1-wire pressure senors???

Frederick

Greetings,



I am contemplating adding a datanab Barionet to monitor, and eventually control, my steam heating system, 12 flat pearless boiler.  There are a plethora of  1-wire temperature sensors, but I have yet to find a 1-wire pressure sensor suitable for monitoring steam pressure, i.e. along side the Presturtrols.  Plenty of atmospheric pressure sensors though.  Anyone do this?  Recommendations?



Thanks in advance,



Fred



<a href="http://www.datanab.com/docs/barix/barionet/manuals/BarioNet/Barionet_Manual.pdf">http://www.datanab.com/docs/barix/barionet/manuals/BarioNet/Barionet_Manual.pdf</a>

Magnehelic

Nope.....not gonna happen.

Fred......we do DDC controls all the time.  You need a 0-5VDC sensor, which is not very available, or you will need to buy a 4-20ma output pressure transmitter and install a high accuracy 250 ohm resitor in parallel with the transmitter (that will convert it from a 4-20ma to a ONE TO FIVE VOLT DC SIGNAL(1-5vdc signal).

Jamie Hall

ah ha...

after reading part of the manual... it's not one wire.  It's one cable -- with at least two wires inside it.  That's clearer.



Depending on the steam pressure you are sensing, you may be able to use an atmospheric pressure sensor, provided the range is wide enough.  Check the range of the device, and do your conversions and see.

Frederick

"1-wire"/iButton and the connection . . .

"1-wire"  is the name.  It is only one wire, but it can have one, two or three wires.  All the control/data is on one wire, even for a whole network of devices connected together.  You can connect the ground to a common ground, i.e.  the pipe, but I would suspect that would not work to well so you would run a ground wire in the same cable. Some 1-wire devices use parasitic power, i.e. charge a capacitor while not communicating, other 1-wire devices use a separate power wire.  Nifty and simple and at least for temperature sensors reasonably priced.



None of the pressure sensors seem to have iron pipe threading and thus difficult to hookup to steam boiler system.  I saw one web page where a tire pressure gauge was jerry rigged with a 1-wire interface, but alas the range was 5+psi and I am interested in 1-5psi.



Fred

The Steam Whisperer (Formerly Boilerpro)

I've used...

are Cecomp from Libertyville, IL? for mearuring pressure in ounces

Magnehelic

Try This Out

http://workaci.com/content/agp

Then click on "distributors" at the top and see where you can get it.  The LIST price shows as $285.00 but I buy them from alpscontrols for under 80 bucks.  Like I said, you are going to need to get a 4-20ma output transmitter and wire it in parallel with a 250 ohm resistor (1% or less tolerance) to change the signal to a 1-5vdc for your controller.