I need to build a device to read a temperature every 10 minutes, store it to a micro SD card with an accurate time stamp that is totally self contained and will operate for months without attention. It has to have low current consumption, so no displays or leds. It will not connect to WiFi or bluetooth since this unit will be miles from any network. It will primarily used to gather stream temperature data. Any suggestions on how to proceed? I am slightly beyond the blinking light project with Arduinos... Thanks!
I would use the Sparkfun OpenLog to store the data and a DS3231 RTC for the time.
If your power is perfectly stable for months at a time, fine, but it will not be a beginner project to run on batteries or deal with power outages.
You imply batteries but make no mention of the package you propose. You may need a small battery and so need to indulge in the black arts of sleep modes etc. You may be OK with a large deep-cycle battery, in which case it will all be easy. And then there may be matters of solar charging. Etc.,etc. So much to consider...
"Deep cycle" batteries are lead-acid. They don't work unattended for months at a time as they need regular
charging to prevent sulfation. Each battery chemisty has its own peculiarities you need to know about for
something like this - for instance not all batteries work in the cold, and each chemistry has a self-discharge
rate that depends on temperature.
If you allow a solar panel to top up a battery you can use much smaller battery and increase
the possible type of batteries you can use - but it gets more complex.
Thank you for the battery info however that is the part of the project in which I am quite experienced and have 600 Ahrs of gel cells with solar panels to keep power to the unit.... I am really at a loss on how to proceed to get the RTC, arduino, a temperature sensor, and the Sparkfun OpenLog working together to take and store readings every 10 minutes. I will be reading the SD cards on a laptop off site. Everything I am finding seems to be more interested in flashing lights, lcd displays and turning on the coffeepot....Lol. I just need a temperature logger that will record for months unattended.
NVJims:
I am really at a loss on how to proceed to get the RTC, arduino, a temperature sensor, and the Sparkfun OpenLog working together to take and store readings every 10 minutes.
So start at the beginning;
Check you can read the temperature sensor and print results to the serial monitor.
Check you can read the RTC and print out the time.
Use the alarm feature of the RTC to turn on an LED
Check you can put your Arduino to sleep (and check the current of cource) and wake it up with a switch.
You have decent power, and thus may not need to get fancy in that department, but you probably ought to use a decent regulator, rather than use those that usually come with Arduino.
Temperature
One consideration is how close you can actually get to the river.
Clock
https://bildr.org/2011/03/ds1307-arduino/
works with DS3231 without modification
You may prefer to dump the data via bluetooth, rather than winkle out the SD card.
You can buy these things for relatively low cost , have a google .
hammy:
You can buy these things for relatively low cost , have a google .
Yep, HOBO pendant or tidbit loggers are really user-friendly and with 10 minute readings will last for as long as you need. Accuracy isn't great isn't great (-/+ 0.5C), but it depends on what you need.