4.4.5.1
Static control inputs
Overview
The static control inputs support the following evaluation methods:
•
Complementary analysis
•
1-of-n-evaluation
You can define the switching criteria for the monitoring cases (
).
Complementary analysis
A static control input consists of 2 channels. To switch correctly, one channel must be
switched inversely to the other. The following table shows which status the static control
input’s channels must have to define logical input condition 1 and 0 at the relevant
control input.
Table 3: Status of the channels of the control inputs with complementary evaluation
A1
A2
Logical input status (input A)
1
0
0
0
1
1
1
1
Fault
0
0
Fault
In antivalent evaluation, the 2 channels of each static control input must always be
inverted, even if the status of a control input in a monitoring case is random. If it is not
inverted, all safety outputs switch to the OFF state and the device displays a fault.
1-of-n evaluation
With the 1-out-of-n evaluation, each channel of a control input is considered individu‐
ally. At any time, exactly one channel must have logic value 1.
Table 4: True vales with 1-off-n-evaluation with 2 input pairs (example)
A1
A2
B1
B2
Result (e.g. monitoring case no.)
1
0
0
0
1
0
1
0
0
2
0
0
1
0
3
0
0
0
1
4
Other input conditions
Error
Complementary information
•
When the input signal is changed, the previous monitoring case remains active for
the duration of the set switch-on delay. If no valid input signal is present after the
switch-on delay has elapsed, the behavior depends on the sequence monitoring:
°
If monitoring of the switching sequence (sequence monitoring) is not acti‐
vated, the OSSDs switch to the OFF state after the switch-on delay has
elapsed. If a valid input signal is present within another second, the safety
laser scanner activates the new monitoring case. If no valid input signal is
present within this time, the OSSDs remain in the OFF state and the safety
laser scanner displays an error and must be restarted.
°
If monitoring of the switching sequence (sequence monitoring) is activated,
the OSSDs switch to the OFF state after the switch-on delay has elapsed and
the safety laser scanner displays an error and must be restarted.
PROJECT PLANNING
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8025424/1ELL/2022-01-21 | SICK
O P E R A T I N G I N S T R U C T I O N S | microScan3 Pro I/O
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Subject to change without notice
