Electrical Testing

York offers on-site Electrical Testing

We offer electrical testing to help determine the state of your equipment and to quickly diagnose any issues you may be having.  Whether the results garner preventative maintenance or a full repair, we have the technical knowledge to determine how to best keep you running, longer.  Here are the tests we commonly use:

Surge Testing

We use a brand new Baker surge tester.

Surge testing enables us to test the motor from:                                                                                          
• Phase to phase
• Phase to ground
• Turn to turn
We do this at 2 times the voltage +1,000.

D.C. HiPot

The DC Hi Potential test is performed by using a test voltage that is far greater than the Meg-Ohm test.  It should be based on the standard operating voltage of the motor.

• We look for unusually-high leakage currents, or one that intermittently jumps up and down.
• We check for damaged ground wall insulation. This damage is a result of breakdowns or high-leakage currents.
• We also inspect the motor’s slot liner, wedges conductors between the junction box and the coils.

Polarization Index (PI) Testing

The polarization index is the measurement of resistance to ground. It is useful in evaluating motor windings for:

  • Buildup of dirt or moisture.
  • Gradual Deterioration of the insulation (by comparing results of tests made earlier on the same machine).
  • Fitness for over-potential tests.
  • Suitability for operation.

Insulation Resistance “Megger” Testing

Insulation Test to ground.
We test the insulation system of the windings to see if the integrity, the breakdown of insulation, is becoming an issue, and to offer preventative solution if so.  Good insulation has high resistance, poor insulation has low.


Our professional Field Service department is dedicated to providing on-site repair services 24 hours a day, 7 days a week.

With over 40 years of experience in industrial repair, YORK is your complete equipment maintenance solution!

Call us today at (989) 684-7460 to set up a route at your plant!