# adjusting precip rate via meter



## vnephologist (Aug 4, 2017)

After some irrigation issues this past year and after reading some tips here, I decided to do some 10 minute runs in each zone and fine tune my precip rate based on the results. I was hoping to get another set of eyes on my math...

((((end cubic ft - start cubic ft)*7.48052)/10)/sqft)/0.0104 = in/hr

My meter was in cubic feet, so I first converted to gallons (*7.48052), then divided by 10 (min) to get GPM. I then divided by sqft in the zone to get GPM per sq foot. I then found a conversion on the web for in/hr (0.0104). The values are in the ballpark for my MP Rotators, but definitely needed some adjustment. I also took the opportunity to more closely measure my square footage and was surprised to find that its only 2156 instead of the 2500 I've been using for all of my chemical calcs!


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## g-man (Jun 15, 2017)

I prefer to place measuring cups or tuna cans and run an one hour cycle on all the overlapping zones. I find it more accurate than the 10min run meter approach.

Last time I did a check I just placed them in the night and checked them in the am after a normal cycle.


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## Pete1313 (May 3, 2017)

Double checked.. The math is correct. :thumbsup:

I used the meter test you did as a baseline for my irrigation. I then audited it by measuring with These. The meter test will get you close per zone, but actual will always be alittle less since some irrigation will be lost in the air/wind. I used the gauges to check for balance issues between heads in a zone, as well as check for coverage. I have PGP rotors so when I found a spot within a zone that had a lower precip rate then desired, I just popped in the next size up nozzle.


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## Ware (Jan 28, 2017)

I agree with these guys. The meter will tell you how much water you're sending to the zone, but the gauges will tell you if there are any problem areas within the zone. Both are good to know. :thumbup:


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