Research on the Reliability Test Device of Thermal Overload Relay

摘要

Taking the success rate as the reliability index of the overload protection and based on the reliability test method, the reliability test device of thermal overload relay is designed. The design includes two parts, the hardware design and the software design. The hardware design mainly includes the design of the main test circuit, the signal sampling and processing circuits and control signal input and output circuit .In order to processing and analyzing the data quickly and accurately , PCL-818L which has high performance is used to control the collection of voltage and current , and PCL-720 which is an I/O control card is used to detecting the status of the auxiliary contactor and detecting whether the circuit is closed. The software design mainly includes the programming of software interface, parameters setting module, current measurement module, steady flow control module, parameters and results viewer module, the test running module and so on. The test device is controlled by the industrial computer and the program is developed by VB6.0 under the WindowsXP system, The control precision and automatic degree are enhanced evidently.