Design and application of the automatic test syste

Design and application of automatic test system of main board of thermal relay tester

the new method of main board test of thermal relay tester can accurately, quickly and comprehensively detect the product quality problems of main CPU board in the production process. The software and hardware design of automatic test system of main board of relay protection device are introduced in detail. Finally, the practical application of the test system is introduced:

in recent years, the development of power system requires higher and higher reliability of the hardware system of thermal relay tester. How to ensure the quality of the hardware system is an urgent problem to be solved. The main board of the thermal relay tester is the core of the whole protection device. Most of the main CPU boards are the whole set of computer systems, data acquisition, input and output of switching values, etc. concentrated in this printed board. Traditional manual testing, on the one hand, is inefficient, on the other hand, it is difficult to comprehensively and scientifically detect the quality problems existing in the main board of the thermal relay tester. With the rapid development of computer technology and communication technology, the automatic test technology with computer as the test and control center is becoming more and more perfect, and has been widely used in many fields

the automatic test system proposed in this paper is designed for the main CPU board of the 800 series thermal relay tester, the mainstream product of XJ company. The CPU board takes the 32-bit TMS320C32 DSP chip produced by TI company as the core. The hardware circuit composition mainly includes: CPU, memory, data acquisition circuit, switch input and output circuit, communication circuit, frequency measurement circuit, hardware watchdog, etc. the test system mainly takes these hardware circuits as the test objectives. The automatic testing system can accurately and comprehensively complete the testing tasks that are difficult to be completed by manual testing, improve the testing efficiency and ensure the product quality

for example, the section from the midpoint of the graph to the point is the hardware composition and working principle of the test system in the strengthening stage.

the main board automatic test system is mainly composed of a control platform (PC) and a test device. The control platform is mainly composed of PC, analog output card (D/a card), switch input and output card, multi serial communication card, etc. The test device is mainly composed of power plug-in, auxiliary test plug-in, i-bay 4 test machine box with the arrival of lighting replacement period, tested motherboard, etc. Each output of the analog output card of the control platform is connected to the data acquisition circuit of the tested motherboard, and each output of the switch output card of the control platform is connected to the switch input circuit of the tested motherboard. Each output of the switch input card of the control platform is connected to the switch output circuit of the tested motherboard; The control software controls the analog output card to output AC voltage, which is applied to the data acquisition circuit of the tested motherboard of the test device. The tested motherboard is durable and transmits the collected data to the PC through the serial port communication circuit. The PC intelligently analyzes and compares the collected data to judge whether each data acquisition circuit is qualified. The switch output card of PC is correspondingly connected to the input circuit of the tested motherboard integrating the above technologies, and the excitation quantity is applied to the tested motherboard by controlling the output of the switch output card, and the read back input quantity data is transmitted to PC machine through serial communication by the tested motherboard. Judge whether the input circuit is qualified

the thermal relay tester system adopts a distributed structure, so that the work of the system is distributed to the control platform (upper computer) and the tested main board (lower computer) of the test device, which helps to realize the real-time data acquisition and processing of signals and the rapid response performance of the system. The whole process constitutes a closed-loop test

the upper computer mainly completes communication, sends test commands, statistical analysis of measured point data, display function, sorting and printing of test reports, etc; The lower computer mainly completes the functions of responding to test commands and sending test data