Types of tags

Analog
Measures a continuous physical quantity, such as a tank’s volume or a boiler's temperature.

Discrete
Records one of two states for the tag. For example: on/off, open/closed, jam/cleared.

String
Captures a text expression--with no special format--that is treated as a single data item. A string tag could be used to capture the state of a machine; for example: "started", "stopped", "jammed", or "cleared".

Event
Records an instance when a tag meets a preset requirement. For example, a process event tag can let you know when a batch number changes.

System
Reflects a predefined system variable. System tags are used to collect the system's performance data. AVEVA Historian system tags have a "Sys" prefix (for example, SysTimeSec).

Analog summary
Reflects summarized data (minimum, maximum, average, and so on) that is configured to be replicated from one historian to another.

State summary
Reflects summarized data (minimum time in state, maximum time in state, average time in state, and so on) that is configured to be replicated from one historian to another, or stored locally.