Development And Application Of AC/DC Ptc Element Automatic Test System Based On Labwindows

PTC(Positive Temperature Coefficient) component is a circuitprotection device of self-recovery with positive temperature characteristic,When there is an overcurrent, overvoltage or overtemperaturein a circuit,the resistance of PTC increases exponentially to protect the circuit. Afterthe faults are removed, the normal state is returned. PTC components arewidely used in consumer electronics, automotive electronics, powerelectronics temperature control, etc. Products are sampled to ensure thequality during the development and before the products leave the factory.There are various types of PTC products; they can be divided into DC andAC protection components by current type. They need two kinds of testsystem to test, and enormous energy is wasted during test. Developing oftest equipment covering all PTC products, with reduced energyconsumption, can be economically and environmentally beneficial.Firstly, this paper describes the PTC characteristic, parameter testingprinciples and methods, for the demand and function of the system test.Analysis of the similarities and differences between the testing parametersand functions of the two original test systems are analyzed. A solution tocombine the two system is proposed. It is a test system that covers the testof the PTC DC and AC products. After analyzing the technicalrequirements and features of the system, from the advancement, feasibility,economy and the reuse rate of instruments, energy-saving of the systemtechnology, the scheme is demonstrated, the overall program is determined and the architecture is presented.In order to complete the test of DC and AC products with one system,based on the applicability, advancement and energy-saving, a digitalAC/DC programmable control power supply is designed and studied. Asolution is proposed for larger energy consumption and incompatibleelectronic load in the test for data acquisition and control part. Theconfiguration of instrumentation and control equipment for themeasurement are re-optimized which resulted simplifying the controlsystem to improve the measurement instrumentation reuse rate. In thepaper, a part of system hardware and software are modular designed anddebugged. With the help of the original system, finally it comes true thatonly a set of test system can test the PTC DC and AC products, thedesign purpose is achieved.An automatic test system of AC and DC PTC component is developedin this paper, its technology is advanced, adaptability is powerful, it cancover the PTC DC and AC test, reducing the machine, maintenanceand test cost, through the analysis and test data on the prototype, theaccuracy and consistency of each test parameter can meet theusers’requirements, the research result is expectable.