High accurate and stable digital bench type multimeter with a 24 bit A/D converter, controlled by a single-chip computer. It can operate 10 measurement functions, not only DC, AC, rms, but DC and AC mixture signals RMS can measured for 1000 V or 10 A. The resolution of DCV is 1 µV and the frequency band of voltage or current is about 20 kHz. The multimeter is also a frequency counter, which can test pulse frequency over 2 MHz or linear frequency more than 200 kHz, including the frequency current. The measurement of 50 MΩ, resistor 5000 µF capacitor, maximum/minimum, averrage, relative value, power dB, diode continuity and memory function up to 30 full screen for saving data are useful for engineers. This bench type multimeter is controlled and calibrated by software, so that it’s stability for long time is guaranteed.
 
With the optical USB-interface and computer software the unit can display, draw record all test processes on a computer, the graphic software has an exclusive dynamic scale, which can describe very small changes of electric parameters. In connection with a computer the bench type multimeter becomes a very useful measurement recorder and the protection functions against some error operations get it’s safety characteristic guaranteed.