Flowserve 500+ Series Logix - Manual (Page 44)

User Instructions - Logix® 500+ Series Digital Positioners FCD LGENIM0105-10 11/13
flowserve.com 44
The following tests need to be specifically executed when a
proof test is performed. The results of the proof test need to
be documented and this documentation should be part of a
plant safety management system.
NOTE: Positioner failures that are detected should be
reported to Flowserve.
To perform the proof testing, an LCD display or HART
communicator such as a 375 Handheld or software such as
ValveSight DTM for Logix 520MD+ are required.
Steps for Proof Test
Step Action
1. Bypass the safety PLC or take other appropriate action to
avoid a false trip.
2. Set the analog input command to less than 3.6 mA.
3. Ensure that the attached valve is fully in the safe state
(defined by application) and has moved to that position
within the allowed time. This will test for all failures that
could prevent the closure of the valve, including electronic
and mechanical faults, as well as valve faults.
4. Inspect the 520MD+ Valve Positioner for any visible
damage or contamination and ensure the follower arm has
sufficient spring bias if applicable.
5. Check the errors generated by accessing the Alerts and
Alarms menu on the LCD or the Alarm Annunciator in the
DTM or other HART system using command 48.
6. Remove the bypass from the safety PLC or otherwise
restore normal operation.
When the tests listed above are executed, a proof test
coverage of 95% for the 520MD+ can be claimed if PST has
not been implemented as a diagnostic. To be considered as
a diagnostic the PST has to be implemented in a SIL rated
logic solver. If PST has been implemented, then no additional
failure modes will be detected by the proof test. Failure
modes not covered include possible leaking of the valve seat
for fail closed valves.
Steps for Partial Stroke Test (PST)
Step Action
1. Verify the control loop is ready for valve movement in the
amount set for the PST.
2. Execute the PST via the LCD menu, DD, or DTM.
3. View the results of the PST via the LCD menu, DD, or
DTM.
4. Check the errors generated by accessing the Alerts and
Alarms menu on the LCD menu, DD, or the Alarm
Annunciator in the DTM or other HART system using
command 48.
When the tests listed above are executed, a proof test
coverage of 95% for the 520MD+ can be claimed if PST has
not been implemented as a diagnostic. To be considered as
a diagnostic the PST has to be implemented in a SIL rated
logic solver. If PST has been implemented then no additional
failure modes will be detected by the proof test. Failure
modes not covered include possible valve sticking in the
travel range not tested and leaking of the valve seat for fail
closed valves.
16.11 Maintenance
Follow routine maintenance. See section 17.1 Scheduled
Maintenance.
16.12 Repair and replacement
In the unlikely event that the Flowserve 520MD+ Valve
Positioner fails, the failure should be reported to Flowserve.
Replace faulty components according to section 17 of this
manual or return the positioner to Flowserve for service.
With experience and the right parts, repair times for any
component can be less than an hour, however a 24 hour
mean time to repair should be assumed for safety availability
calculations.
16.13 Training Requirements
Activities specified in this manual shall be performed by a
service technician trained in the installation and maintenance
of process instrumentation. See section 1.4 Qualified
Personnel.