Runtimes Of The Fcs And Fbs For Redundant I/Os - Siemens SIMATIC S7-400H System Manual

Technical data

17.5 Runtimes of the FCs and FBs for redundant I/Os

17.5 Runtimes of the FCs and FBs for redundant I/Os
Table 17-1 Runtimes of the blocks for redundant I/Os
Block Runtime in stand-alone/single mode
FC 450 RED_INIT 2 ms + 300 µs / configured module pairs
Specifications are The specification for a module pair is a mean
based on the startup value. The runtime may be < 300 µs for a few
modules. For a large number of redundant
modules the value may be > 300 µs.
FC 451 RED_DEPA 160 µs
FB 450 RED_IN 750 μs + 60 μs / module pair of the current TPA
Called from the The specification for a module pair is a mean
corresponding value.
sequence level
The runtime may be additionally increased if
discrepancies occur resulting in passivation and
logging to the diagnostics buffer.
The runtime may also be increased by a
depassivation carried out at the individual
sequence levels of FB RED_IN. Depending on
the number of modules in the sequence level,
the depassivation may increase the runtime of
the FB RED_IN by 0.4 ... 8 ms.
An 8 ms increase can be expected in redundant
operation of modules totaling more than 370
pairs of modules at a sequence level.
FB 451 RED_OUT 650 μs +2 μs / module pair of the current TPA
Called from the The specification for a module pair is a mean
corresponding value. The runtime may be < 2 µs for a few
sequence level modules. For a large number of redundant
modules the value may be > 2 µs.
FB 452 RED_DIAG Called in OB 72: 160 µs
Called in OB 82, 83, 85:
250 µs + 5 µs / configured module pairs
Under extreme conditions the runtime of FB
RED_DIAG is increased up to 1.5 ms. .
This is the case when the working DB is 60 KB or
larger and if there are interrupt trigger addresses
that do not belong to the redundant I/O.
FB 453 160 μs + 4 μs/ configured module pairs * number
RED_STATUS of module pairs)
The runtime depends on the random position of
the module being searched for in the working DB.
When a module address is not redundant, the
entire working DB is searched. This results in
the longest runtime of FB RED_STATUS.
The number of module pairs is based either on
all inputs (DI/AI) or all outputs (DO/AO).
NOTICE
These are guide values, not absolute values. The actual value may deviate from these
specifications in some cases. This overview is intended as a guide and should help you
estimate how use of the RED_IO library may change the cycle time.
310
Runtime in redundant mode
-
360 µs
1000 μs +70 μs / module pair of the current TPA
The specification for a module pair is a mean
value.
The runtime may be additionally increased if
discrepancies occur resulting in passivation and
logging to the diagnostics buffer.
The runtime may also be increased by a
depassivation carried out at the individual
sequence levels of FB RED_IN. Depending on
the number of modules in the sequence level,
the depassivation may increase the runtime of
the FB RED_IN by 0.4 ... 8 ms.
An 8 ms increase can be expected in redundant
operation of modules totaling more than 370
pairs of modules at a sequence level.
860 μs +2 μs / module pair of the current TPA
The specification for a module pair is a mean
value. The runtime may be < 2 µs for a few
modules. For a large number of redundant
modules the value may be > 2 µs.
Called in OB 72: 360 µs
Called in OB 82, 83, 85:
430 μs (basic load) + 6 μs / configured module
pairs
Under extreme conditions the runtime of FB
RED_DIAG is increased up to 1.5 ms. .
This is the case when the working DB is 60 KB or
larger and if there are interrupt trigger addresses
that do not belong to the redundant I/O.
350 μs +5 μs/ configured module pairs * number
of module pairs)
The runtime depends on the random position of
the module being searched for in the working DB.
When a module address is not redundant, the
entire working DB is searched. This results in the
longest runtime of FB RED_STATUS.
The number of module pairs is based either on
all inputs (DI/AI) or all outputs (DO/AO).
System Manual, 09/2007, A5E00267695-03
S7-400H