The Megger® BM120 Series of Digital Insulation and Continuity Testers offers a cost effective solution to testing where only basic test facilities are required. Instruments are available with single insulation test voltages of 500V DC or 1000 V DC. and test results are displayed on a clear 3-digit autoranging liquid crystal display. Full rated test voltage is produced when supplying up to 1 mA load.

Both instruments offer hands free continuity measurement with a short circuit current of greater than 200mA and an open circuit voltage of 5 V. If either instrument is connected to a system which is energized to greater than 25 V, a warning symbol on the display will flash. Under this condition an insulation or continuity test cannot be carried out and the instrument will therefore automatically inhibit any further action until the source of voltage has been removed.

Although insulation tests should only be carried out on de-energized systems, the instruments are protected against accidental connection to phase to earth voltages up to 300 V AC and phase to phase voltages of 440 V AC, Installation Category III. Further indicators illuminate to show a low battery state and if the protective fuse has ruptured. The instruments will automatically shut down after 5 minutes of non use.