This device adopts advance ARM+FPGA high precision D/A conversion and DDS technologies can set up and regulate parameters of voltage current frequency phase etc in a long period of time via analog closed loop feedback and digital PID control 1. Can be used to test errors and variance caused by voltage current waveform or power factor change for a variety of metering instrument such as energy meter voltmeter ammeter wattmeter frequency meter power factor meter phase meter 2. Can generate distorted wave with 2~32 order harmonic harmonic number order amplitude and phase position to base wave can be controlled by programs 3. Operational amplifier work frequency 40HZ~1kHz good linearity dual output protection High fidelity output signal and high shock-proof ability 4. With RS232 and USB(optional) communication interface for PC connection 5. With aluminum alloy carrying box which look nice and with little weight