8 years ago
#12 Quote
The S-16, S-160, S-2-2, S-2-3 sensors have local on board FLASH storage for 64K readings.  Since each reading must be stored with the date and time it was taken the sensor, like all our sensors, maintains a real time clock with accurate date and time of day.  The sensor's clock is synchronized daily with the gateway's clock which is in turn  synchronized daily with the server's clock which is in turn synchronized daily with the US government's NIST standard time server.  In other words all reading time stamps are traceable back to a NIST time standard.

In order for logged readings to have a valid date the sensor must first have communicated with a gateway in order for its clock to be set to the current date and time.  If a sensor is logging and the battery is removed or it is powered off it will no longer have a valid date and subsequent readings will have an invalid date so its critical the battery not be removed while the sensor is logging to memory.  Note that all readings taken prior to the battery removal are unaffected as their date/time has been saved in FLASH and battery is not required for FLASH to maintain data integrity.  

It is best practice to verify a sensor is reading correctly on the web site and has a valid date and time prior to deploying the sensor in data logging mode.