Understanding the concept of Resistance in Motors


Understanding the concept of Resistance in Motors

An Ohmmeter is used to measure the electrical resistance between two points.  A Micro-ohmmeter is used to measure low resistance circuits.  A Meg-Ohmmeter is used to measure high resistance circuits.  The unit of measure for resistance is an ohm.

When testing electric motors, it is useful to know the insulation resistance between motor winding(s) and the frame ground.  This value will normally be in the range of tens to millions of ohms.

However, motor winding faults can also occur within the winding and is not detectable using the Meg or Micro-Ohmmeters.  For these types of tests, other types of instruments must be used, such as the portable, light weight, hand-held, de-energized motor testers offered by ALL-TEST Pro.

ALL-TEST Pro provides hand-held, battery operated, field portable test instruments designed to evaluate the entire electrical health of the motor.  This included detecting developing coil-to-coil, turn-to-turn, and phase-to-phase short circuits before they become catastrophic. These instruments will enhance trouble-shooting efficiency, improve your electric motor maintenance program, and help avoid unplanned production outages.



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