Building Electronics (Fire Detection and Alarm System and CCTV)
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This document provides an overview of electronics engineering applications in building safety and security systems. It discusses fire detection and alarm systems, including relevant laws/standards, fire alarm signals, types of fire alarm systems, and system components like detectors, notification devices, and control panels. It also covers security camera systems, including CCTV fundamentals like cameras, lenses, transmission methods, recording devices, and IP camera anatomy. The document concludes with considerations for detector installation and a discussion of future surveillance trends focused on mobility, storage, security, connectivity and more.
Building Electronics (Fire Detection and Alarm System and CCTV)
- 1. Application of Electronics Engineering in the Building Safety and Security Jed G. Concepcion
- 2. PART I: Fire Detection and Alarm System
- 3. LAWS AND REGULATION / STANDARDS • Philippine Electrical Code • Philippine Electronics Code - Safety • National Building Code of the Philippines • Revised Fire Code of the Philippines of 2008 • National Fire Protection Association (America) NFPA 72: National Fire Alarm and Signaling Code NFPA 70: National Electrical Code
- 5. Fire Alarm Signals Alarm - A signal indicating an emergency that requires immediate action, such as a signal indicative of a fire. 1. Automatic water flow device 2. Manual fire alarm station (pull station) 3. Automatic fire detectors (smoke or heat detectors) Supervisory – A signal indicating the need for action in connection with the supervision of guard tours, the fire suppression systems or equipment, or the maintenance features of related systems. 1. Control valve switch 2. High/low air pressure switch 3. Water tank level and temperature switches 4. Low water pressure for public water supplies 5. Low building temperature switch 6. Alarm line valve position
- 6. Types of Fire Alarm Systems Conventional Conventional fire alarm systems are comprised of initiating and notification zones. The number of initiating zones (initiating device circuits) defines how large the system can be. The zones are generally a specific function (pull station, water flow switch, etc.) or cover a geographical area for smoke and heat detection. Most conventional zones use a two-wire system with an end of line resistor for supervision. Addressable Addressable fire alarm systems assign each initiating device a discrete and unique identification (address). In addition to the address, the panel will usually have the ability to have a tag to further identify the address (i.e. Address 1, Front Lobby, back door, hallway, etc). Some addressable systems consider each point as a separate zone. Addressable devices are similar to conventional devices in that they are either in alarm or in a normal condition.
- 7. Circuit / Loop A circuit comprises an unbroken path (usually a pair of wires) along which an electric current exists or is intended or able to flow. In fire alarm terms this generally means the wiring connecting one or more detectors to the fire panel. Zone A zone is a group of one or more detectors, grouped by their common location or in the case of a collective circuit all of the detectors on that circuit. Another way to describe a zone is one of the following; 1. one or more detectors on an single collective circuit or; 2. one or more detectors, in a common location, defined in software on an addressable circuit. Standards also limit the number of detectors a zone may comprise.
- 10. Circuit Types Fire alarm circuits are wired either Class A or Class B and both have advantages and disadvantages. The Class A circuit utilizes a pair of wires to attach to all of the devices and then a pair returns back to the panel. If a break occurs anywhere in the circuit, every device is still active due to the redundant circuit paths. There are four wires, two supplying power to the front of the circuit and two supplying power from the end of the circuit.
- 11. CLASS B The most common installation is Class B utilizing two wires that connect to each device and an end-of-line resistor for wiring supervision. Unlike Class A circuits, Class B circuits will not fully operate when a wire break occurs. Every device down stream of the break will be unavailable until the wire problem is corrected. The panel will, however indicate a trouble signal
- 12. Typical System component Initiating Device 1. Smoke Detector 2. Heat Detector 3. Gas Detector 4. Beam Detector 5. Flame (UV) Detector 6. Manual Station Notification Devices 1. Sounder / Bell 2. Strobe light
- 13. Smoke Detector Two basic types of smoke detectors are used today: • ionization smoke detector and • Photoelectric smoke detector. 1. Ionization Detector operation - Ionisation smoke detectors use a weak radioactive source (Americium 241) to ionise the air between two electrodes, creating positive and negative ions and so allowing a small current to flow across the chamber. Smoke particles attract these ionised particles, and allow positive and negative ions to recombine, thus reducing the number of ions and hence the current flow. Environmental regulations concerning the radioactive source used in ion detectors means that they are now becoming obsolete, and most major manufacturers are no longer including ionisation detectors in new ranges.
