The "normalLowerLimit" property specifies the low range of a normal collected value. An outlier is below this range. A change is saveable when it is greater than or equal to the normal upper limit.
The following chart shows a connector not saving a tag's value because it is outside the normal range.

Scenario
A connector may collect a value from a water pressure sensor once every 100 milliseconds. The device's pressure is turbulent and has outliers. A normal pressure is between 30 and 50. To not persist outliers, set "normalLowerLimit" to 30 and "normalUpperLimit" to 50.

Code example

{
 "api": "hub",
 "action": "createInput",
 "params": {
   "inputName": "modbusTCP",
   "serviceName": "modbus",
   "tableName": "modbusTableTCP",
   
   "dataCollectionIntervalMilliseconds": 100,      
   "dataPersistenceStrategy": "onChange",

   "maxUnsavedEvents": 360,
  
   "settings": {      
     "modbusProtocol": "TCP",
     "modbusServer": "127.0.0.1",
     "modbusServerPort": 502,
     
     "propertyMapList": [
       {
         "propertyPath": "waterPressure",
         "modbusDataAccess": "holdingregister",
         "modbusDataAddress": 4003,
         "modbusDataType": "int16Signed",

         "normalLowerLimit": 30,
         "normalUpperLimit": 50
       }
     ]
     
   }
 },
 "authToken": "replaceWithAuthTokenFromCreateSession"
}

Notes

• The connector uses this property only when the "dataPersistenceStrategy" is "onChange". 
• The following properties work together to save meaningful data changes.
  • "dataPersistenceStrategy"
  • "maxUnsavedEvents"
  • "normalLowerLimit"
  • "normalUpperLimit"
  • "deadbandLowerLimit"
  • "deadbandUpperLimit"
  • "significantMagnitude" 
  • "onChangeScope"
  • "onChangeScopeTags"
  • "onChangeTrigger"
  • "onChangeTriggerTags"