24 Jun
2016
24 Jun
'16
4:52 p.m.
On 06/22/16 21:44, James Knott via talk wrote:
On 06/22/2016 07:39 PM, Michael Galea via talk wrote:
If I really needed to know the answer to the question of "how much out", I would get ask the PLC to just count cycles and send me the count with a timestamp. That would tell.
And how accurate is the PLC? Typical CPU clock crystals aren't that accurate.
There are a few answers here. If you just run the device stand alone the data sheet (https://cdn.selinc.com//assets/Literature/Product%20Literature/Data%20Sheets...) promises "Unsynchronized Clock Drift Relay Powered: 2 minutes per year". If you use IEEE1588, 1uS. If you use NTP, well.. 1 mS? That's the figure I always plan on. -- Michael Galea