Electrical Motor Testing Maintenance
Gain Reliability & Return Energy Savings.
The "As found" Resistance test showed a defect. Look what we found!
Burnt cable terminations, Bad Crimps, Deformed Lug, Lugs the wrong size, and Nuts loose.
"As Left" a drop in resistance and a gain of 3500 GBP
How do you implement Electrical Preventative Maintenance?
By far the biggest impact you can have is testing for Resistance at the Panel (MCC) so the total circuit is measured using a MilliOhm meter or better. You are looking for Imbalances above 3%, and for motor 75kW or above the absolute resistance should be below 10 milliOhm.
Resistances for smaller motors should be no larger than 1.5 Ohms.
Secondly measuring Impedance has a limit of 3%, this tells you the current flowing in each phase.
Winding & Insulation test are next, while an Insulation Resistance test is good it is what I called a late stage test. Meaning your close to failure and your Preventative Maintenance Schedule may miss the defect and the motor fail. Surge or Stepped Frequency test are used but I prefer the later.
These tests should be date & time stamped and attached to your CMMS (Computerised Maintenance Management System). This is useful for Insurance Risk Audits which also is a financial benefit.
