By executing a special test program, the corresponding signal is input during the execution process, and the state of the system operation is observed. When the code of the output signal is executed, the state of the LED is observed to determine the state of the output signal. When this function is canceled, the LED changes from light to off, so it can be determined whether the output interface of the signal is valid by observing whether the LED is bright. When executing the code, the system waits for the input signal, and after the test inputs the corresponding tool position signal to the system, the system continues to execute the following program, otherwise it waits for the external input signal until the alarm; other input signals observe the system diagnostic information. Therefore, the tester must concentrate on observing the signals and providing corresponding input signals, and judge whether the corresponding 809 interface is normal. This method is particularly inefficient and has the possibility of error. The system has a macro program function, and each input/output port has an independent macro variable value. Therefore, it is considered that the macro program can assign a value to the input/output port or detect the state of the variable, thereby realizing the system automatic detection function. During the test, the tester only needs to connect the input and output ports with the test connection, and enter and execute the test macro program to automatically complete the system detection. Hardware Elements This design solution has low hardware requirements. It only needs to connect the input and output interfaces to the supporting test racks. The supporting test stand is mainly composed of photoelectric isolators, resistors and diodes. Compared with other test stands, the test stand only acts as a connection signal during the test. The test process does not require the tester to observe and provide input signals on one side. When the test program is started, the system automatically performs the test, and the tester only needs to observe whether the system is executed. When the system does not generate any alarm signal, the system is qualified; when an alarm signal is generated, the system can be placed in the non-conforming area, and then the next system is tested. Such a person can test multiple systems at the same time, which greatly improves production efficiency. The input signal is connected in one-to-one correspondence with the output signal. Each output signal is combined with an input signal. Each output signal is connected to a light-emitting diode. In the event of a fault, only the output signal needs to be valid. If the LED is illuminated, the input signal connected to the output signal is open; if the LED is not lit, the output signal is output. open circuit. At this point, according to the result of the inspection, the end position of the fault can be directly determined, and then the fault is located in the reverse direction according to the route direction, thereby handling the fault. When the output port is assigned, the output port is valid. At this time, the output port is low. When the value is assigned, the output port is invalid. At this time, the output port is high. When one of the signals is not detected, the input and output signals of the group are checked according to the alarm information, and then the two signals are specifically tested to determine which signal is a problem. The execution time of the macro is very short, so the execution of the program is very fast, and when the method is tested, the execution time can be shortened as much as possible, and the test speed can be improved. When testing by this method, the requirements of the tester are not high. The tester only needs to connect the input and output interfaces with the test connection to execute the program. In the event of a fault, the system automatically generates an alarm signal and performs a maintenance test. Therefore, one tester can test multiple systems at the same time, which can greatly improve efficiency and reduce unnecessary losses caused by personnel negligence. (Finish) Nantong Weizhuo Environmental Protection Equipment Co.,Ltd , https://www.cwz-floorscrubber.com