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Water Quality Sensor

Developed during the Water Hackathon on March 23-25 in New York City, the water quality sensor is a multipurpose tool for collecting data remotely. This tool is rapidly changing and is being used as part of the on going research initiative called []( (archived). This tool consists of an Arduino microcontroller, a set of water quality sensors, and a network connection module. As currently developed this tool uses a GSM based cellular module to send data via SMS. For this design a custom arduino shield was created. This shield allows the arduino to be powered by a 3.7v lithium ion battery. The shield includes a 3.3v to 5v setup circuit based on the Adafruit Mintyboost. Currently there are two versions of the shield. Both versions use the waterproof digital temperature sensor from Adafruit. The shields differ in the electrical conductivity probe they are designed to use. Electrical conductivity (EC) is basically a measure of water's purity. The more pure the water the less conductive. When pollutants enter water it usually causes an increase in EC. Lots of details about EC are available from the EPA site. The first probe is DIY. It was created using designs published in the book Environmental Monitoring with Arduino. This probe uses readily available parts from most Radio Shack stores. More details about this probe will hopefully be posted with permission from the book's author. The second type of electrical conductivity sensor is much more expensive but is lab quality. Its available from Atlas Scientific. Here is the shield designed for the Atlas Scientific probe. Connected between the battery and the Arduino is a solar charging circuit. And also use for [quality control systems]( This is connected to a 2w 6v solar panel. Both of these are available from Adafruit. The data from this sensor is uploaded to Pachube using a GPRS shield from Seeedstudio. The initial prototype was using a TCP/IP connection, which requires a SIM card with a data plan, but the Arduino code is poorly optimized for long durations. The second prototype is sending SMS messages directly to Pachube's beta SMS gateway. Here is the sensor all wired up in a pelican case with the solar panel on the top. ...

Author Comment Last activity Moderation
EdMallon "Progress with the LED light sensor technique revealed that you can can also measure temperature by timing the reverse-bias charge decay on ANY type..." | Read more » over 2 years ago
EdMallon "With the school year beginning we have some new instructors spinning up their own courses around the classroom logger released earlier this year. ..." | Read more » almost 3 years ago
dominictoretto1831997 "I wrong or this could be considered as "method"? Its own particularities made the KnowFlow a different one than Coqui, Riffle or Mae d'aigua. I'm b..." | Read more » almost 3 years ago
roberts_ecofarm " Really liked the tutorials! " | Read more » about 3 years ago
EdMallon " I've been experimenting with the Input Capture Unit on our pro mini's 329p processor, and with it you can make ‘High-Resolution’ Sensor Readings ..." | Read more » about 3 years ago
EdMallon "You can use a Pro Mini (or any other Arduino with an Atmel processor) to measure temperature using only the mcu. I think this is the best "No-Par..." | Read more » over 3 years ago
EdMallon "A high-school teacher friend asked us for faster build that is less dependent on soldering because they don't have the budget for that kit. So we'v..." | Read more » over 3 years ago
EdMallon "Dr. Beddow's instrumentation students have been building our EDU logger for more than three years and, based on that experience, we've redesigned t..." | Read more » over 3 years ago
DoraWest "Pleasant post. I was checking continually this online journal and I am awed! To a great degree supportive data extraordinarily the last part I admi..." | Read more » over 3 years ago
warren " Hi, Ed; thanks for reporting this; we'll take a look ASAP. I've opened an issue for you here if you'd like to provide any other information (for e..." | Read more » over 3 years ago
EdMallon "For some months now I've been unable to upload images to comment posts in this research note. I've tried multiple different browsers. Though the im..." | Read more » over 3 years ago
roberts_ecofarm " @EdMallon Glad to see more video links. The basic logger build videos you did were great. Really helped me. Thanks for continuing to share. " | Read more » over 3 years ago
EdMallon "I finally completed the set of logger build tutorials on Youtube, to go with the screw terminal logger posted in 2017: Pro Mini Logger Build: Bat..." | Read more » over 3 years ago
EdMallon "Posted a new Tutorial: Adding the SSD1306 OLED Screen to an Arduino Logger (without a library) This is the third in our series about using shift-o..." | Read more » over 3 years ago
EdMallon "That's very tempting, but I'm not sure I can add another thing to the plate this year. I still have several important new features to add to the co..." | Read more » almost 4 years ago
Bronwen "Hi @EdMallon -- this is so great! I was just scrolling through all of the updates on here, and was wondering if you had any interest in turning thi..." | Read more » almost 4 years ago
MadTinker "Just a quick update on the status of this project. Willow Creek is going through a couple of serious events. First, the stretch of the stream where..." | Read more » almost 4 years ago
EdMallon "This is a follow-up to our post about using Nokia 5110 screens on three unused analog lines with shift-out​. That saved me from messing with the h..." | Read more » almost 4 years ago
EdMallon "While the logger core is generic, surface deployments tend to use the 4" housing (which is easy to build) while the underwater deployments (~ half ..." | Read more » almost 4 years ago
hpprinter1995 "Nice And Informative Website. Please Keep Continue Such Kind Of Effort. Contact Us And Get On-Site HP Printer Support & HP Scanner Support. Our..." | Read more » almost 4 years ago
pdhixenbaugh "I'm also looking to measure Conductivity, and I have a Riffle. So you have any advice for what sensor to buy, with the memory constraints and other..." | Read more » about 4 years ago
shanlter "Hi @mrkhan1994 Thanks for your interest, I haven't tried, but I know @rockets have used this iot module to get data wirelessly (it need wifi tho). ..." | Read more » about 4 years ago
mrkhan1994 "great project, can you guy help me monitor the signal wirelessly " | Read more » about 4 years ago
EdMallon "A visiting researcher dropped by our humble basement workshop with questions about the physical skill level students would need if they added one o..." | Read more » about 4 years ago