Tag

How it is used

Used every day by automation programmers. You create, name, map and monitor tags, and HMI objects are linked to PLC tags. Good tag names and a clean tag list make programs much easier to maintain. Older systems use addresses instead, such as I0.0 or N7:0.

Example sentences

1. Link the button on the HMI to the tag Robot_Start in the PLC.

2. Can you add the new tags to the tag list and send it to the SCADA team?

Common collocations

• tag name
• tag list
• PLC tag
• monitor a tag
• tag database

Related terms

• PLCShort for programmable logic controller: a rugged industrial computer that reads inputs from sensors and switches, runs a control program and drives outputs such as motors, valves and lamps.
• HMIShort for human-machine interface: the touch screen or panel operators use to see a machine's status, start and stop it, change settings and read alarms.
• SCADAShort for supervisory control and data acquisition: software that collects data from PLCs and devices across a plant, shows it on screens and lets operators monitor and control the process.
• I/OShort for inputs and outputs: the signals a controller receives from sensors and buttons, and the signals it sends to valves, motors, lamps and other devices.
• function blockA reusable piece of PLC code with its own inputs, outputs and memory, used to control one type of device, such as a motor, valve or conveyor, many times in a program.

This word in other fields

The same English word can have a different meaning in another field:

• tag · Software Engineering
• tag · Web Development
• tag · Social Media & Content Creation

More terms: PLCs and Industrial Control

• ladder logic
• relay
• analog signal
• scan cycle
• structured text