[ISS Support Case] Null Values in Tags Post Power Outage

Last updated: October 17th, 2025

Description

After a power outage, random tags have null values. Never understood why but servers are on UPS, Switches are on UPS... everything should stay running through an outage and it does but after a blip random tags (reels, bool etc) across servers (abcip, gateway) show up as null. Can typically do a delta or full reimport of tags to resolve, but not today though. Has 7 workstations 6 intouch applications in Historian (IDAS) CORE v6.0 ABTCP v4.0 ABCIP v7.0 Gateway 6.0

Author: Kevin Modlin
Published: October 17th, 2025

Details:

Product: Historian

Version: 2017

Solution: [Solution is visible below when you're logged in and have a current subscription]

Date Created:	11/03/2022
Case:	82957

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