of 200kw and above are allowed two consecutive starts in cold condition, with an interval of more than half an hour when hot. For motors of 1000kw and above, the interval between operations in a cold state is half an hour, while the interval in a hot state is 2–4 hours or more. It is related to the size of the motor capacity.
This post was last edited by zhaohh3211 on 2011-9-5 20:01. Our factory requires that a high-voltage motor must wait for half an hour before it can be restarted after tripping.
It depends on the different manufacturing process requirements of each company. For the 6300KW motor in our unit, it trips and then restarts.
This post was last edited by zhaohh3211 on 2011-9-5 20:02; it should be over half an hour.
What was said on the 3rd floor is absolutely correct; we follow the regulations strictly, as starting the motor again after it stops working would cause problems. By eliminating all factors that lead to abnormal shutdowns, there will be no need to rush to start the motor. Proper maintenance should be carried out, and components should be replaced when necessary to avoid troubles. Ordinary low-voltage, low-capacity motors can be restarted after a short period of shutdown, but it is recommended not to start them frequently. The main concern is that the high starting current during startup can cause the motor to overheat and get damaged; however, the surface temperature of the motor does not rise significantly in the short term. Especially, high-voltage, high-capacity motors take longer to start and are more prone to overheating. Motors of 200kw and above are allowed two consecutive starts in cold condition, with an interval of more than half an hour when hot. For motors of 1000kw and above, the interval between operations in a cold state is half an hour, while the interval in a hot state is 2–4 hours or more. It is related to the size of the motor capacity.