Technical data

Table Of Contents
Organization Blocks
System Software for S7-300/400 System and Standard Functions - Volume 1/2
A5E00709327-01
1-45
1.22 Rack Failure Organization Block (OB86)
Description
The operating system of the CPU calls OB86 whenever the failure of a central
expansion rack (not with S7-300), a DP master system, or a station is detected in
the distributed I/Os (PROFIBUS DP or PROFINET IO) (both when entering and
outgoing event).
If OB86 has not been programmed, the CPU changes to the STOP mode when this
type of error is detected.
You can disable or delay and re-enable OB86 using SFCs 39 to 42.
Local Data for the Rack Failure OB
The following table describes the temporary (TEMP) variables for the rack failure
OB. The variable names are the default names of OB86.
Variable Type Description
OB86_EV_CLASS BYTE Event class and identifiers:
B#16#38: outgoing event
B#16#39: incoming event
OB86_FLT_ID BYTE Error code:
(possible values: B#16#C1, B#16#C2, B#16#C3,
B#16#C4, B#16#C5, B#16#C6, B#16#C7, B#16#C8,
B#16#CA, B#16#CB, B#16#CC, B#16#CD, B#16#CE)
OB86_PRIORITY BYTE Priority class; can be assigned via STEP 7 (hardware
configuration)
OB86_OB_NUMBR BYTE OB number (86)
OB86_RESERVED_1 BYTE Reserved
OB86_RESERVED_2 BYTE Reserved
OB86_MDL_ADDR WORD Depends on the error code
OB86_RACKS_FLTD Array [0 ..31]
of BOOL
Depends on the error code
OB86_DATE_TIME DATE_AND_TIME DATE_AND_TIME of day when the OB was called