Functions and features With special aluminum alloy housing, the device has firm and nice appearance. It is easy to operate and transport with light weight. Single phase power supply is convenient for users with various occasions. It has multiple protection system with high speed response, that makes the device more reliable. Also it has sound and light warning unit.test Constant calibration Reading meter display data arbitrarily Meter serial number reading and inspection Various password and code verification and setting Main technical specification 1. Power supply: ~220V/16¡À10%,50HZ 2. Device class: 0.03; 0.05; 0.1 3. Voltage measuring range: 3¡Á(100/3,100,220,380)V 4. Current measuring