Siemens SIMATIC S7-400H System Manual page 54

Assembly of a CPU 41x–H
5.2 Monitoring functions of the CPU
Type of error Cause of error
Execution The execution of a program block was
canceled canceled. Possible reasons for the
cancellation are:
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Programming User program error:
error
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MC7 code error Error in the compiled user program, for
example, illegal OP code or a jump beyond
block end
54
Nesting depth of nesting levels too great
Nesting depth of master control relay too
great
Nesting depth of synchronization errors
too great
Nesting depth of block call commands (U
stack) too great
Nesting depth of block call commands (B
stack) too great
Error during allocation of local data
BCD conversion error
Range length error
Range error
Alignment error
Write error
Timer number error
Counter number error
Block number error
Block not loaded
Response of the operating system
Call of OB 88
If the OB is not loaded: CPU changes
to STOP mode.
Call of OB 121
If the OB is not loaded: CPU changes
to STOP mode.
CPU changes to STOP mode.
Restart or memory reset required.
System Manual, 03/2012, A5E00267695-11
Error LED
INTF
INTF
INTF
S7-400H