resistance, soil resistivity, earth voltage, AC voltage. Adopting the latest digital and micro-processing technology, precise 4-pole, 3-pole and simple 2-pole method for earth resistance measurement. Importing FFT and AFC technology, with a unique function of anti-interference capability and the ability to adapt to the environment Alarm Function Auto range and Data hold functions Specification Resistance Range 0 to 210k? Product Weight 1443g Short-circuit testing current AC 30mA max Open-circuit testing voltage AC 40V max Distance between electrodes 1m~200m can be set. Testing voltage waveform Sine wave Auxiliary earth resistance test 0.00K? ~ 30k?(100R+rC<50k?, 100R+rP<50k?) Earth voltage AC 0.00 to 750V Line voltage Measure when the voltage is below 750V AC Frequency 128Hz/111Hz/105Hz/94Hz(AFC) LCD Size 128mm"75mm Power supply DC 9V (6 Zinc-manganese dry batteries, R14S 1.5V; can continuously standby for 300hrs)