Siemens SIMATIC PCS 7 Function Manual page 35

● User status word
● Lifebeat monitoring
● Deactivate unit
SIMATIC BATCH Interface Blocks V7.1
Function Manual, 03/2009, A5E02171101-01
The status word USER_STATUS can be set freely by other PCS7 applications. It is also
available in PCS 7 OS as QUSER_STATUS. The status can be requested by the
corresponding application programs on this OS. The status word may no be used by any
user programs.
The batch control system broadcasts a "Lifebeat" signal to all occupied IUNIT_BLOCK
blocks at intervals which can be configured within a BATCH in order to report the active
state of AS-OS communication and of the batch control to the blocks.
IUNIT_BLOCK sets AS_OS_ERR = 0 if it does not receive the "Lifebeat" signal within the
interval configured in BATCH. The user program evaluates this information in order to
respond to the missing connection to the batch control system. Output AS_OS_ERR is
reset to 1 after the connection was re-activated (and transmission of the Lifebeat" signal
has resumed).
– SP_COUNT = 0: deactivated / VA_COUNT constant 1
– SP_COUNT = 0: VA_COUNT is decremented at intervals of seconds, starting at
SP_COUNT.
The monitoring time has expired if VA_COUNT = 0, that is, there is no communication
with the PCS 7 OS or batch control.
Monitoring is restarted by calling SP_COUNT if LIFE = TRUE.
The IUNIT_BLOCK allows the directed deactivation of a unit for use by the batch control.
Input PEND_OOS (pending out of service) sets an internal trigger. BA_EN is immediately
set to 0 if the unit is not occupied. If a batch is currently occupied (OCCUPIED = 1)
IUNIT_BLOCK waits for the batch control to cancel this allocation and then sets
BA_EN = 0.
BATCH interface blocks
2.4 IUNIT_BLOCK
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