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Fertilizer Injection Unit

Discussion in 'Irrigation' started by JimLewis, Aug 10, 2004.

  1. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,298

    Matched PR means nothing here. DU is what you are looking for, and you will never get 100% DU in a sprinkler system .... EVER! Also, people that think that you can run fertilizer through your sprinkler system without having to perform maintenance to remove biological buildup are wrong.
     
  2. RandalatA1Sprinklers

    RandalatA1Sprinklers LawnSite Member
    Posts: 83

    What is DU? I would be willing to bet that he does not have MPR. Before I became a factory authorized installer I talked to dozens of contractors that have installed the EZ Flo. Once they switched to liquid they had no more problems.
     
  3. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,298

    DU = distribution uniformity, a term you should know if you are going to advise people on their irrigation systems. Also, there is no such animal as MPR. It is physically impossible to match PR in a given area with a sprinkler system.
     
  4. RandalatA1Sprinklers

    RandalatA1Sprinklers LawnSite Member
    Posts: 83

    well not to sound like an idiot but wouldnt du be the same thing as mpr? I know you cant get exact mpr but you can get it close enough to avoid stripes in the lawn. been in the business a lot of years and went to the rain bird acedemy and have never heard the term du
     
  5. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,298

    No offense Randal, but if you haven't heard of DU then you need to go back to the academy. Matched precipitation rate applies to sprinkler nozzle output (in this case) in a given area. It has essentially no meaning with respect to the entire area being irrigated. In other words, just because you have "matched" precipitation rate between your nozzles in no way means you have a uniform PR over the entire area ..... a.k.a. DU.
     
  6. RandalatA1Sprinklers

    RandalatA1Sprinklers LawnSite Member
    Posts: 83

    no offense taken. I fully understand what you are saying.
     
  7. RandalatA1Sprinklers

    RandalatA1Sprinklers LawnSite Member
    Posts: 83

    I just went back in my books frfom the rb acedemy. we just touched on du and i had a note in my book saying they teach more about it in an auditors course.

    DU= avg catch in the lowest quartile divided by the avg catch overall x 100

    derived from the Coefficient of Uniformity (CU) formula

    you are a pretty smart guy Kiril, where did you get all your knowledge? The auditors course is on my list of classes I want to take.

    its stuff like this that makes me laugh when a homeowner thinks we just go throw pipe and heads in the ground and call it a sprinkler system.
     
  8. Kiril

    Kiril LawnSite Fanatic
    Posts: 18,298

    DU doesn't necessarily have to be for the low quarter. It has been suggested the low half is a better value to use. These are the values I calculate for catch can audits with respect to DU and PR.

    UCC
    Cu
    DU25
    DU30
    DU50
    DU75
    UCCw_ave
    Cuw-ave
    DUw_ave25
    DUw_ave30
    DUw_ave50
    DUw_ave75
    PRave
    PR25
    PR30
    PR50
    PR75
    PRw_ave
    PRw_ave25
    PRw_ave30
    PRw_ave50
    PRw_ave75
     
  9. RandalatA1Sprinklers

    RandalatA1Sprinklers LawnSite Member
    Posts: 83

    I was just giving you the definition from the book. not trying to get in a pi$$ing match with you.
     
  10. 1idejim

    1idejim LawnSite Fanatic
    Posts: 8,819

    That's no pisn match, post more often.
    Posted via Mobile Device
     

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