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ACM has no way of determining which objects are in class 1/2/3 for any given device. It can’t prevent an item from being defined with the wrong class. It will allow items for the same object to be defined with multiple class 1/2/3 identifiersmodifiers, even though the item can only be in one of the classes in the device. The user is responsible for determining and defining using the correct class 1/2/3 modifier for the object.
Initializing Class 1/2/3 Items
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The Data Integrity Check Item
There's an The item called DataIntegrityCheck . This item sends a class 0 poll, and updates all items that are activated for the device with the data from that class 0 poll, regardless of what modifier modifiers those items have. This item can be activated to perform data integrity checks on a polling interval. To prevent data integrity checks from being performed during demand polls, check the option “No data integrity check in demand poll” on the Device tab.
Using Class 1/2/3 and Class 0 Items
The class 0 polls that are sent on interval and by demand polls for items with the :c0 modifier will only update the items with :c0, not items with other modifiers. The class 0 polls that initialize class 1-3 items upon activation and after communication failure are data integrity checks that will update all activated items.
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