© exida.com GmbH TURCK 04-07-14 R001 V2R0.doc; February 8, 2013
Stephan Aschenbrenner Page 24 of 25
Analog Signal Transmitter
Proof test 1 consists of the following steps, as described in Table 9.
Table 11 Steps for Proof Test 1
Step Action
1 Take appropriate action to avoid a false trip
2 Provide a 4mA control signal to the Analog Signal Transmitter to open/close the
valve and verify that the valve is open/closed.
This tests for compliance voltage problems such as a low loop power supply voltage or
increased wiring resistance. This also tests for other possible failures.
It requires, however, that the valve has already been tested without the Analog Signal
Transmitter and does not contain any dangerous undetected faults anymore.
3 Restore the loop to full operation
4 Restore normal operation
This test will detect approximately 70% of possible “du” failures in the Analog Signal
Transmitter.
Proof test 2 consists of the following steps, as described in Table 10.
Table 12 Steps for Proof Test 2
Step Action
1 Take appropriate action to avoid a false trip
2 Perform Proof Test 1
3 Provide a 4..20 mA control signal in steps of 1 mA to the Analog Signal Transmitter
to open/close the valve and verify that the valve opens/closes accordingly.
This requires that the valve has already been tested without the repeater and does not contain any
dangerous undetected faults anymore.
4 Restore the loop to full operation
5 Restore normal operation
This test will detect approximately 95% of possible “du” failures in the Analog Signal
Transmitter.
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