Industrial Engineer · phase 2 of 16 · noun

Isolation

Electrical separation that limits unwanted current paths between field circuits, channels, and controller electronics.

The Explain card

Plain English: Isolation is an electrical barrier that keeps one circuit's current from finding a path through another. Optocouplers and transformers pass the signal without connecting the wires.
Example: An isolated input card lets a sensor on a 120 VAC circuit talk to a controller running on 5 V logic. A fault on the field side stays on the field side.
Why it matters: Without isolation, a ground loop between two panels can shift readings, and a wiring fault can put line voltage on the backplane. Channel to channel isolation is also what lets one card read signals referenced to different commons.
Hook: The signal crosses, the current stays home.

How the word is built, where it came from, and what it sits beside in memory.

In a sentence

During commissioning, the technician verifies isolation between the 24 VDC input channels and the PLC backplane before energizing the panel.

How it is built

Where it came from

Origin: French isolation, from isoler, ultimately related to Italian isola and Latin insula, meaning island
Entered the language: 1830s
What changed: It moved from general separation or solitude into technical uses involving circuits, equipment, signals, and energy sources.

How it is spelled

Pattern: A verb ending in -ate forms a noun by dropping the final e and adding -ion, producing -ation.

Spelled like

Broken into chunks

What it sits beside

Same subject

Same shape

isolation devices

Phase 2: PLC I/O and Field Signals

Where the controller meets the machine: discrete and analog signals, the wiring conventions behind them, and the field devices that send them.