Motor overload causes and solutions

Motor overload refers to the general motor has a fixed operating power, called the rated power, the unit is watts (W), if the actual use of the motor in a certain situation so that the motor power more than the rated power of the motor, the phenomenon is called motor overload.

In the main circuit of the motor there is a thermal relay (overload protection), when the motor overload, thermal relay action, normally closed contacts cut off the control circuit, normally open contacts closed to connect the indicator, overload excluded, the thermal relay contacts there are two reset to make the circuit restart work: manual reset – need to press the reset button; automatic Reset – overload removal, wait a while, it cools down and automatically return to normal. If you are in the manual reset position, find the thermal relay, press the red handle on it, and you can hear a “pop” sound.

Symptoms of motor overload

1. Motor heat increases;
2. Motor speed decreases and may even drop to zero;
3. The motor has a low chirping sound, vibration in general;
4. If the load changes drastically, the motor speed will be high and low;
   Causes and solutions of motor overload
   Air compressor in the process of operation, often appear motor operation overload phenomenon, air compressor in the loading state, the current exceeds the high limit (34A) delay 3s, then judged as air compressor motor overload fault, triggering sound and light alarm, exceeding the high high limit (37A) delay 3s, then interlocking to issue a trip command, and triggering sound and light alarm. So what are the reasons and solutions for air compressor motor overload?
   The voltage is too low and the power line is too thin. Models with thermal protector, thermal protector set too low, or failure, models with current transformer, the system set current is too low. Contactor contacts are bad, etc., the three filters are seriously clogged. Minimum pressure valve seal failure, host or motor blockage or bearing damage will make the air compressor motor overload.
   How to solve it? Minimum pressure valve seal failure, resulting in motor startup encounter load; minimum pressure valve pressure 0.7Mpa, mainly play a role in pressure protection, if the minimum pressure valve seal failure, then the best way is to replace the minimum pressure valve .
   Host or motor blocking or bearing damage, the host start time is set less than the star angle delay time will lead to blocking, then you need to reset the start time is greater than the star angle delay time.
   Serious blockage of the three filters; three filters include: air intake filter element, oil filter, oil sub-core, air compressor three filter blockage is mainly due to too much dust in the air compressor room or air compressor maintenance time to time, for this reason we mainly replace the air compressor three filters on it, in addition to suggesting that air compressor users in the air compressor room site selection time to pay attention to choose a less dusty, ventilated place, which will give air compressor maintenance later to reduce a lot of costs. This will reduce the cost of air compressor maintenance. Maintenance time to be sure to be on time maintenance, the cost of electricity consumption must be maintenance costs much more.