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Topic: My Pressure & Flow Tester (Read 2298 times) previous topic - next topic

RobDrizzle

Completed Project. Total cost was somewhere around $350.00. It took about 9 months (partly because I bought and remodeled a house and had a kid..)

Basically, I'm a mechanical engineer who designs plumbing and fire protection system. My invention tests the building's domestic plumbing infrastructure on pre-war NYC co-op buildings and allows me and my company to determine if we can fulfill the owner's requirements for the plumbing before demolition happens. It also allows us to inform the owner if the plumbing system will need any booster pump systems, hot water heaters, etc., that are typically not in the budget, early on in the project before they have committed a cost of the renovation in their heads. Otherwise, if we do not alert them of any issues asap and wait to see what happens, my company will end up picking up the tab for redesigns and maybe even equipment costs. $$$ out of our pocket = unhappy boss.

I can also use this to help with booster system diagnosis and other random issues.

So basically the performance and specs are:
0-100 PSI
0-16 GPM
Medium Temp 50*-140*F
Accuracy +/- 4%
Pressure Drop Across device = negligible
Memory = 4 test results stored in non-volatile (can be as much as 80)
Data recall
Dimensions 13"L x 6"Dia
Weight = a hair over 5 lbs.

Uses two Seeedstudio flow sensors in parallel and a Barksdale pressure transducer. All three sensors are reporting back the a Arduino UNO. Display is a Sparkfun serial LCD and the pressure transducer amplifier is made from a TI INA-125. Has a battery monitoring circuit so I don't get caught with dead batteries. Feathers a filtered, fused power supply. Case is made from .125" thick clear plexiglass with .25" thick plexiglass end caps. I have had nothing but problems with every part of this project but learned a ton. Overall, not a bad little project, lol.

Next on the list is to change out the batteries for rechargeables and a charging circuit port to keep untrained hands out of my baby. I also want to expand on my battery monitor so it notifies the user of low batteries as well as dead batteries (relatively speaking)

I make it so that even the least experianced person could run the test after a quick explaination. If the GPM reads zero, the record button will only record the static (non-flowing) pressure. If the GPM is more than 0, than the record button will record the residual (flowing) pressure and at what GPM. You can go back and review saved tests, clear the memory or "logs" one by one or all at once. I have a extra secret diagnosis menu which will allow me to see raw data for calibration.

Let me know what you think or if you have any questions.
























liudr

Awesome project! Do you take it and measure pressure and flow rate at different places in a building a lot? This seems a very handy tool for that. Since you bought stuff from Seeed, you know they also have blue tooth bees, right? You could replace the display and buttons with blue tooth link to your phone :) Just run a Bluetooth terminal program and you can save all logs. Of course that will not be fool proof any more.

gravelbar

Very cool.  I've thought of pairing a couple of flow sensors like this (for our science models, see www.emriver.com); but how do you handle more than one interrupt with Arduino?

And seems those sensors would have a pretty good pressure drop; unless your flow rates are not that high; that's my problem with the impeller sensors.

And you're a good plumber; if I put the electronics and wet parts in one enclosure they would not last long!  :-)


robtillaart

Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

RobDrizzle

Sorry for the delays!!! Thanks guys!


Awesome project! Do you take it and measure pressure and flow rate at different places in a building a lot? This seems a very handy tool for that. Since you bought stuff from Seeed, you know they also have blue tooth bees, right? You could replace the display and buttons with blue tooth link to your phone :) Just run a Bluetooth terminal program and you can save all logs. Of course that will not be fool proof any more.


Yeah I work in about 30 buildings a year... So this thing will get plenty of use. I have only had it in the field twice but we haven't really opened any new projects lately... Go figure, something cool to play with and no where to use it.

At my company we use three different types of phones (droids, ipoops and blackberrys) so I'm not sure if blue tooth can be easily done over all of them.


Very cool.  I've thought of pairing a couple of flow sensors like this (for our science models, see www.emriver.com); but how do you handle more than one interrupt with Arduino?

And seems those sensors would have a pretty good pressure drop; unless your flow rates are not that high; that's my problem with the impeller sensors.

And you're a good plumber; if I put the electronics and wet parts in one enclosure they would not last long!  :-)


Because each sensor has just a signal pin going from low to high and the uno has two interrupt pins (D2 and D3) it was pretty easy... The code was pretty tricky and I had to get help with it. Pressure drop isn't all that bad (and a little bit is needed so that the pressure sensor can read something while it's flowing wide open)... The range is 0-16 gpm (8gpm per sensor) so running it at 10 gpm seems to be pretty friction free. I tested this for WEEKS! I had it hooked up in my downstairs shower with press on it the entire time. I had to fix two leaks and re-piped twice!


Well done !


Thanks!

RobDrizzle


Very cool.  I've thought of pairing a couple of flow sensors like this (for our science models, see www.emriver.com); but how do you handle more than one interrupt with Arduino?

And seems those sensors would have a pretty good pressure drop; unless your flow rates are not that high; that's my problem with the impeller sensors.

And you're a good plumber; if I put the electronics and wet parts in one enclosure they would not last long!  :-)




Here is the thread where someone was nice enough to beat interrupts into my head... Still don't quite understand it all but... It works

http://arduino.cc/forum/index.php/topic,73782.msg555012.html#msg555012

gravelbar

RobDrizzle; yeah, it's weird, but I learned from this thread there are two interrupt pins, but I still don't understand what happens when they overlap.

Also to OP, we do a lot of plastic fabrication in our lab.  Your enclosure is very cool.  If you have problems with cracking or wear, go with polycarbonate.  A little tricky to cut and glue (don't use high speed saws unless you know what you're doing, if it swarms in the saw, it can fly all over the place at high speed).  It's super tough; not quite as shiny and clear, but you'll never break it in normal use.  Also it really doesn't crack, so no worries with screws close to the edges, etc.  If you want scraps to play with Pmail me.

Steve

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