2 years ago
#162 Quote
For data logging sensors to have an accurate reading timestamp they need to have an accurate "Real Time Clock" or RTC.  All of our sensors and gateways use a battery backed real time clock and all date and times are synchronized end to end through our system to a NIST time server.  But do beware that if a battery backed clock loses power (ie you remove the battery from a sensor) that when power is restored the sensor will not have a correct date and time UNTIL it has communicated with a gateway.  After it has communicated with a gateway it will once again have a correct date and time.  Note the same is true of a gateway as well.  Gateways are shipped with time and date set correctly and come with a CR2032 coin cell that has a 5-7 year life.  So if/when you replace the gateway's battery it must be connected to the internet and online with our server to sync its clock.

It is CRITICAL that if you plan to use our data logging sensors in data logging mode, ie without a gateway nearby, that those sensors have the correct date and time set and after that is done the battery CAN NOT BE REMOVED.