This is a must-read for electric motor repair personnel dealing with larger motors that need to determine the integrity of a squirrel-cage rotor and if it needs to be repaired in-house or outsourced.
In this timeless resource article, you will learn methods for how to determine broken and lose bars, voids in endings, cracks, vibration, overheating, and much much more….
- Most common reasons for squirrel cage rotor failure
- Learn methods for testing a squirrel cage rotor which has failed or is near failure
- How an induction rotor works
- The problems broken rotor bars can create
- 19 colored pictures and graphs
- And much much more
Disassemble Motor Rotor Testing Methods
Visual inspection of rotor failure:
- Balancing issues
- Cracked endrings
- Melted aluminum or copper
- Shifted laminations
- Casting flaws in endrings and bars
- Localized burnt spots
- Open bars
- And more
Testings methods
- Growler testing for open bars
- Coreloss testing for iron integrity
- High current excitation testing for open bars
- Spectrum analysis for vibration testing
- Tap testing for loose bars
- Dye penetration test for cracks
- Temperature paint testing for hot spots
- Ultrasonic testing for voids in endrings and cracks in the shaft
- Low resistance ohmmeter testing for broken bars
- High current low voltage transformer testing
- Thermal imaging
Download Your Free Industrial Rotor Testing Guide
Assembled Motor Rotor Testing Methods
- Single-phase testing for open bars
- Two ammeter comparison testing for open bars
- Stroboscope testing for speed issues
- Vibration analysis
- Motor current signature analysis for open bars
- Stray flux testing for open bars
