Product Name: High Quality Digital Earth Ground Resistance Tester Model NO.: HM2571 Power Source: AC220V Weight: <=1.4kg Control: Manual Control Load Way: Host Type: Strength Testing Machine Relative Humidity: <= 85% Rh Maximum Power Dissipation: <=2W Trademark: GDHM Transport Package: Wooden Box with Foam Inside Specification: 220mm*200mm*105mm Origin: Hubei, China(Mainland) Product Description IntroductionThe tester abandons the traditional way of making power by artificial, uses advanced large scale integrated circuits,applies DC / AC transformation technology ,makes three side buttons, four-terminal measurement button to combine into a model of the new grounding resistance measuring instrument. The principle of the tester is to make DC into AC low-frequency constant current by the DC / AC converter inside, through the auxiliary grounding electrode C and E composition of the measured object circuit to generate AC voltage drop measured object, sent by the auxiliary grounding electrode P AC amplifier and then displayed through the detector head into the table. With magnification switch, available in three different capacity limits: 0 ~ 2Ω, 0 ~ 20Ω, 0 ~ 200Ω. Application The tester applies post and telecommunications, railway, telecommunications, mining and other sectors of the grounding resistance measurement of the various devices and the measurement of low resistance of the conductor resistance; this tester can also measure soil resistivity and ground voltage. Main features •the structure of high strength aluminum alloy case, the circuit to prevent the frequency, radio frequency interference detection method using phase-locked loop tracking and accompanied by synchronous switched capacitor filter, the instrument has good anti-jamming capability. • use of DC / AC technology will transform the low-frequency constant DC current into AC for the measurement. • Allow auxiliary grounding resistance in the 0 ~ 2KΩ (RC), 0 ~ 40KΩ (RP) between the change not affect measurement results.•No manual adjustment of the instrument balance, 3 (1 / 2)-bit LCD display, in addition to resistance measurement, it can also measure low resistance conductor resistance, soil resistivity and the AC ground voltage. • Should the test loop unreasonable header displays "1" overflow, consistent with conventional measurement practices. Technique Data 1) Operating Conditions Ambient temperature: 0 ºC ~ +45 ºC Relative humidity: ≤ 85% RH 2) Measuring range and the constant value (RMS) Resistance: 0 ~ 2Ω (10mA), 2 ~ 20Ω (10mA), 20 ~ 200Ω (1mA) Voltage: AC 0 ~ 20V 3) Measurement accuracy and resolution Accuracy: 0 ~ 0.2Ω ≤ ± 3% ± 1d 0.2Ω ~ 200Ω ≤ ± 1.5% ± 1d 1 ~ 20V ≤ ± 3% ± 1d Resolution: 0.001Ω, 0.01Ω, 0.1Ω, 0.01V4) Errors caused by auxiliary earth resistance and ground voltage measurement • Allow auxiliary grounding resistance RC (C1 and C2 between) 0 ~ 2Ω, 2 ~ 20Ω ≤ 1KΩ 20 ~ 200Ω ≤ 2KΩ RP (P1 and P2 between) <40KΩ error ≤ ± 5% • Allow to voltage (rms frequency) ≤ 5V error ≤ ± 5% 5) Powermaximum power dissipation≤ 2W DC: 8 × 1.5V (AA, R6) Battery AC: 220V/50Hz 6) Size and weight Host Size: 220mm × 200mm × 105mm Host Weight: ≤ 1.4kg