Megger MJ159 Hand Crank Analog Insulation Resistance Tester - 100V to 1000V

Features & Applications:

This Megger MJ159 hand crank analog insulation resistance tester is a portable, self-contained instrument designed to give rapid and accurate measurements. It has four selectable test voltages of 100, 250, 500 and 1000 V dc, measuring insulation resistance up to 2000 M-Ohms, and an ohm range to 5000 ohms. Power is derived from a low-voltage, hand cranked generator which has been designed to be easy to turn even under full load conditions. The low-voltage generator is connected to an electronic inverter to provide a very stable test voltage. Accuracy of measurement is unaffected by variations in the generator cranking speed and the test voltage is maintained at its rated value.

As a safety feature, the ac voltage range becomes effective as soon as the instrument is connected to the circuit under test. Therefore, a warning is given that the circuit under test is not de-energized before the instrument is operated. Though calibrated for ac voltage, this range also monitors the automatic discharge feature so that after equipment having capacitance (i.e. a cable), has been tested, an indication can be given that the voltage has discharged to a level that is safe for removing the test leads. It has a guard terminal which may be used to prevent the effects of surface leakage from influencing the readings. This is achieved by diverting the leakage current through the guard terminal and away from the instrument’s measuring circuit. Each instrument is built into a strong ABS plastic case with a fold down carrying handle.

Features:

• No scale multipliers
  
• Multiple test voltages for spot and step voltage testing
  
• Guard terminal to eliminate surface leakage current

Specifications: