Electric motor

Sensors on the motor continuously record vibration, temperature, speed or current draw and send the values to an IoT platform. There, software compares the readings with defined limit values. If a value deviates, the system raises an alarm, for example by email or on a smartphone. Typical motor faults such as imbalance, shaft misalignment or rolling bearing damage are detected before they cause a standstill.

Continuous condition monitoring makes electric motor maintenance plannable, because damage becomes visible before the motor fails. Without monitoring, motors often run until they break down, and plants have to keep many spare motors in stock. In the ifm solution, the moneo platform automatically creates a notification or work order in the SAP maintenance module via an interface when it detects a motor fault, and triggers the procurement of spare parts.

Current draw reveals electrical and mechanical problems that vibration measurement alone does not capture. To monitor a fan motor, an ifm current transformer measures all three phases between frequency inverter and motor. Deviations point to short circuits in the motor winding, stiff rotating parts or faults in the inverter. The transformer is clipped around the cable, so the machine does not have to be shut down for installation.

Vibration analysis shows whether a motor's mechanical condition is deteriorating and gives clues to the cause. In a steelworks, Honeywell sensors on a fan motor reported the ISO 10816-3 status “Damage Occurring”. The frequency spectrum showed conspicuous orders on the drive end and non-drive end, and an inspection of the bearings was recommended. After the motor was replaced, vibration values were below 1 mm/s.