Development of multi-channel automatic digital multimeter calibration device

The automatic detection of hand-held digital multimeter has always been a difficult problem in the field of electrical metrology due to the lack of corresponding programmable interface. In this paper, a multi-channel automatic detection device for digital multimeter is developed, which can simultaneously calibrate seven different types of digital multimeter. Taking DC voltage as an example, the results of calibration using the former calibration method are compared with those after using the device. The results show that the developed device can meet the daily calibration of hand-held digital multimeter and ensure the calibration. On the premise of accuracy, the efficiency is increased by 70%.