Insulation Resistance Testers Address High-/Low-Voltage Equipment

Megger offers a series of insulation resistance testers that are capable of safely testing both high- and low-voltage equipment.  The MIT515, MIT525, MIT1025 and MIT1525 feature testing techniques that provide valuable diagnostic information.  Each of the instruments can easily test high-voltage power cables and buses, large motor/generator windings as well as line and substation transformers for insulation resistance.


Specifications include:

  • Maximum resistance range from 1 TΩ to 3TΩ
  • Rated for use at an altitude of 3,000 meters
  • Rapid charge lithium-ion battery
  • Maximum power transfer at 3 mA
  • Flexible silicon test leads
  • Large backlit LCD screen 

Rated at 5 kV and 10 kV, the MIT515, MIT525 and MIT1025 are engineered to ensure the highest precision possible.  Both 5 kV units offer 5% accuracy up to 1 TΩ, while the 10 kV unit offers 5% accuracy up to 2 TΩ.  The 15 kV model, MIT1525, offers a 5% accuracy with a maximum resistance up to 3 TΩ.  All units are rated for use at an altitude of 3,000 meters and still maintain CAT IV 600 V safety rating.


The MIT525, MIT1025 and MIT1525 perform spot tests, step voltage tests, dielectric discharge tests, ramp tests and dielectric absorption tests for QA testing in manufacturing processes, diagnostic testing to isolate faulty components for repair as well as routine preventative/predictive maintenance testing after an installation.


These lightweight, compact insulation testers feature a lithium-ion battery that can test continuously for up to six hours on one single battery charge.  The units are designed to charge while operating and continue to take measurements when connected to line power with a fully discharged battery.  This ensures an optimal charge that results in minimal charge times. 


All of the MIT models are capable of delivering short circuit current with Megger's unique max power regulation technology. This ensures maximum power transfer at 3 mA, no matter what the load is, until the desired test voltage is reached. For more details, go to