A H 5 0 0 O p e r a t i o n Ma n u a l1 2 - 212.1 Troubleshooting12.1.1 Basic InspectionThis chapter describes errors which occur when a system operates, reasons for these errors, and remedies.Before eliminating an error, users have to determine the reason for the error. Before determining the reason,the users have to check the following.(1) The following items have to be checked. The PLC system must operate under the conditions which are regulated, e.g. the environment, theelectrical condition, the mechanical vibration, and etc. The power is supplied to the power supply module properly, and the power supplied to the PLCsystem is normal. The backplanes, modules, terminals, and cables are installed properly. Every LED indicator is in a normal state. The setting of the switches is correct.(2) Follow the instructions below, and check the operating state of the AH500 system. Turn the RUN/STOP switch. Check the condition for the running/stopping of the CPU module. Check and eliminate the influences that the external devices may cause. Monitor the operating state of the system and the error logs by means of ISPSoft.(3) Determine the reason for the error according to (1) and (2) above. The AH500 system or the external devices The CPU module or the extension modules The parameters or the control programs12.1.2 Eliminating ErrorsIf an error occurs in a system, users can try to eliminate the error in the following ways. If the reason for theerror still exists after the error is eliminate, the error will occur in the system again.(1) Stop the CPU module, and then run it.(2) Disconnect the CPU module, and then connect it.(3) Clear the error log by means of ISPSoft.(4) After the CPU module is rest, or restored to the factory setting, download the program again, and executethe program.