Masoneilan SVI II ESD, Руководство по установке и обслуживанию

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Proof Test
You can also manually run a proof test. The objective of proof testing is to detect failures
within an SVI II ESD and ESD valve that are not detected by any automatic diagnostic of the
system. Of main concern are undetected failures that prevent the safety instrumented
function from performing its intended function.
Proof testing frequency or proof test interval, has to be determined in reliability calculations
for the safety instrumented functions to which SVI II ESD is applied. The proof tests must be
performed more frequently or as frequently as specified in the calculation in order to maintain
the required safety integrity of the safety instrumented function.
The following proof test is recommended. Report any detected failures that compromise
functional safety to the factory.
This test detects approximately 99% of possible DU failures in the SVI II ESD (Proof Test
Coverage).
The person (s) performing the proof test of an SVI II ESD must be trained in SIS operations,
including bypass procedures, maintenance and company Management of Change
procedures. No special tools are required.
Table 1 Proof Test Steps
Step
Action
1
Read the SVI II ESD data record using a HART
®
handheld device or ValVue ESD software. Solve any active
faults before proceeding.
2
Bypass the valve, or isolate or take other appropriate action to avoid a false trip, following company Man-
agement of Change (MOC) procedures
3 Inspect the SVI II ESD for dirty or clogged ports and other physical damage
4
De-energize the SVI II ESD and observe that the actuator and valve move. Energize the SVI II ESD after the
valve has moved to its full stroke length. An accumulated value of 100% travel = 1 stroke. The travel does
not need to occur in one movement.
5
Inspect the SVI II ESD for dirt, corrosion or excessive moisture. Clean if necessary and take corrective
action to properly clean the air supply. It has to be done in order to avoid incipient failures due to dirty air.
6 Record any failures in your company’s SIF inspection database. Restore the loop to full operation.
7 Remove bypass or otherwise restore normal operation