The field-testing instrument is made by using the newest international digital electron technical skill. To use DSP, the Digital Signal processor, as the axis to install this intelligent comprehensive automation field-testing instrument, this comes with a portable computer, operation menu suggestion. This instrument is simultaneously able to measure the value of single or 3 phase parameters as voltage, current, frequency, energy, power factor and etc. In the field, it can test the various type of energy meter, and it also can analyze harmonic and judge wiring connection. The results can be saved for a long term. The HPU-3006 can communicate with computer by RS-232 port, and save the measuring results into another computer disk. This instrument is having the features of high accuracy, good stability, small volume, easy to carry on and simple to operate; which is the perfect field testing equipment for energy measuring department and comprehensive automation test.