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FAITH partial stroke

Online testing and maintenance of critical ESD valves
without the risk of test angle overshoot or process interruption

Safely test your ESD valves online with the FAITH partial stroke test device

To test your most critical ESD valves during operation, you partially stroke the valve. To avoid the process flow being interrupted during testing, the FAITH mechanically blocks the valve movement when it reaches the test angle. You are 100% guaranteed a safe test. The FAITH partial stroke is ATEX-certified and can therefore be used in any type of process environment, following the highest safety standards.

Safe testing of ESD valves

No-nonsense, reliable test

The FAITH partial stroke test device tells you if the valve will actually close upon request. You don’t need complicated software or additional wiring and you don’t have to interpret diagnostics. Test the entire system without bypassing components or additional equipment. Just put the system in test and initiate a shutdown. In the end, the valve moved, or it didn’t.

The ideal actuator maintenance tool

The FAITH partial stroke is perfectly suited to maintenance applications. When the actuator is in its blocked position, critical components can be replaced at any time without interrupting the process. Without the partial stroke testing system, control system components could only be replaced during plant downtime, when the actuator is in its fail position.

Testing without interrupting process flow

FAITH enables testing without interrupting process flow. Tests can be carried out more easily and more often, which ensures proper operation and reduces the deterioration of the valve. International standards such as IEC61508 and IEC61511 highly recommend testing of all ESD and HIPPS valves on a regular basis.

Partial stroke device for testing and maintenance of valves
FAITH partial stroke device for ESD testing

Suitable for SIL 3 applications

An FMEDA carried out by Exida shows that the PFD AVG value of the FAITH partial stroke comfortably falls within the range ≥ 10^-4 and < 10^-3. Therefore, it is perfectly suited to SIL3 applications.

No risk of overshoot

The FAITH partial stroke test device physically prevents the valve from moving past the specified test point, excluding the risk of actual shutdown due to trip or overshooting. For this reason, it is recognized by operators as a reliable test method for critical systems.

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Sofis offers you support through local service centers and a network of certified local service partners. This enables efficient execution of installation and maintenance of your Sofis products. We strive to create partnerships with our clients, providing a turnkey approach to service. This will result in a reduction of your total cost of ownership.

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