PACMotion™ PSD
Installation and User Manual
Section 4
GFK-3168A
September 2020
Technical Description and Data
42
4.16.9.4
Dual Channel control, SIL CL3 / PLe
To achieve PLe / SIL CL3, the safe switching of the pulse inhibitor must be tested peri- odically by
analyzing the feedback signal from a safety control:
•
at the start of a system,
•
at the restart after triggering a protective device, at least every 8 hours by the operator.
The inputs STO-ENABLE 1 and STO-ENABLE 2 are switched in turns according to a defined test
sequence. The switching state of the pulse inhibitor is available at the STO-Status outputs of the
PSD and must be analyzed to achieve a sufficient diagnostic cover ratio:
•
Diagnostic with external not safe controller, test with dynamic sequence: test cycle: with
each device start, minimum once per day.
o
diagnostic cover ratio: 60 %
•
Diagnostic with external safe controller, test with dynamic sequence. test cycle: with each
device start, minimum once per day.
o
diagnostic cover ratio: 90 %
The test sequence for the functional test of the safe pulse inhibitor must be performed as shown in
the following time diagram.
Start conditions of the test sequence:
•
O
perational readiness FAULT = “1"
•
Enable signal
ENABLE = “0
"
•
STO-
ENABLE 1 = “0"
•
STO-
ENABLE 2 = “0"
Figure 13:
Dual Channel control, SIL CL3 / PLe
