Siemens PLC shutdown software reasons summary - Database & Sql Blog Articles

RF cable can be customized for other specifications

Programmable Package SG-8018CA(SG7050C) 0.67M~170M

There are many cases where cpu is put into stop, such as address call error, no DB block required for download, programming error, etc. If you want to avoid the error and do not make the CPU enter the stop state, you can add special OB block in the program, then it will appear. Corresponding problem, the corresponding OB block is called. Although there is no program inside, plc will not process any error errors and continue to run. Otherwise the PLC will enter a shutdown state, such as:
OB73 communication redundancy error OB
When the first redundancy loss occurs in a fault-tolerant S7 connection, the H CPU's operating system calls OB73 (only fault-tolerant S7 connections are available in S7 communication. For more information, see "S7-400 H PLC, Fault Tolerance" system."). If redundancy is lost in other fault-tolerant S7 connections, there will be no more OB73 startup. Another OB73 boot will not occur until redundancy is restored for all S7 connections with fault tolerance. If a start event occurs and OB73 is not programmed, the CPU will not switch to STOP mode.
OB80 time error organization block The operating system of the S7-300 CPU calls OB80 whenever an error occurs while executing the OB. Such errors include:
When the cycle time is exceeded, a confirmation error occurs when the OB is executed, and the start time of the OB is skipped before the time is advanced.
Restore RUN mode after CiR. For example, if the start event of a cyclic interrupt OB occurs after the last call and the same OB is still executing, the operating system will call OB80. If OB80 has not been programmed, the CPU will change to STOP mode. The time error OB can be disabled or delayed and re-enabled with SFCs 39 to 42.
The OB81 power supply organization block is only involved in an event triggered by an error or fault that is related to the power supply (only on the S7-400) or the backup battery (when events enter and leave), then the S7-300 CPU The operating system calls OB81. In the S7-400, if the battery test function has been activated using the BATT.INDIC switch, OB81 will only be called in the event of a battery fault. If OB81 is not programmed, the CPU will not switch to STOP mode. You can disable or delay with SFC 39 to 42 and re-enable the power error OB.
The OB82 diagnostic interrupt organization block detects an error if a module with diagnostics (for which diagnostic interrupts have been enabled) outputs a request for a diagnostic interrupt to the CPU (when events enter and leave). Then the operating system calls OB82. The local variables of OB82 contain the logical base address and the diagnostic data of the four-byte faulty module (see table below). If OB82 has not been programmed, the CPU goes to STOP mode. You can disable or delay with SFC 39 to 42 and re-enable the diagnostic interrupt OB.
OB83 Insert/Delete Module Interrupt Organization Block The CPU operating system calls OB 83 under the following conditions:
? After inserting/deleting a configured module
You can disable/delay/enable the insert/delete interrupt OB with SFC 39 to 42 after you have modified the module parameters in STEP 7 and downloaded the changes to the CPU during runtime.
OB84CPU hardware failure organization block In the following cases, the OS in the CPU will call OB84:
? After detecting and correcting a memory error
• For S7-400H: If the performance of the redundant link between the two CPUs is degraded, you can use SFC 39 to 42 to disable or delay the CPU hardware error OB and then enable it again.
The OB85 priority error organization block calls the OB85 as soon as one of the following events occurs:
• Start event of an OB that has not been loaded (except OB81).
• An error occurred while the operating system was accessing the module.
• An I/O access error occurred during the system update process image (if the configuration of OB85 is not disabled for configuration reasons).
OB86 rack fault organization block as long as the central expansion rack (without S7-300), DP master system or station fault (in case of event and departure events) is detected in the distributed I/O (PROFIBUS DP or PROFInet IO) The CPU's operating system calls OB86. If OB86 has not been programmed, the CPU will switch to STOP mode when this type of error is detected. You can disable or delay with SFC 39 to 42 and re-enable OB86.
The OB87 communication error organization block will call OB87 as long as an event caused by a communication error occurs.
If OB87 has not been programmed, the CPU will not switch to STOP mode. You can disable or delay with SFC 39 to 42 and re-enable the communication error OB.
OB 88 processing interrupt OB
After the block execution is aborted, the CPU operating system calls OB 88. The cause of this interruption may be:
• Nesting depth of synchronization error is too large
• The nesting depth of the block call (U stack) is too large
• Error when assigning local data If OB 88 is not programmed and block execution is aborted, the CPU enters STOP mode
(Event ID W#16#4570). If the block execution is aborted under priority 28, the CPU enters STOP mode. The processing interrupt OB can be disabled, delayed and enabled with the aid of SFCs 39 to 42.
OB121 programming error organization block As long as an event caused by an error related to program processing occurs, the operating system of the CPU calls OB121. For example, if the user program calls a block that has not been loaded into the CPU, OB121 will be called.
The OB122I/O access error organization block calls OB122 only when an error occurs while accessing the data on the module. For example, if the CPU detects a read error while accessing data on the I/O module, the operating system will call OB122.