The Megohmmeter Model 1040 is a battery-powered digital insulation resistance tester. It is designed to measure insulation resistance, continuity, and voltage and to measure resistance. The Model 1040 tests are 500 and 1000V. It incorporates a 600V voltmeter which automatically detects and accurately displays AC/DC voltages in the test circuit on each of the insulation test voltage ranges. Above 25V it also provides an audible and visual signal and inhibits further tests, thus protecting the user and the meter.