SmartPLC SafeLine AC4S with fieldbus interfaces
260
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SF_IN_local_dependent_filter_nshutdown
43094
Device type:
Local I/O interface (input)
Library:
sf_logicalinterfaces.library
Symbol in CODESYS:
>
Description
43308
Logical device for a safe sensor with 2 interdependently acting contacts/channels
SF_IN_local_dependent_filter_nshutdown detects the switching states of the two input channels of the
local I/O interface (IN_Channel_A, IN_Channel_B). The logical device forms the logical AND
connector from the two values and provides the result as safe control signal. The following additional
conditions apply for the logical signal evaluation:
The contacts/channels are debounced during switch-on: Signal changes that are applied shorter
than the set stabilisation time do not lead to a change in state. (StabilisingTime)
Simultaneity of the signal change of the two contacts/channels is monitored during switch-on: If
the signal states are not equal for a longer time than the set synchronisation time, both
contacts/channels have to take the value FALSE simultaneously before switch-on is possible
again. (SynchTime)
If both contacts/channels take the value TRUE again during the switch-off process, switch-on
occurs at once. When the tolerance time has elapsed, the two contacts/channels have to take the
value FALSE again simultaneously before switch-on is possible again. (ToleranceTime)
If after the start the two contacts/channels do not take a valid signal state within a firmly set time,
the logical device changes to the locked error state. (InvalidTime = const. = 140ms)
The programmer can activate the following functions as option:
EnableIN_Test:
A test signal for cross-fault monitoring generated at a local output channel at the local I/O interface
is evaluated.
StartupTest:
Both signal channels must take the state FALSE simultaneously before the logical device can start
with the signal evaluation.
DisableLogging:
Only error events are transmitted to the online support centre (OSC) of the AC4S user interface.
If cross-fault detection is activated for 2-channel safe devices at the local I/O interface
(EnableIN_Test = TRUE), the following applies:
Signal change at the inputs (IN_Channel_A, IN_Channel_B) must be applied longer than the
cycle time of the test pulses (3 PLC cycles). Otherwise the logical device changes to the
locked error state.
When this logical device is used, the process safety time (PST) of the system is extended by
one cycle time of the fail-safe PLC.
► Note the remarks about process safety time (→ Device manual,
Process safety time
)!
► Observe the set cycle time of the fail-safe PLC (→
Set cycle time of the fail-safe PLC
(
To reset the logical device from the locked error state and to read diagnostic information of the
logical device:
→
CtrlLocalInputs
(
