How do I calculate pressure and flow for my irrigation system?

To ensure that the irrigation system works properly later on, we always determine the available water volume at 3.5 bar. Although we plan the sprinklers for 2.8 bar at the sprinkler, 0.2–0.5 bar is usually lost along the way (valve box, pipes, distance). That is why we measure higher at the start. The best way to determine the amount of water is to use our measuring device.

Here's how to do it:

1. Connect the measuring device to the tap.
2. Turn the tap on fully. 
3. Reduce the flow rate on the measuring device until the pressure gauge reads 3.5 bar.
4. Fill a 10-litre bucket with water and time how long it takes in seconds.
5. Calculate using this formula:
   (10 l × 3.6) / time in seconds = water volume in m³/h

This value determines how many sprinklers we can run simultaneously later on.

In short: We plan for 2.8 bar at the sprinkler, but measure at 3.5 bar because pressure is lost along the way.