Flow meter updated parts list

You should be able to get something like this wherever you are:

http://www.amazon.co.uk/15mm-Water-Meter-Pulse-Output/dp/B0078NMBX6/ref=aag_m_pw_dp?ie=UTF8&m=A1JX55VWAQAMT3

cheaper than the Swissflow thingy and probably easier to deal with its output.

(I googled "hose pipe flow sensor")

You should be able to wire it directly to the Pi (no need for Arduino) and I'm sure no need for Carriots to buffer your data.

MK

Thanks Mike, but if I can elaborate slightly on what I need...

I'm wanting to create a kit for a school project so that they can build a flow meter from a basic raspberry pi circuit and attachments, hence being happy for a certain amount of expense and faff.

Any ideas?

Is it just the flow meter itself that is causing difficulty?

I had a project published in a US magazine that used a flow meter from (the enemy RS) which was quite cheap, however Futurlec (in Australia but charge in US$ and deliver from Asia) also have some inexpensive ones.

As you are in the UK, you might want to look at Rapidonline for the flow sensor. You might need to change the pulse counting count - if they all work by pulses per litre/gallon.

I always feel bad suggesting competitors on supplier forums.

Colin

If you have to buy a flow meter then Colin's suggestion of Rapid is a good one since they have a range of parts at much keener prices than the usual suppliers.

However, perhaps you want to make the flow sensor itself  - that would be interesting.

If it's for kids I would definately keep away from Carriots but use an Arduino or a Pi and wire the sensor (home made or bought) directly to the GPIO.

What's the budget for the sensor and what is the range of flows to be measured.

MK

Well, we're doing it for a reasonable size flow, like a sewer outflow, and wanting to use a Pi base to monitor the flows remotely. Budget is to fit, but it has to be a kit that can be handled by a set of teenagers. If that goes above and beyond, so be it.

Any ideas?

Wow - that's a different kind of flow sensor. What country are you based in - I'm sure that in the UK you would not be allowed to let schoolkids play with sewers.

The usual technology would be ultrasonic (can handle mixed liquids and solids) but this is a challenging system design issue (way beyond schoolkid level) so you would need to buy a sensor - and expect to pay £100s (many).

MK

Yes, a very different kind - but we wouldn't be letting our schoolkids into the sewer system, they would just be designing it, with help from professionals!

Thanks for the thoughts though, I'll take this back to my superiors and find out more about what exactly is going on.

If it isn't too late, I would suggest perhaps looking at measuring flow of a substance in either the school/college physics or chemistry lab.

Having said that, Rapid used to have school science flow kits. I'm not going to wander through all 9 pages, but here is the link to the flow page.

Rapid

Colin

Have you considered using peristaltic pumps at all?