What is Intercom System

An intercom system (short for intercommunication system) is a standalone voice or video communication system used within a building or small group of buildings to allow people to communicate with each other without using external phone networks.

Basic Definition

An intercom system lets people talk (and sometimes see each other) from different rooms or locations — for example, between:

  • A front door and inside a house,
  • Rooms within a building, or
  • Different offices or security stations.

 

Main Types of Intercom Systems

  1. Wired Intercom Systems

  • Use physical cables to connect stations.
  • Reliable and secure but harder to install or expand.
  • Common in schools, offices, and older buildings.

 

Wireless Intercom Systems

  • Use radio signals or Wi-Fi.
  • Easier to install; portable units.
  • Common in homes, warehouses, and temporary setups.

 

  • Video Intercom Systems

  • Include a camera and screen for visual identification.
  • Often used in apartment buildings and gated homes.
  • Modern versions integrate with smart doorbells and phones.

 

IP (Network) Intercom Systems

  • Use the internet or a local network (Ethernet).
  • Offer remote access, smartphone integration, and better scalability.
  • Common in modern commercial or security systems.

Deployment location of an intercom system

1. Residential Buildings / Homes

Purpose: Visitor identification, internal communication, gate or door control.

Deployment locations:

  • Main entrance or gate: Video or audio door intercom for visitors.
  • Inside the house: Stations in the living room, kitchen, bedrooms, etc., for room-to-room communication.
  • Garage or back door: For convenience and security.
  • Apartments: One at each unit + main lobby entry panel connected to all apartments.

2. Commercial Buildings / Offices

Purpose: Security, visitor management, internal coordination.

Deployment locations:

  • Reception / front desk: Main control (master station) to communicate with entrances.
  • Entry doors / delivery entrances: Substations with camera and speaker.
  • Manager offices / security room: For internal communication and access control.
  • Parking areas / loading docks: For truck or visitor communication.

3. Schools and Campuses

Purpose: Announcements, emergency communication, room coordination.

Deployment locations:

  • Classrooms: Intercom units for communication with the main office.
  • Hallways / main office: Central master station.
  • Entrance gates: For visitor verification and access control.

4. Industrial or Warehouse Facilities

Purpose: Coordination, safety communication, entry control.

Deployment locations:

  • Production areas / loading bays: For quick internal communication.
  • Security gates: For verifying deliveries and staff entry.
  • Control room: Central intercom hub for monitoring and management.

5. Hospitals and Healthcare Facilities

Purpose: Emergency and service communication.

Deployment locations:

  • Patient rooms: To call nurses or staff (nurse call systems).
  • Operating rooms and wards: Internal staff communication.
  • Entrances: For visitor management and restricted access control.

Intercom Installtion Components

Intercom System Top Vendor

  • Phonomax
  • Crystal
  • NEC
  • Skylink
  • CCL
  • Matrix
  • Panasonic

Telephone Socket Wiring

Telephone socket wiring refers to how telephone lines are connected to wall sockets (jacks) so that phones and other communication devices can access the telephone network.

RJ Connectors — Overview

“RJ” stands for Registered Jack, a U.S. standard (from the FCC) that defines how telecommunication connectors and wiring are arranged.
Each RJ type (like RJ11, RJ14, RJ45, etc.) specifies the physical connector size and pin assignments.

 

RJ11 Color Codes for Two Lines (Optional)

If the cable supports two lines (like in RJ14 / 6P4C):

LineTipRingWire Color
Line 1Pin 4Pin 3Green (Tip) / Red (Ring)
Line 2Pin 5Pin 2Black (Tip) / Yellow (Ring)

Comparison Table

TypePositions (P)Conductors (C)Lines SupportedTypical Use
RJ11621 lineStandard telephone
RJ14642 linesTwo-line phones
RJ25663 linesMulti-line systems
RJ4588Ethernet (LAN)Computer networkin

Quick Way to Remember

  • RJ11: 1 line
  • RJ14: 2 lines
  • RJ25: 3 lines
  • RJ45: Network (Ethernet)