Can someone please recommend a pH and/or TDS sensor that is fairly easy to conn
Brann Fenix
Posts: 57
Hi again!
I have been searching around the forum without much luck at finding examples or info other than a thread or two on the TDS/pH subject... Please forgive my lack understanding on some of these subjects since I am still learning the ropes myself. I already own a pH meter and a TDS meter which are both pen meters and lack remote probes, or I would have been testing with them long ago. I still think the meters will be a great help calibrating anything I can cook up with the help of anyone on the forum with an idea. Now, here is my dream... which I'm sure should come crashing down at one point or another but here goes:
I am looking for something along these lines:
1. Something cost effective*read cheap*... I know I have to replace the electrode in my pen meter every year or so and I can only figure that one that is in water 24/7 would need to be replaced sooner rather than later.
2. It can't require a massive amount of code or I/O pins to read from since my code is already getting kinda fat and running low on VAR space.
3. It would be amazing if someone had sample codes or experience with a probe they can recommend, but at this point I think I will be happy with a point in the right direction.
4. Some type of simple output like a low votage or something that could be monitored with the BS2... I guess that kinda connects with the not needing tons of code dream heh [noparse]:)[/noparse]
5. A pH probe is more important to me at this second, but I will gladly take info on anything anyone can think of.
I have read the "Looking for a homebrew salinity test circuit... " thread here http://forums.parallax.com/forums/default.aspx?f=5&m=131159 and I have also been reading over what the Applied Sensor workbook had to offer. The Applied sensors book did not really address pH and the salinity testing stuff while very interesting seemed to have a lot of things that could go wrong and screw up the readings like water temp, depth, ect.
I saw someone recommend the the site http://www.eutechinst.com/ and while they do sell probes and such it is a little over my head at the moment.
Thanks in advance,
Brann
I have been searching around the forum without much luck at finding examples or info other than a thread or two on the TDS/pH subject... Please forgive my lack understanding on some of these subjects since I am still learning the ropes myself. I already own a pH meter and a TDS meter which are both pen meters and lack remote probes, or I would have been testing with them long ago. I still think the meters will be a great help calibrating anything I can cook up with the help of anyone on the forum with an idea. Now, here is my dream... which I'm sure should come crashing down at one point or another but here goes:
I am looking for something along these lines:
1. Something cost effective*read cheap*... I know I have to replace the electrode in my pen meter every year or so and I can only figure that one that is in water 24/7 would need to be replaced sooner rather than later.
2. It can't require a massive amount of code or I/O pins to read from since my code is already getting kinda fat and running low on VAR space.
3. It would be amazing if someone had sample codes or experience with a probe they can recommend, but at this point I think I will be happy with a point in the right direction.
4. Some type of simple output like a low votage or something that could be monitored with the BS2... I guess that kinda connects with the not needing tons of code dream heh [noparse]:)[/noparse]
5. A pH probe is more important to me at this second, but I will gladly take info on anything anyone can think of.
I have read the "Looking for a homebrew salinity test circuit... " thread here http://forums.parallax.com/forums/default.aspx?f=5&m=131159 and I have also been reading over what the Applied Sensor workbook had to offer. The Applied sensors book did not really address pH and the salinity testing stuff while very interesting seemed to have a lot of things that could go wrong and screw up the readings like water temp, depth, ect.
I saw someone recommend the the site http://www.eutechinst.com/ and while they do sell probes and such it is a little over my head at the moment.
Thanks in advance,
Brann
Comments
www.vernier.com/probes/index.html
The PH-BTA has a built in amplifier with an offset, so you can connect it directly to an ADC. Software would be easy, because the voltage is linear 0.25 volts per pH unit,
pH = (volts - 1.75) * 4
The harder part is the calibration and standardization and temperature compensation.
For long term deployments, I'd recommend Sensorex probes...
www.sensorex.com/
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Tracy Allen
www.emesystems.com