Flow Switches

Flow Switches
Flow Switch Sensors with an electrical contact output at a specific flow rate have different types of switches, which are paddle, thermal, piezo, and shuttle/piston.

Questions

Question
What precautions should be taken when making an outdoor installation?
Answer
Keep the junction box above the nearest low point in the conduit run and make sure the conduit connection is sealed to prevent condensation from running into the switch.
Question
Why is the method of mounting a V4 of concern?
Answer
The vane and magnet keeper assembly near the hinge pin are very close to the mounting threads. Combined with the fact that pipe fittings are available in many variations, this produces a possibility that the customer will mount the switch in a fitting that prevents the vane from swinging. To make things worse, there is usually no way the customer can tell that this has happened. Mounting in a threaded branch connection avoids this clearance problem.
Question
How is "deadband" defined as related to the V4 switch?
Answer
Deadband is the difference between the switch actuation flow and switch deactuation flow; in general, V4 flow switches have a 45% deadband meaning deactuation occurs at approximately 55% of actuation flow.
Question
Can a V4 switch be installed in a vertical run of pipe?
Answer
Yes, but not the standard model. Vertical pipe installations must be specified on the order and require a special spring loaded vane. Only for use in vertical up-flow applications. Please see option -V in online configurator.
Question
What precautions should be taken when installing a V4 switch in an extremely high flow application?
Answer
Installation with a 2 1/2" threaded branch connection is recommended to allow the vane to swing out almost parallel to the flow to reduce stress on the vane and pressure drop in the system.