The variable speed reduction motor should be regularly inspected during operation. Pay attention to monitoring changes in voltage, current, temperature, sound, and odor during inspections. The specific monitoring items are as follows:

  (1)       Monitor whether the voltage and current are within the allowable range, and pay attention to whether the three-phase voltage and current are balanced. If an ammeter is not installed, a clamp ammeter can be used for measurement.

  (2)       Pay attention to the operation of the bearings. For oil ring bearings, it is necessary to observe whether the oil ring rotates, whether the oil level is normal, and the maximum temperature of the bearing should not exceed 80 ℃. For rolling bearings, observe for oil leakage and color changes, listen for normal sound, and the maximum temperature of the bearing should not exceed 95 ℃.

  (3)       Observe whether there is any fire, missing corners (edges), jamming, too short, exposed copper plates, spring detachment, etc. on the electric brush. The protective cover of the electric brush should be intact.

  (4)       Check if the cooling air is unobstructed and closely monitor the temperature of the motor. For motors without temperature measurement devices, the temperature can be estimated based on experience using the tactile method: the motor shell feels very hot when touched by hand, but can continue to be placed on it for a few seconds, and the motor generally does not overheat; If the hand is so hot that it immediately retracts and small droplets of water make a "sizzling" sound and quickly evaporate, the electric motor may overheat. At this point, the temperature of the motor can be measured using a thermometer or resistance method to determine whether the motor can continue to operate.

  (5)        Keep the variable speed reduction motor and its surrounding environment clean, and there should be no debris, water, oil, etc. around the motor to prevent debris from falling into the motor. Regularly wipe the motor.

  (6)       Check for significant vibrations and noises in the unit, smell the burnt smell of insulation breakdown in the motor, and observe for sparks inside.