Tag Components

Introduction

A tag component is a building block used by other tags. A tag component provides common features, for example:

The Analog Data Point Tag is used as a building block for all Analog Data Point Tags.
The PLC Device Tag is used as a building block for all PLC Tags.
The Core Tag is used as a building block for all other tags.

These tag components are supported:

Tag Component	Description
Core Tag	Provides common features in all tags.
Alarm Tag	Used by all tags that raise alarms.
Channel Tag	Provides a communication channel to a device.
Active Channel Tag	An active communication channel that connects to, or sends requests to, a device.
Passive Channel Tag	A passive communication channel that receives commands from an external driver.
PLC Device Tag	Represents a logical connection to a PLC, or Outstation, or Data Source
PLC Scanned Device Tag	Represents a logical connection to a PLC or Device that is scanned at a regular interval.
PLC Device Tag with RTC	Represents a logical connection to a PLC or Device with a real time clock. Fernhill SCADA can synchronize the real time clock of the PLC or device.
Byte Register Block Tag	Represents an array of Bytes in an external PLC Device.
Word Register Block Tag	Represents an array of Words in an external PLC Device.
Data Point Tag	Represents a single data point.
Analog Data Point Tag	Represents a continuously variable data point.
Scaled Analog Data Point Tag	Represents a continuously variable data point (with additional scaling options).
Digital Data Point Tag	Represents a single bit data point.
Word Data Point Tag	Represents an unsigned 16-bit integer data point.
Double Word Data Point Tag	Represents an unsigned 32-bit integer data point.
Long Word Data Point Tag	Represents an unsigned 64-bit integer data point.
String Data Point Tag	Represents a variable length string data point.
GUI Plot Tag	Represents a common reference for all plot types.