Internet time vs RTC

General
1

Hi, I'm wondering what would be best for time-based events, RTC (and how to interface it) VS. Internet time.

I'm running Node-RED on a Raspberry Pi 3 b+.

Thanks!

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An RTC is pretty much a waste of money on a general-purpose compute device that is always connected to the Internet.

So you would only want to get an RTC if your device spent a lot of time (12hrs or more maybe?) offline. The default installation for something like Rasbian is more than sufficient to keep a Pi within a few seconds at worse (I've not actually checked to be honest but large offsets impact things like cryptography so tend to be noticable) maybe only a few ms? I think that the default checks the NTP service every hour? I'd expect the internal clock to be within a few seconds over 24hrs, maybe better.

3

Thanks! That helps a lot.

I was on the fence between keeping my pi connected to a network or setup my pi as a standalone with an RTC keeping the time. It sounds way simpler to just leave it on the network.

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