schmersal PSC1 Series Installation Manual page 44

Installation manual
For the safety-related assessment of the overall system, it is therefore possible in principle to
use the following diagnostics for the input sensors:
Characteristic Tests that can be
s of the input configured / operative
element
Single-channel
X
X
Dual-channel
X
HB-37350-810-01-38F-DE PSC1-C-10 Installation manual V1.1.docx
Version: 38F
DC
tests
O O >60
90
O O 90-99
90
O O 90-99
99
X 99
Definition of the
measure
Cyclic test pulse by means of
dynamic change in the input
signals
Cyclic test pulse by means of
dynamic change in the input
signals
Cyclic test pulse by means of
dynamic change in the input
signals
Cross comparison of input
signals with dynamic test, if
short-circuits cannot be
detected (with multiple
inputs/outputs)
Cyclic test pulse by means of
dynamic change in the input
signals
Cross comparison of input
signals with immediate and
intermediate results in the
logic (L) and program
execution monitoring in
relation to timing and logic,
and detection of static failures
and short-circuits (with multiple
inputs/outputs)
Plausibility check, e.g. usage
of normally open contacts and
normally closed contacts =
antivalent signal comparison of
input elements
Comment
An adequately high
test rate must be
ensured
Only effective if pulse
allocation active
DC dependent on
frequency of the start
/ cyclic test
DC = 90 test only at
intervals > 4 weeks
DC = 99 test at least
1 x day/ or 100-times
demand rate
With short-circuit fault
exclusion up to
DC=99 possible
DC dependent on
frequency of the start
/ cyclic test
Only effective if pulse
allocation active
Only effective in
conjunction with
activated time
monitoring function
for input element
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