1. When comparing the input signal LGplc, compare the status displayed by the LGplc programmer with the LED indication of the input module. If the result is different, then we should replace the input module. If more than one module is found to be replaced, we should check the I/O extension cable and its connections before replacing it.
2. If the LGPLC signal stops moving in one place, these places are usually where the output is excited. Generally, it is in the middle state. When LGPLC is repaired, we should find the signal that causes it to happen in the next step (timer, line Chuan, input, drum controller, etc.), the programmer will display the on/off status of that signal.
3. When the LGPLC is repaired, if the input state is consistent with the LED indication of the input module, then we should compare the state of the input device (button, limit switch, etc.) with the LED. If the two are not the same, then we should measure the input module. If you find a problem and need to replace the I/O device, the site must be wired or powered; otherwise, the LGPLC needs to replace the input module.
4, LGPLC maintenance, if the signal is line, the output is different from the state of the line or no output, then you must use the programmer to check the output drive logic, and check the program list. When LGPLC is repaired, the inspection should be carried out from left to right to find the first contact that is not connected. If the one that is not connected is the input, check the input point according to the second and third steps. If it is a line Chuan, check the fourth and fifth steps. Be sure to make the master control relay not affect the logic operation.
5, LGPLC maintenance, if the signal is controlled on a counter, first check the logic of the control reset, and then check the counter signal, according to the above 2 to 5 steps, the frequency frequency setting of several methods are: analog Input settings, fixed frequency settings, communication input settings, .
6. When the LGPLC is repairing, if the signal is a timer and it stops at a non-zero value less than 999.9, then the CPU module must be replaced.
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