4

First time poster here so let me know if I'm missing key info.

I'm helping a friend create an Arduino-powered data collection system for his coffee roaster, and we'd like to track the natural gas pressure (in W.C.) being sent to the burners.

Can anyone recommend a low-cost solution for this? I think we'd have to have a plumber install it, because it should be inserted into the pipe leading to the already-installed analog readout and allow us to push data to a microcontroller. I don't know the exact diameter of the copper pipe but I think it's a standard size. Even if someone could point me in the direction of the right class of device and/or a manufacturer, that would be great.

Thanks.

EDIT: The range we need is 0-16" W.C. or 0-40 mbar

Todd Price
  • 141
  • 5
  • If "low cost" means something you build yourself I would stay away from that for obvious reasons. Just be safe try to find a real pressure transducer which is designed for that application. If you just want to compare the current pressure to a reference value an optical sensor over the analog gauge might work. But think about what happens if this setup fails. – 0x6d64 Jun 15 '12 at 16:06
  • I'm hadn't intended to build it myself, but that was before your suggestion of an optical sensor over the analog gauge. I don't however want to obscure the readout of the analog gauge with this solution, so I'm not sure that would be an optimal solution. Interesting idea that I might still try out though. – Todd Price Jun 15 '12 at 16:15

1 Answers1

1

I'm no expert on the plumbing/safety aspects, but I think you are probably looking for something like this sensor from Honeywell

Pressure sensor

The above came from Farnell, where there are 677 other options to look at.
Many of the expensive ones are incorporated into some metal piping which I imagine can be inserted in between or on a tap off (depending on design), and some of the cheapest are nothing more than an IC with a small tube attached, but I'm not sure how you could use these safely.

I would ask your plumber about suitability before purchasing anything, you can download a copy of the datasheet for measurements/specs.
Digikey/Mouser/RS/etc are likely to have other options also.

Oli Glaser
  • 54,990
  • 3
  • 76
  • 147
  • This is on the right track Oli, thanks for the lead. The form factor is exactly what I was picturing. I think I need something that measures lower pressures though, since 1 PSI = 27.6 WCI (Water Column inches), and my range is 0-16 WCI. – Todd Price Jun 16 '12 at 16:35
  • Yes, most of the ones in that form factor seem to be quite high pressure ranges. There is [this one](http://uk.farnell.com/keller/pr21sr-80444-3-1/pressure-transducer-0-1bar-g/dp/7099460) that does 0-1 bar. You may have to look at using one of the little plastic IC type ones like [this](http://uk.farnell.com/honeywell-s-c/xpx01d/sensor-pressure-1-to-1psi/dp/1971753) - possibly fitted inside the end of a pipe. – Oli Glaser Jun 16 '12 at 18:14