Can somebody explain how to use Catch Cup data with iro


I understand placing catch cups and recording measurements. I even get how to interpret the calculations produced by the Orbit watering schedule site.

However, entering that data into the iro is confusing.

The only thing I came up with is to create a custom nozzle with the observed flow rate (GPM) and putting in the zone size.

Any better suggestions?

Follow that formula and make a custom head with that pr.

@RVRoadie. Assuming that you used the Orbit cups and their calculator, you can use the precipitation rate from their calculator and then, yes, plug it into a custom nozzle. Just make sure that you enter the value for in/hr. You mentioned GPM in your posting so I wanted to be sure.

You are right. I get the PR(in/hr) from the Orbit calculator, and also the Distribution Uniformity. I create a custom nozzle with the PR rate, and use the Distribution Uniformity to set the Efficiency %. I fix up the area to match the size of the station, and leave everything else alone.

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@RVRoadie That sounds about right! What were highs & lows of your catch cup data, and the total PR & efficiency ? Just curious.

Cup Volumes: 50, 22, 18, 25, 32, 25, 24, 15, 18, 15, 16. This was for 10 minutes. I probably should have done 20.

Distribution Uniformity 63%
PR 0.53 in/hr


@RVRoadie. That looks similar to mine. Thanks for sharing the info.

@azdavidr @RVRoadie Late to the party, I don’t know if you saw this calculator.

Really easy to determine PR in/hr.


Thanks @franz. FYI a couple of us determined a while back that the hydrorain and orbit calculators are identical. Catch Cups. @RVRoadie ended up getting to it from the Orbit side.

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