Application report - Inspection of electric motors with portable stroboscopes


An electric motor is to be checked regularly in accordance with an internal maintenance regulation.

This inspection also includes the measurement of the speed and the inspection of the fan blades. The motor is checked for accumulation of dirt, damage to the blades and drag marks caused by contact with the housing.

The current production process should not be impaired during the inspection.


The following inspections can be made on the running motor with the portable stroboscopes RT STROBE pocket rolux, pocket LED and qbLED:

  1. The flash rate of the ROLUX is synchronized to the speed of the fan. The fan appears to be at a standstill at this rate. The speed can be viewed directly on the display.
  2. At the same time the fan can be inspected for dirt and damage in a “stationary” condition. 
  3. The reason for drag marks can be found and directly assigned to a certain load or speed, or even an individual blade.

The full report can be downloaded here: