Well… temperature is easy. There are plenty of easy to use sensors available. It becomes a bit tricky for pH and ORP. Actually, you can’t just connect an ORP or pH sensor directly to an Arduino as you would with a temperature sensor. pH and ORP probes are generating very small voltage and current. Their output needs to be amplified quite a lot.<\/p>\n
As I am not an electronics specialist, I desperately looked for some “pre-build” pH and ORP sensor that would be quite easy to use. There are quite a few very nice and smart projects around :<\/p>\n
- \n
- LeoPhi<\/a>\u00a0: only pH though, no ORP<\/li>\n
- phDuino<\/a>\u00a0: still only pH<\/li>\n
- Arduiarium <\/a>: got pH, ORP, EC, \u00a01wire, I2C… a bit of an overkill for what I needed<\/li>\n
- and probably many more…<\/li>\n<\/ul>\n
I finally found Atlas Scientific pH <\/a>and ORP <\/a>stamps : not that expensive (before I had to pay VAT on parcel collection plus a fee… for VAT collection !), very nicely build, small, easy to use… Exactly what I needed.<\/p>\n
![\"orp&ph](\"http:\/\/interactingobjects.com\/wp-content\/uploads\/2013\/08\/orpph-640x480.png\")
<\/a><\/p>\nI then build a first prototype using an Arduino Ethernet. Not that I will be using ethernet capability but it has an SD card slot so that I could record collected data on a 2Gb SD. I would just have to connect the Arduino to a power source and plunge the 3 probes in the pool.<\/p>\n
![\"PoolDuino](\"http:\/\/interactingobjects.com\/wp-content\/uploads\/2013\/08\/PoolDuino-640x480.png\")
<\/a><\/p>\nI left the probe for around a day and a half running and took the SD card back, loaded the data into a Google Fusion table which gives the following results :<\/p>\n
[iframe width=”510″ height=”100″ scrolling=”no” frameborder=”no” src=”https:\/\/www.google.com\/fusiontables\/embedviz?containerId=gviz_canvas&q=select+col0%2C+col3+from+1zWy-wOUpEFkmKwPhjUALB4IOt2t_-BQKA_-HaLE+order+by+col0+asc&viz=GVIZ&t=AREA&rmax=250&uiversion=2&gco_forceIFrame=true&gco_hasLabelsColumn=true&width=510&height=100″]<\/p>\n
[iframe width=”510″ height=”100″ scrolling=”no” frameborder=”no” src=”https:\/\/www.google.com\/fusiontables\/embedviz?containerId=gviz_canvas&q=select+col0%2C+col1+from+1zWy-wOUpEFkmKwPhjUALB4IOt2t_-BQKA_-HaLE+order+by+col0+asc&viz=GVIZ&t=AREA&rmax=250&uiversion=2&gco_forceIFrame=true&gco_hasLabelsColumn=true&att=true&width=510&height=100″]<\/p>\n
[iframe width=”510″ height=”100″ scrolling=”no” frameborder=”no” src=”https:\/\/www.google.com\/fusiontables\/embedviz?containerId=gviz_canvas&q=select+col0%2C+col2+from+1zWy-wOUpEFkmKwPhjUALB4IOt2t_-BQKA_-HaLE+order+by+col0+asc&viz=GVIZ&t=AREA&rmax=250&uiversion=2&gco_forceIFrame=true&gco_hasLabelsColumn=true&width=510&height=100″]<\/p>\n
Works great ! The pH drop is due to adding (a bit too much) pH minus solution as pH was a bit high.<\/p>\n","protected":false},"excerpt":{"rendered":"
Because my parents have a quite expensive pool monitoring system that is not even able to grah collected data, I decided to have a look at what I can do. What do I need to measure ? pH ORP (redox) … Continue reading
- phDuino<\/a>\u00a0: still only pH<\/li>\n