Communication Systems

• Surveillance and Signal Equipment

  Includes fire, smoke, and intruder detection and alarm systems
• Audio and Visual Communication Equipment

  Encompasses telephone systems, intercoms, public TVs, and closed-circuit television (CCTV)
• Time Equipment

  Involves clock and program equipment for time management
• Detectors

  Devices used to detect specific signals such as fire, smoke, or intruders
• Control Unit or Panel

  Central control unit responsible for processing signals and triggering appropriate actions
• Alarm Devices


  Devices that produce audible or visual alerts in response to detected signals
• Wiring or Circuitry


  Electrical wiring or circuitry that connects various components of the communication and signal systems
• Types of Fire Alarm Systems

  • Automatic System
  • Manual System
• Non-Coded Manual Stations


  Stations triggered manually without specific identification at the control panel. An annunciation panel may be added to convert each station into a non-coded indicating zone
• Coded Manual Stations


  Each manual station is coded, and this code is received and processed at the control panel. The code is transmitted audibly on the system gongs, typically comprising 3 to 4 digits identifying building number, floor, and individual station
• Temperature Detector


  The most common type is the THERMOSTAT
• Fixed Temperature Unit


  Triggers a set of contacts when a specific temperature is reached. Available in a one-time non-renewable design with a low melting alloy FUSIBLE PLUG
• Rate-of-Rise Unit


  Activates when the rate of ambient temperature differential exceeds a predetermined amount. Can be combined with the fixed temperature unit in a single housing
• Photoelectric Detector


  Reacts to the obscuration of a light beam by smoke. Ideal for fires producing substantial quantities of smoke and gas, such as those caused by slow-burning plastics
• Ionization Detector


  Operates by detecting ionized particles in the air. Not suitable for detecting fires producing heavy smoke but few particles, like alcohol and plastic fires
• Flame Detectors


  Divided into Infrared (IR) and Ultraviolet (UV) detectors. Primarily used in industrial applications due to their high sensitivity
• Control Unit or Panel


  The control panel's primary function is to energize audible devices (bells, buzzers, gongs) upon receiving a signal from the detector. Additional functions include shutting off oil and gas lines, attic fans to prevent fire spread, and turning off lights. Most units are equipped with an emergency standby battery
• Typical Control Functions in the Fire Alarm Panel

  • Non-Coded Systems
  • Master Coded Systems
  • Zone Coded Systems
  • Dual Coded Systems
  • Selective Coded Systems
  • Pre-signal System
• Pre-signal systems

  Serve to NOTIFY PARTICULAR INDIVIDUALS or teams, allowing them to assess the situation before triggering a broader alarm response
• Fire Alarm System Operation

  1. When an alarm device operates, it initiates two different functions:

  2. An identifying coded alarm located in the maintenance office

  3. A continuous ringing evacuation alarm for the entire building
• Alarm Devices

  • bells
  • buzzers
  • gongs
  • horns
• AC VIBRATING BELL

  The most common type of alarm device, often complemented by a WEATHERPROOF external bell to alert neighbors and passersby
• Open Circuit System

  Typically de-energized and activated only when triggered
• Supervised System

  An open circuit system equipped with a TROUBLE LIGHT to indicate malfunctions. This ensures continuous monitoring and system integrity
• Detection methods in intrusion alarm systems

  • metallic tape
  • micro- and magnetic switches
  • DOOR AND WINDOW MOTION
  • GLASS BREAKAGE
  • Motion detectors, including eyes or LASER LIGHT BEAMS
• Water Flow Switches

  Integrated into sprinkler systems to monitor water flow in sprinkler heads. When triggered by water flow, these switches activate a coded transmitter, initiating a sprinkler alarm
• Sprinkler Alarm

  The alarm code is displayed on a sprinkler annunciator board, also known as a sprinkler alarm panel
• Electrified security door hardware

  Triggers an alarm when a door is opened without authorization, such as exterior doors or doors to restricted areas
• Personnel Entry Control – Card Reader

  • First Level: Entry granted upon insertion of a CARD into an electric device for identification
  • Second Level: Requires simultaneous insertion of a CARD and encoding a THREE-DIGIT NUMBER, restricting entry to authorized card holders
  • Third Level: Involves an ATTENDANT comparing card data with the person's appearance via a computer screen for additional verification
• Watchman's Tour Equipment

  Enables a guard to communicate through an intercom and trigger a general alarm by OPERATING A KEY, typically used for security patrols
• Television Antenna System

  1. Signal Amplification: Amplifies the signal received by the TV antenna

  2. Distribution: Distributes the amplified signals to various wall outlets through a special cable

  3. Booster Amplifier: Required for systems with two or more outlets to enhance signal strength
• Sound Amplifying Systems or Public Address Systems

  1. Microphone: Picks up sound and converts it into an alternative electric current

  2. Amplifiers: Amplify and control the electric current

  3. Loudspeaker: Converts the amplified electric current back into sound, producing sound much louder than the original input from the microphone
• Intercom System

  Comprises one or more master stations (administrative) and several remote stations (staff). Master stations allow selective calling, Remote stations are non-selective when operating through the masters
• Private Automatic Branch Exchange (PABX)

  Based on solid-state technology, capable of handling up to 500 lines and trunks, 4 operator consoles, and over 140 simultaneous conversations
• Operational features of PABX

  • Direct internal and external dialing
  • Consultation hold (ability to hold an outside call while making an inside call)
  • Conference call capability for internal and external units
  • Call transfer and camp-on feature
  • Automatic call back
  • Call forwarding
  • Distinctive ringing for different functions
  • Paging, executive priority, dictation access, personnel location, and other options
• Riser Conduits

  Used in medium-sized installations. Consist of a series of metal cabinets (splicing cabinets) aligned vertically through the building, one on each floor, connected by a vertical conduit
• Riser Shafts

  Required for VERY LARGE INSTALLATIONS. Consist of a series of individual full-length interconnecting closets (SPLICING CLOSETS) aligned vertically, one on each floor, each fitted with a fireproof access door
• Splicing Cabinets or Splicing Closets

  Permit riser cables in the riser shaft or conduit to be spliced or interconnected to cables or telephone wires on various floors
• Floor Conduits

  Connect splicing closets or cabinets to distribution terminal cabinets and to floor ducts, wall outlets, etc
• Single-Line Phones

  Basic telephones without additional extensions or transfer capabilities. Analog units that connect directly to a jack in the wall. Suitable for home offices or small businesses with low phone traffic