Biddle BM11 Megger 5 kV Insulation Resistance Tester

Biddle BM11 Megger 5 kV Insulation Resistance Tester
Manufacturer: Biddle / AVO
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Biddle BM11 Megger 5 kV Insulation Resistance Tester
Biddle BM11 Megger 5 kV Insulation Resistance Tester

Rent me for $200 a month

   The Megger BM11 5 kV Insulation Resistance Tester is a battery-powered, portable, high-voltage insulation tester. Test voltages of 500, 21, 2500 and 5000 volts dc are selected by a rotary switch, and resistance measurements up to 100 Gohm can be made on each voltage range. Readings are shown directly on an analog meter with a large, clear white on-black scale. As a safety feature, the BM11 will automatically act as an ac/dc voltmeter reading up to 21 volts when connected for a test. A warning indication is given before the TEST pushbutton is pressed if the circuit under test has not been de-energized.
   Additional safety features include automatic capacitive circuit discharge after test, with the discharging voltage shown on the meter, and additional back-up safety components. A guard terminal is provided to allow the effects of surface leakage in the item under test to be removed. A built-in battery check is provided and an indication of a low-power supply voltage condition is given by oscillations of the meter pointer. The BM11 also features a built-in battery charger and a lock-down TEST pushbutton for extended test periods.


  • Multiple test voltages
  • Automatic discharge of equipment under test
  • Lock-down TEST pushbutton for extended tests
  • Large direct-reading analog scale
  • Robust construction for field use

   The Megger BM11 series is designed for testing the insulation of high voltage electrical equipment and the wide voltage range also allows it to be applied to low voltage equipment. Generators, motors, transformers, cables and switchgear all require effective maintenance and the test techniques on the Megger range give valuable diagnostic information. Spot Insulation tests that are the most widely used, check on the general condition of electrical insulation, called up in most standards covering equipment design, testing, installation and maintenance. Insulation suffers from gradual steady decline, as well as occasional sudden damage; the effects of dirt, grease, moisture, vibration and chemical attack can be tracked through the recording of Polarization Index tests which remove the temperature dependence of raw Insulation Resistance measurements. For finding more localized insulation problems, the BM11 includes both Step Voltage and Dielectric Discharge tests. Step Voltage identifies local weak spots because they respond differently as the electrical stress is increased, while the Dielectric Discharge test can show up a single bad layer in multilayer insulation.

   The key to Predictive Maintenance is the trending of diagnostic tests and this is facilitated on the BM11 by the ability to use record results over time for trend analysis.