Looking to see if there exists a solenoid valve with a third wire that senses the valve is closed when power is off. Does this exist?

The need is to signal another control outside of the subsystem to shut down if the inner system solenoid fails. The idea is that the always on status has caused some level of corrosion or other effect on the actuator so it will not close properly.

 

The feature/action that you are looking for is called 'proof-of-closure'.

You can Google for vendors and models.

This link goes to a solenoid valve with a proof-of-closure switch:

https://www.ascovalve.com/Common/PDFFiles/Product/8043R3.pdf

 

So the term 'position feedback' is only applicable to linear control valves?

> The feature/action that you are looking for is called 'proof-of-closure'.

 

Just to be clear, are you looking for valve position or loop/solenoid failure? If you are looking to monitor the loop to include the solenoid coil (i.e., Cold Coil Monitoring) take a look at Pretech Solutions Inc. at www.pretechsolutioninc.com or contact me offline at [email protected]

 

> The need is to signal another control outside of the subsystem to
> shut down if the inner system solenoid fails.
> The idea is that the always on status has caused some level of corrosion
> or other effect on the actuator so it will not close properly.

At first I thought if that's a DC solenoid it would be easy to sense the lack of field with a reed switch. But on reading further you talk about corrosion sticking it open, so what you are really looking for is zero flow.

Flow switches rarely work especially in a situation where it's normally flowing.

What you need is a flow transmitter.
A thermal mass flowmeter perhaps
Or
DP cell with integral orifice plate.