Industrial Engineer · phase 1 of 16 · noun

Communication Module

Module that adds a network or serial communication interface to the controller.

The Explain card

Plain English
A communication module adds a network port the CPU does not have on its own. It might speak EtherNet/IP, PROFINET, Modbus or a plain serial link.
Example
An old controller with only a serial port gets an Ethernet card so the SCADA server can poll it. The card handles the protocol and the CPU just sees data.
Why it matters
Each module has a connection limit, and a busy HMI plus remote racks plus drives can exhaust it. The module is also where firmware, IP settings and network faults live, so its status lights are the first thing to read when a device goes quiet.
Hook
The controller's translator, and its bouncer.

Word knowledge

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

In a sentence

The 1756-EN2T communication module in slot 3 of the ControlLogix chassis is assigned an IP address before the remote I/O adapter is brought online.

Why these words
  • communication Latin communicatio, a making common, from communicare, from communis, common names the data-exchange job, so the phrase is about the traffic the slot carries
  • module Latin modulus, small measure, diminutive of modus, measure names the plug-in unit, so the phrase points at a card a technician can seat or pull
Where it came from
Origin
English industrial compound of Latin communicatio (a making common, from communicare, from communis) and Latin modulus, a small measure
Entered the language
1980s
What changed
Communication moved from making something common, through talk among people, to the channel that carries a message. Module moved from a small measure used on a column to a plug-in electronics block. PLC catalogs of the 1980s joined the two as the name of a slot beside the CPU.
How it is spelled
Pattern
Latin communis keeps the double m in communication, as it does in community and communal
Pattern
-ation spells the action-noun ending, as in information and conversation
Pattern
Latin -ulus yields English -ule, so module sits with capsule and globule
Breaks the pattern
Old French wrote comunicacion with one m; English restored the Latin double m
Breaks the pattern
catalogs write both communication module and communications module; the extra s is attributive, not a true plural
Breaks the pattern
the noun phrase stays two words; a hyphen appears only when the pair modifies another noun

Spelled like

  • community
  • communal
  • information
  • capsule
Broken into chunks
  • commun
    • community
    • commune
    • communal
  • ation
    • information
    • conversation
    • invitation
  • mod
    • mode
    • modify
    • modest
  • ule
    • capsule
    • globule
    • granule
What it sits beside

Same subject

Same shape

Rack modules

Communication compounds

Module compounds

Where it sits in the deck

Phase 1: PLC Controller Hardware

The box itself, from processor and rack to the modules that plug into it, because nothing else in the deck lands until you know what a PLC physically is.

Neighbours in this phase