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# Introducing Myself with my irrigation project

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(@will)
Prominent Member
Joined: 5 months ago
Posts: 817

Posted by: @huckohio

@wamagee

If you know the area and the sensor provided the pressure, you could calculate the height of the water (I think that's the equation Pressure=gravity * height).  It would require a pressure sensor at the bottom of the tube.

That's not the correct formula. Look at the dimensions

Pressure has units lbs/square inch (PSI)

Gravity has dimensions feet/second/second

and Height has units ft

So gravity x height has units feet x feet/second/second or square feet/second/second.

The relation is 1 foot of water is .433 PSI or 1 PSI = 2.31 ft of water

You can derive this by considering that 1 cubic foot of water weights about 62.4 pounds, so if we divide length and width by 12 to get inches, then a stack of water 1' high and 1" squared at the bottom weights 62.4/12/12 = .433 lbs/sq inch.

(@huckohio)
Estimable Member
Joined: 2 years ago
Posts: 183

LOL, wasn't taking a math test or trying to solve the problem...just making a casual suggestion.

(@wamagee)
Estimable Member
Joined: 3 months ago
Posts: 184
Topic starter
Posted by: @will FYI @byron

To test it, stand the 4" pipe you have on a piece of smooth waste board or shingle or plate and apply enough hot glue to prevent the joint from leaking.

Drop the sensor down to the bottom of the pipe.

Pour a quart of water into the top of the pipe; take a reading from the sensor; use a yardstick to "dip" the water in the pipe.

I am an optimist and so will put together part of my testing environment that I have been accumulating stuff for. In the next few days I will be receiving a piece of 1" clear PVC, for all the testing I will be doing a dipstick will not due.

This image will give you an idea of what I am intending to initially construct.  In the future all inputs and outputs of the tank will be simulated.

If it is determined that the Measuring Stack is no longer needed then in my testing environment the  Measuring Stack will represent the Tank. 🙂

Also in the final outdoors implementation the 1" clear PVC will be incorporated for simple visual determination of water level. Yes of course, it will need to be appropriately covered, with a removable cover, to keep light out and so keep algae out.

(@will)
Prominent Member
Joined: 5 months ago
Posts: 817

I understand that, but I wanted to point out that it isn't the right formula. I also wanted to show what is the right relationship and illustrate how it is derived to help with later calculations.

I'm not grading you and there will be no pop-quiz as you leave 🙂

huckOhio liked
(@wamagee)
Estimable Member
Joined: 3 months ago
Posts: 184
Topic starter
Posted by: @byron

Note the small metal cage used to keep the gauge upright, but off the bottom where bits of debris could effect the reading as show in the article.

I did not notice this so thanks for point out!

(@will)
Prominent Member
Joined: 5 months ago
Posts: 817

Posted by: @wamagee FYI @byron

I am an optimist and so will put together part of my testing environment that I have been accumulating stuff for. In the next few days I will be receiving a piece of 1" clear PVC, for all the testing I will be doing a dipstick will not due.

This image will give you an idea of what I am intending to initially construct.  In the future all inputs and outputs of the tank will be simulated.

That looks like the perfect testing setup !

(@wamagee)
Estimable Member
Joined: 3 months ago
Posts: 184
Topic starter
Posted by: @huckohio FYI @byron @will

My apologies if this is off track or has already been discussed (I haven't read this entire thread), but just looking at the above statement - could you use the calculation for a Water Column to determine the amount of water?  If you know the area and the sensor provided the pressure, you could calculate the height of the water (I think that's the equation Pressure=gravity * height).  It would require a pressure sensor at the bottom of the tube.

No apologies needed for not reading this entire thread, for sure I would not do especially since lots of time it is all over the place. Hopefully we get things to the point where the last few pages, or better single page, covers everything in great detail.

I believe somewhere in the back of my mind I remember seeing and planning to use the Water Column calculation you suggested. Thank You!

(@wamagee)
Estimable Member
Joined: 3 months ago
Posts: 184
Topic starter
Posted by: @huckohio

LOL, wasn't taking a math test or trying to solve the problem...just making a casual suggestion.

Gotta be careful with @will he will check you out! But I've learned that one: he does it without malice and two: I REALLY, REALLY, REALLY appreciate it.

huckOhio liked
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