Temperature - Hobo TidbiT temperature data logger
Parameter to be measured:
TidbiT v2 Water Temperature Data Logger - UTBI-001 
If there are several loggers in one location that require the exact same start time, a delayed start time can be set when the loggers are launched. This allows for easy comparison of the time series.
Batteries are not replaceable or rechargeable. Therefore each logger only has a 5 year life span regardless of deployment time.
What to watch out for:
The optic communication nodes on the logger need to be protected they will break with hard impacts. Deploying the loggers in small sections of PVC pipe provided enough protection for the loggers in a high energy stream environment. Several loggers can be attached to a capped thin PVC pipe and deployed at different depths below the streambed.
Loggers had a high failure rate. After deployment, some loggers only logged the temperature for a few days; the program in the logger may cause errors and not allow for communication or the battery may die rapidly. Partially depleted batteries found at purchase (In one case ~10% of loggers had 15% battery loss at time of purchase )
~$166 (US, 2013)
Projects that used the above equipment:
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