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SAFETY MANUAL SIL KFD0-RSH-1.4S.PS2
Proof Test
4
Proof Test
4.1
Proof Test Procedure
According to IEC 61508-2 a recurring proof test shall be undertaken to reveal
potential dangerous fails that are otherwise not detected by diagnostic test.
The functionality of the subsystem must be verified at periodic intervals
depending on the applied PFD
avg
in accordance with the data provided in see
chapter 2.4.
It is under the responsibility of the operator to define the type of proof test and the
interval time period.
The ancillary equipment required:
■
A digital multimeter (without special accuracy) will be used as ohmmeter
(mid range recommended) to check the relay outputs. Closed contacts are
shown with 0
Ω
(low impedance), open contacts are shown with OL
(overload/high impedance).
■
Power supply set at nominal voltage of 24 V DC
Procedure:
For the proof test five tests have to be done as shown in the following table and
pictures:
Test No. Input or Test Input
Output (mA)
1
V
test input
= 24 V DC
between terminals 10+, 11-
■
DTS output (terminals 5, 6): OL (overload)
■
ETS output (terminals 2, 3): shows 0
Ω
■
Red LED TST1 is flashing.
2
V
test input
= 24 V DC
between terminals 11-, 12+
■
DTS output (terminals 5, 6): OL (overload)
■
ETS output (terminals 2, 3): shows 0
Ω
■
Red LED TST2 is flashing.
3
V
test input
= 24 V DC
between terminals 10+, 11- and
between terminals 11-, 12+
■
DTS output (terminals 5, 6): shows 0
Ω
■
ETS output (terminals 2, 3): shows 0
Ω
■
Both red LEDs are flashing.
4
V
test input
= 0 V DC
between terminals 10+, 11- and
between terminals 11-, 12+
■
DTS output (terminals 5, 6): OL (overload)
■
ETS output (terminals 2, 3): OL (overload)
■
Both red LEDs are off.
5
V
input
= 24 V DC
between terminals 7+ and 8- and with changed
input polarity between terminals 7-, 8+
■
DTS output (terminals 5, 6): shows 0
Ω
■
ETS output (terminals 2, 3): shows 0
Ω
■
Yellow LED is on.
Table 4.1
Expected test results for a successful proof test
