Calsense Flow Meters, model FM, are used with all Calsense irrigation controllers to monitor real-time flow of potable or non-potable water making them important tools in detecting mainline and lateral breaks on an irrigation system. Real-time system flows are learned automatically at night when irrigation comes on so that constant flow rates are measured, in order to provide the most accurate and reliable monitoring of breaks and problems as they occur. 

Flow Meter Details

The Calsense Flow Meter features a proprietary, non-magnetic sensing mechanism and a six-bladed design. Its unique, forward-swept impeller design provides higher, more constant torque than less efficient four-blade designs, and is less prone to fouling by water-borne debris. The advanced design of the Calsense Flow Meter coupled with an absence of magnetic drag delivers improved operation and consistent repeatability at lower flow rates.

As liquid flow turns the Flow Meter impeller blades, a low impedance 9VDC signal is transmitted with a frequency proportional to the flow rate. The signal can travel up to 2,000’ between the Flow Meter and the Calsense field controller without the need of amplification. Controllers require no additional interface and supply the DC signal directly to the Flow Meter.

Flow Meter Specifications

FM-1B, FM-1.25B, FM-1.5B Parameters

Accuracy: +/- 1% of full scale

Linearity: +/- 0.7%

Repeatability: +/- 0.7%

Flow Range: 0.5 to 15 feet/second

Max. Pressure: 400 psi@150°F (65.5°C)

FM-2B Parameters

Accuracy: +/- 1% of full scale

Linearity: +/- 1% Repeatability: +/- 1%

Flow Range: 1 to 30 feet/second

Max. Pressure: 200 psi@150°F (65.5°C)

FM-1.5, FM-2, FM-3 Parameters:

Accuracy: +/- 1% of full scale

Linearity: +/- 0.5%

Repeatability: +/- 0.5%

Flow Range: 1 to 30 feet/second

Max. Pressure: 100 psi@68°F (20°C)

(See Calsense Designers Guide for more details)