Responses from the mailing lists:
So excited to work on this at Barnraising! Someone correct me if I'm wrong, but the data loggers will collect and store the data (also potentially transmit!) from whatever sensor we figure to add to it. So if, like we're talking about here, we're interested in temperature, we'll add a sensor for that.
@cfastie posted back::
That is correct, the loggers can have many different kinds of sensors connected to them. Several sensors can be connected at the same time. Most loggers do not come with any sensors by default, although many have a real time clock with a thermometer which can be read and reported. The Nano Logger Kit comes with a sensor for barometric pressure and temperature. The sketch loaded on the Nano will start reading that sensor, saving the data to SD card, and displaying it on the serial monitor. If you connect another sensor, the sketch will have to be modified.
The Mini Pearl Logger Kit does not come with a sensor, but the starter sketch for it (available here) will read time and temperature data from the real time clock, save it to SD card, and display it on the serial monitor.
Although these loggers can send data via USB to a computer and display it (serial monitor), transmitting the data elsewhere requires additional hardware (e.g., a radio for wifi or cellular).
Carol's list of parameters that sensors should sense (Conductivity? Turbidity? pH, dissolved oxygen?) includes some of the top picks for water quality monitoring. Unfortunately, inexpensive, off-the-shelf sensors can't sense those things. One could use inexpensive components to make a conductivity sensor or turbidity sensor, but that is a rather big project. One can buy sensors for those parameters, but they cost maybe $100 to $400 and might not work with some Arduino based sensors.
The realm of DIY data logging is a small subset of the realm of environmental sensing.
Thanks, this is helpful. Coming from the environmental field in academia I have no idea what is available at low cost, and am looking forward to learning more and helping design studies for what is available.
So at the Barnraising, will we have different sensors to play with (and which ones)? Just temperature and time? I guess I'm still confused on how to help answer your original question, Stevie.
Thanks again for clarifications and follow ups. Carol for the question I posted, was looking for activities to "get acquainted" with the data loggers. Especially for people who have a water interest. For example: "What type of activity could we test out doing at the Barnraising in an hour or so with the data logger (or loggers) we're bringing?"
I'm interested in exploring what that activity might be in hopes we could test it out and write it up so others can do it as a "first step to working with your data logger."
I think we'll have a few data loggers at the Barnraising, including some of the ones Chris mentioned, and one or two sensors - definately temperature. These clarifications and follow up questions are really helpful!