Adding a counter OPC item

  1. Select Configuration > OPC > OPC Items. The OPC Items screen is displayed
  2. Click Add. The Add window is displayed.
  3. Specify this information:
    OPC Item Type
    The type of OPC item must be set to Counter.
    Tag Name
    The name of the OPC item.
    Address
    The address of the tag in the OPC server.
    Description
    The description of the OPC item.
    OPC Server
    The OPC server used for reading and writing tags in the from and to fields.
    OPC Group
    The OPC group to which the tag is assigned.
    Machine
    The machine associated with the OPC item.
    Offset
    An offset value applied to incoming OPC data. The offset value is not applied if this field is set to 0.
    Counter Method
    Indicate whether the OPC value is derived from a property or formula. Possible values:
    • Properties: The OPC value is derived from the OPC server. If this value is selected, a low value and a high value must be specified. Based on the specified values, the application calculates rollovers correctly.
    • Formula: The OPC value is calculated based on an expression that defines how to determine the value of the OPC item using other OPC items.
    Multiplier
    A multiplication factor applied to the OPC item for scaling. The multiplier is not applied if this field is set to 1.
    Counter
    Indicate whether the OPC counter is a production or spoilage counter. Possible values:
    • Production: Allows you to track production counts. If this value is selected, you must select the value in the Production Counter field.
    • Scrap: Allows you to track scrap counts. If this value is selected, you must select a value in the Scrap Reason field.
    Production Counter
    The production counter associated with the counter type. This option is only available if the Counter is set to Production.
    Scrap Reason
    The scrap reason associated with the counter type. This field is enabled only if the Counter Type field is set to Scrap option.
    Acceptable Rate Of Change
    The maximum allowed rate of counts per second. Rates of change evaluated below this threshold automatically ignore counter values. This field can be left blank if needed.
    Delta Mode
    Indicate how the changes to the delta values are to be interpreted in the OPC counter. Possible values:
    • Interpret negative movement as roll-over: The counter is never negative and the rollover value (High Value) is used to calculate the difference. If the counter is manually reset, a large incorrect number will be calculated as the value as the system will rollover at the rollover value (High Value).
    • Allow negative movements: Allows application to record negative counts.
  4. Click OK.