Function: 1. AC and DC voltage measurement; 2. Insulation resistance measurement; 3. 100 groups of data storage; 4. Automatic calculation of polarization index, absorption ratio; 5. Backlight and data retention function; Specification: Size: 172.7 x 140.3 x 62.3mm / 6.8 x 5.5 x 2.5in Power supply: 8*AA batteries (not included) Maximum display: 2000 counts Measuring range: 1. Measure the output voltage MH12: 50V-1000V, (50V, 100V, 250V, 500V, 1000V,). 2. Measure insulation resistance: MH12: 0.1MΩ-10GΩ. Absorption ratio and polarization index standard Absorption ratio DAR: The ratio of the insulation resistance value at 1 minute to the insulation resistance value at 30 seconds. Polarization index PI: The ratio of the insulation resistance value at 10 minutes to the insulation resistance value at 1 minute, to judge whether the equipment has affected the insulation resistance due to moisture Insulating materials all have the absorption process and polarization process of charge after adding high voltage. The power system requires that the polarization index should be measured in the insulation test of the main transformer, cable, motor, etc., and this data can be used to judge the quality of the insulation, quality and aging problems. Material: ABS colour: Red+black Package Contents: 1 x Digital Megohmmeter 1 x english manual