[Clean Dude]

Sad I know, but i needed to find out, so thought I'd share my findings with y'all:

Back Pack Flow Rates: Litres Per Minute

Setting #1  -  1.03
Setting #2  -  1.37
Setting #3  -  1.83
Setting #4  -  1.94

(Myself and others have found setting #1 ample for all work, so you might want to
set yr standard pump to a similar setting?)

Also, I found the flow rate of my Clarke CPE100TF 1" Booster Pump & Pressure Tank
which i currently use as a transfer pump, to be 10.9 lpm.

Hope this is of some help to some of you!!

Thanks,

CD

[michael papworth]

Yes. This is my kind of information. This is what I'm on the forum for.

I'm interested in how you took the measurements.

I've done the same sort of thing in two different ways - and got the same results both times, but one much easier than the other.

[davids3511]

If a scales doesn't have a ml mode 1 gram of water = 1ml of water.

[[GQC] Tim]

I assume it would also very much depend on how high the pole goes, and the length of hose your using, or what diameter hose your using?

[davids3511]

I know for sure the backpack isn't. I fitted about 10 mtrs of pole hose and setting 2 became the equivelent of 1.5 and setting 3 became 2.5 (in my mind anyway).

[michael papworth]

Come on then Wally, how did you get your results?

OK.  Two points to apologise for in advance:

1 - I use a trolley system.

2 - I used to be a maths and physics teacher.

I set this as a problem for my 15-year-old son and me to solve together: How can I measure and then calculate the water flow rate on my trolley. He worked out the method with a bit of guidance. He then did the measurements and calculations.

1 - He placed a barrel onto my bathroom scales and noted the mass. m₁

2 - He then set the machine running at the setting I wanted to test for 10 minutes - just letting the water spray over the garden. (I have stop watches from my previous business.)

3 - He then noted the new mass of the barrel. m₂


As 1 litre of water has a mass of 1 kg, it was easy to calculate the flow rate from the change in mass divided by 10.

Flow rate = (m₁ - m₂)/10 (litres/minute)

We did it for 10 minutes to get one decimal place more accuracy. This was the main point of the exercise.

Accuracy of timing, +/- 1 second in 600 seconds = 0.16%
Accuracy of mass measurements +/- 0.1 kg in 25 kg = 0.4%

Total confidence in answer = +/- 0.6%

Had we only measured for 1 minute, the accuracy would have been +/- 2%

I really must get out more!

I also did pretty much the same as you, and got pretty much the same results - within the limits of experimental accuracy.

[[GQC] Tim]

LOL now that's extreme wally.   

Bucket, stop watch, 1 minute, get measuring cup, measure volume used.