The Greyline Instruments by Pulsar DFS 5.1 Doppler flow switch provides accurate flow control from outside of the pipe. Recommended for difficult liquids including wastewater, cooling water, slurries, sludge, chemicals, viscous liquids and abrasives, the DFS 5.1 is ideal for pump protection or to activate flow/no-flow alarms.
The DFS 5.1 ultrasonic sensor can be mounted on the outside of any metal or plastic pipes from 1/2 to 180″ I.D. and installs in minutes. The sensor continuously injects high frequency sound through the pipe wall and into the moving fluid where acoustic pulses are reflected back to the sensor from particles or bubbles in the fluid. The DFS 5.1 control relay can be set to turn ON and OFF at any flow rate between 0.25 and 10 ft/sec (0.075 to 3 m/sec). The DFS 5.1 relay time delay is adjustable from 0 to 80 seconds to prevent nuisance alarms and relay “chatter” in turbulent flow. Includes switch selectable “normal” and “failsafe” operating modes.
The DFS 5.1 has no moving parts and no maintenance is required. Installation can be made while the flow system is in full operation. No contact is made with the moving fluid and no holes are drilled in the pipe. There is no fouling or scale build-up on the sensor.
The compact, water tight electronics enclosure includes adjustable controls with separate ON and OFF relay set-points and time delay. A LED bargraph for flow rate and set points plus relay status are included. Switch adjustments and electrical connections are fast and easy.
