Programming instructions

30 Designer’s Guide
Calsense
Alerts report, and at the central computer. This process continues each irrigation until the station is
repaired.
Similarly, if a remote control valve does not open, has an obstruction, or has a measured flow rate below
the Flow Meter minimum, the controller indicates a low flow on the display. If the backflow preventer or
water meter has been turned off, every station on the controller indicates this alert.
When used with a Flow Meter, the ET2000e monitors the system’s flow continuously and closes all of
the master valves in the system in the event of a mainline break. The thresholds for a mainline break are
user-configurable with unique values for irrigation, a master valve override, and all other times.
Restrictions
Certain hydraulic restrictions should be considered when designing an irrigation system with a Calsense
Flow Meter. Since the ET2000e Irrigation Controller independently acquires each station’s expected flow
rates, the Flow Meter must be installed in a pipe through which ALL AND ONLY
the water regulated by
the ET2000e Irrigation Controller flows. If a loop system exists or there are several irrigation controllers
fed off of one main line, the FLOWSENSE® option should be used to manage the system efficiently. See
Sharing Points of Connections
on page 23 for more information.
Permissible Pressure Loss
The permissible pressure loss is important due to pressure losses through the Flow Meter, the pipe
upstream of the Flow Meter, and the pipe downstream of the Flow Meter. The pipe must be the same
diameter as the Flow Meter to keep turbulence to a minimum. The length required up-stream of the
Flow Meter is ten times the Flow Meter size. For example, a 1.5-inch Flow Meter requires a minimum
upstream pipe length of 15 inches. The length required downstream of the Flow Meter is five times the
Flow Meter size. For example, a 1.5-inch Flow Meter requires a minimum downstream pipe length of 7.5
inches. The table below provides pressure losses for several Flow Meters with appropriate pipe
extensions.
Maximum Flow Meter Pressure
It is also important not to exceed the maximum recommended pressure rating of a Flow Meter. If
necessary, a pressure regulator should be placed upstream of the Flow Meter. The following table
provides the maximum recommended pressure rating for each Calsense Flow Meter:
10 gpm 20 gpm 30 gpm 40 gpm 50 gpm 60 gpm 70 gpm 80 gpm 90 gpm
FM-1B 0.60 2.20 5.00 8.80 -- -- -- -- --
FM-1.25B 0.20 0.60 1.20 2.10 3.30 4.80 6.50 8.50 10.00
80 gpm 100 gpm 140 gpm 180 gpm 240 gpm 280 gpm 320 gpm 360 gpm
FM-1.5 0.50 0.60 .80 -- -- -- -- --
FM-1.5B 0.50 0.60 .80 -- -- -- -- --
FM-2 0.10 0.20 0.40 0.70 1.20 -- -- --
FM-2B -- 0.50 0.90 1.60 2.60 -- -- --
FM-3 -- -- -- -- 0.10 0.20 0.20 0.30
Table 5: Pressure Loss in Pounds Per Square Inch (PSI) at Various Flow Rates