The solenoid valve operates in the open state when there is a fault; it is now forced to be closed. What is its state after the instrument air supply is cut off – open or closed?
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The solenoid valve has a fault-open mode with a reset button; it is now forced to be closed. Will it be in the open or closed state after the instrument air supply is cut off?
Broken instrument air = fault, so it should be “on”; is that correct?
In the fault-open condition, the spring of the actuator takes over, and when there is no force applied, the valve remains in the open state. As the original poster said, the valve will open
The original poster didn’t make it clear: 1. Is it a solenoid valve? Is it still the solenoid valve controlling the pneumatic actuator? 2. For solenoid valves, a fault refers to a loss of power rather than a lack of air supply; forcing it to open means supplying power to the solenoid valve, so it remains open even when there is no air supply. 3. If a solenoid valve is used to control a pneumatic actuator, it is also necessary to determine whether the pneumatic actuator operates in fail-open or fail-close mode A fault in a pneumatic actuator refers to a lack of air supply; in the case of a faulty open condition, the pneumatic actuator opens, but the solenoid valve still forces it to stay open
It wasn’t asked how to proceed with forcing the instrument specifically.