Electrical Insulation is subject to many effects which can cause it to fail - mechanical damage, vibration, excessive heat or cold, dirt, oil, corrosive vapors and moisture in the air. In varying degrees, these enemies of insulation are at work and through the passage of time and with electrical stresses, pin holes or cracks can develop allowing moisture and foreign matter to penetrate the surfaces of the insulation.

Having moisture and foreign matter enter into insulation leads to a low resistance path for leakage current. A drop in insulation resistance can be sudden like when equipment is flooded, but most times the drop is gradual, giving plenty of warning if checked periodically.

Reduce the risk of failure, unexpected downtime and expensive emergency repair costs by testing your generator for insulation problems with a Megohmmeter test. Using a portable handheld tool, Holt of California's trained technicians can perform the Time-Resistance Method test on your generator insulation to determine its condition.

Megohmmeter testing can be applied to most simple circuit electrical equipment and devices, including:

• Wiring
• Motors
• Switches
• Generator Windings
• Transformers