When the gateway restarts, the historian treats the first value it receives from the OPC server or tag as a new "initial value" and stores it, even if the value is identical to the last recorded one which cause duplicates values in historian. I want to know how cab prevent this behaviour?
A gateway restart means there's a gap in Ignition's knowledge of what might have gone on while it wasn't paying attention. Recording the new starting value, even if duplicate, ensures accurate history from the starting timestamp forward.
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