Tag properties can be filtered/blocked from being published by Transmission or Injectors.

They can also be filtered/ignored by Engine.

In either case, you can add the JSON/Scripting Name for the tag property to the Filtered Properties list in the appropriate module configuration.

MQTT Transmission and Injectors will publish any non-filtered tag properties which are different from the default Ignition tag property setting, including custom properties, in a BIRTH message.


For MQTT Transmission, the Filtered Properties list is available under Transmitters > Advanced settings

For AWS Injector, the Filtered Properties list is available under Tag Agents > Advanced settings

For Azure Injector, the Filtered Properties list is available under Tag Agents > Advanced settings

For Google Cloud Injector, the Filtered Properties list is available under Tag Agents > Advanced settings

For MQTT Engine, the Filtered Properties list is available under General > Advanced


The Filtered Properties list is a semicolon delimited list of Tag properties and by default contains: 

accessRights;clampMode;deadband;deadbandMode;formatString;historicalDeadband;historicalDeadbandMode;historicalDeadbandStyle;historyEnabled;historyMaxAge;historyMaxAgeUnits;historyProvider;historySampleRate;historySampleRateUnits;historyTagGroup;historyTimeDeadband;historyTimeDeadbandUnits;opcItemPath;opcServer;permissionModel;rawHigh;rawLow;sampleMode;scaleFactor;scaleMode;scaledHigh;scaledLow;tagGroup;valueSource;expression;expressionType;ConfiguredTagPath;eventScripts;readPermissions;writePermissions;eventScripts;parentEnabled;sourceTagPath


For example, to exclude the tag properties Engineering Units (engUnit), Engineering High Limit (engHigh) and Engineering Low Limit (engLow) from being published from Transmission you would extend the Filtered Properties as:

engUnit;engHigh;engLow;accessRights;clampMode;deadband;deadbandMode;formatString;historicalDeadband;historicalDeadbandMode;historicalDeadbandStyle;historyEnabled;historyMaxAge;historyMaxAgeUnits;historyProvider;historySampleRate;historySampleRateUnits;historyTagGroup;historyTimeDeadband;historyTimeDeadbandUnits;opcItemPath;opcServer;permissionModel;rawHigh;rawLow;sampleMode;scaleFactor;scaleMode;scaledHigh;scaledLow;tagGroup;valueSource;expression;expressionType;ConfiguredTagPath;eventScripts;readPermissions;writePermissions;eventScripts;parentEnabled;sourceTagPath


Known caveats:

If scaling is defined on an edge side tag and scaling properties are not filtered at Engine and Transmission, the scaling will be applied twice




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