Sensor Orientation
For the best results, 500 Series sensors should be mounted with the faceplate in the vertical plane.
Mounting the device with the flow connections uppermost can help eliminate entrained air from your
system.
Flow Direction
The 500 Series Metering Flow Switch is not sensitive to flow direction. Flow can be introduced to the
sensor from either side.
NPT pipe thread connections
Pipe threads seal by making metal-to-metal contact between male and female components.
Consequently they are particularly prone to the damaging effects of galling, which occurs when two
surfaces move against each other under pressure. When installing pipe threads it is essential to use a
high quality lubricating and sealing material.
•
Use Teflon tape or a PTFE-based liquid sealant to provide lubrication for the junction and a leak-tight
connection at both input and output connections. Real-Tuff and Hercules are two of many suitable
brands of PTFE-based sealants.
•
Do not over-tighten the connection. Refer to instructions for installation of the mating fittings for
information on torque requirements.
•
Leak testing of all connections in your flow circuit is recommended. Pressurizing the system with air
and external testing with a dilute soap solution can help identify leaking connections.
SAE straight thread connections
With these connectors, an O-ring makes the seal while the threads hold the connecting assembly in
place. Straight thread connections should receive a small amount of high-pressure lubricant before
installation to prevent galling.
Non-adjustable fittings
1. Bring the non-adjustable fitting into firm
contact with the face of the port, using a
wrench.
2. Check to be certain that the O-ring fits
easily into the non-threaded receiving
area of the port, and is not pinched.
500TRM-002
Page 10 of 22
March 2007
