Woodward Large Electric Sonic Valve II, Installation And Operation Manual, Page: 54 / 66

Manual 35076 LESV II
Woodward 52
Functional Testing after Initial Installation
A functional test of the LESV is required prior to use in a safety system. This should be done as part of
the overall safety system installation check and should include all I/O interfaces to and from the LESV.
For guidance on the functional test, see the Proof Test procedure below.
Functional Testing after Changes
A functional test of the LESV is required after making any changes that affect the safety system. Although
there are functions in the LESV that are not directly safety related, it is recommended that a functional
test be performed after any change.
Proof Test (Functional Test)
The LESV must be periodically proof tested to ensure there are no dangerous faults present that are not
detected by on-line diagnostics. This proof test should be performed at least once per year.
Suggested Proof Test
The suggested proof test consists of a full stroke of the valve, shown in the table below.
Table 6-2. Suggested Proof Test
Step Action
1. Bypass the safety function and take appropriate action to avoid a false trip.
2. Interrupt or change the signal/supply to the actuator to force the actuator and valve to the Fail-
Safe state and confirm that the Safe State was achieved and within the correct time.
3. Re-store the supply/signal to the actuator and inspect for any visible damage or contamination
and confirm that the normal operating state was achieved.
4. Inspect the valve for any leaks, visible damage, or contamination.
5. Remove the bypass and otherwise restore normal operation.
For the test to be effective, the movement of the valve must be confirmed. To confirm the effectiveness of
the test both the travel of the valve and slew rate must be monitored and compared to expected results to
validate the testing.
Proof Test Coverage
The Proof Test Coverage for the LESV is given in the table below.
Table 6-3. Proof Test Coverage
Application Safety Function
λ
DU
PT
6
Proof Test Coverage
No PVST with PVST
Clean Service Close on Trip – Full Stroke 272 67% 40%
The suggested proof test and proof test coverage is referenced in the product FMEDA; WOO 17/07-039
R001.
Released