EVALUATION OF IMPEDANCE OF CABLES IN GONIOPHOTOMETRY

In a goniophotometer system, it is often unavoidable to use long cables to connect power supply, electrical measuring instrument, and the device under test (DUT). The measurement errors caused by cable impedance should not be ignored. An equivalent electrical circuit model considering the cable impedance of a typical goniophotometer is established in this paper. The measurement errors caused by the cable impedance are analysed by simulation. In DC and low frequency circuits, the cable impedance is almost resistive, while the inductive impedance of cables is significant and may lead to considerable errors when frequency is above 1 kHz in the circuits. Cable solutions in goniophotometry are introduced and recommended.

Establishment of Mathematical Model in Evaluation of Uncertainty in Indication Error Measurement Results

Taking Model DK-52 (Grade 0.05) multi-function three-phase electrical measuring instrument calibration device as an example, the paper describes how to evaluate the uncertainty in measurement result of indication errors in mathematical model.

Electrical Measurement Automated Calibration System Applied Research

In recent years, with the rapid development of electric power, the construction of a large number of substation, electrical measuring instrument and device is also increasing, accordingly, testing and calibration work is growing. The traditional calibration method has been unable to meet the actual needs of work. Combining with the practical work, and put forward a new automatic calibrating method, this paper introduces the electrical measuring instrument verification device of automatic calibration system of the working principle and system structure, and illustrates the system application.