- 15. 2. Photoelectric Smoke Detector Smoke produced by a fire affects the intensity of a light beam passing through air. The smoke can block or obscure the beam. It can also cause the light to scatter due to reflection off the smoke particles. Photoelectric smoke detectors are designed to sense smoke by utilizing these effects of smoke on light.
- 17. Design Consideration: Where Not To Place Smoke Detectors • Excessively Dusty or Dirty Areas • Outdoors • Wet or Excessively Humid Areas • Elevator Lobbies • Extreme Temperatures • Areas with Combustion Particles • Manufacturing Areas • Fluorescent Light Fixtures Avoid placement near fluorescent light fixtures. Electrical noise generated by fluorescent light fixtures may cause unwanted alarms. Install detectors at least 1 ft (0.3 m) away from such light fixtures.
- 18. Beam (D) less that 8 in. consider flat ceiling
- 21. HEAT DETECTOR Heat detectors are normally used in environments where a smoke detector might generate false alarms, for example kitchens or shower rooms. 1. Rate of Rise heat detectors (thermistor) will alarm if the temperature rises very quickly, or if the temperature reaches a set threshold. This type of detector would be the first choice in an environment where a smoke detector could not be used. 2. Fixed temperature detectors give an alarm once the temperature has reached a preset threshold. Fixed temperature detectors operate when the heat sensitive eutectic alloy reaches the eutectic point changing state from a solid to a liquid.
- 28. OPTICAL BEAM DETECTOR Optical beam detectors work on the principle of projecting a beam of light across a room, which is attenuated when smoke is present thus allowing an alarm to be given There are two forms of beam detector: emitter and receiver separate (single path), requiring separate wiring both to the emitter and receiver, and reflective in which the emitter and receiver are mounted in the same box, and the beam is shone onto a reflective material at the far side of the room (dual path).
- 31. CO (Carbon Monoxide) DETECTOR These generally use an electro- chemical sensor to detect carbon monoxide given off by incomplete combustion. They provide reliable detection of incipient fires whilst giving good assurance against nuisance alarms. However the chemical cells used in these detectors have a limited lifespan, and they cannot detect fast burning fires due to the low CO levels produced. Usually installed at the kitchen or cooking area.
- 32. FLAME (UV) DETECTOR Sensitive Ultraviolet sensor that detects the UV rays produced by a flame Not effected by sunlight Dust/corrosion/humidity resistant Standard calibration set to detect a 3cm flame at 6m Effective range 12m Stable and reliable performance
- 33. Manual Call Points A Break Glass Call Point is a device which enables personnel to raise the alarm by breaking the frangible element on the facia. They should be mounted 1.4m from the floor and sited where they can be easily seen. Manual Call Points should be sited on the floor landings 4 of stairways and at exits to open air. Where necessary, extra points should be sited so that the greatest travel distance from any point in the building to the nearest call point does not exceed 30m. A greater number of Call Points may be needed in high risk areas or if the occupants are likely to be slow in movement.
- 35. Sounders / Bell An Alarm Sounder may be a bell or electronic sounder and it must be audible throughout the building. A minimum sound level of either 65db(A) or 5db(A) above any background noise likely to persist for longer than 30 seconds, which ever is the greater, should be produced by the sounders at any point in the building. It is unlikely that more than 65DB will be available if the sound has to carry through more than one door.
- 36. Fire Alarm Control Panel A Fire Alarm Control Panel (FACP), is the controlling component of a Fire Alarm System. The panel receives information from environmental sensors designed to detect changes associated with fire, monitors their operational integrity and provides for automatic control of equipment, and transmission of information necessary to prepare the facility for fire based on a predetermined sequence. The panel may also supply electrical energy to operate any associated sensor, control, transmitter, or relay.
- 42. What are the consideration in Detector’s Installation? (Do’s and Don’ts)
- 43. Do: • Do verify that 2-wire or addressable smoke detectors have been tested and UL listed for compatibility with the equipment to which they are connected. If necessary, contact the manufacturer for this information. • Do locate any end-of-line devices electrically at the end of the circuit, beyond all initiating devices (not at the control unit, except in a Class A installation). On Class A loops, the end-of-line device is built into the panel circuit. An end-of-line device must not be used. • Do use caution when utilizing 2-wire detectors with integral relays, because they may require more power than the initiating device circuit can supply. This could result in the inability of the relay to control auxiliary equipment to which it is connected. • Do follow the manufacturer’s installation instructions to assure proper communication between the smoke detector and the control panel when using wireless detectors. Testing following a fire alarm system installation or the addition to an existing system shall confirm the intended sequence of operation under the most stringent conditions. • Do observe polarity when required. • Do protect detectors against contamination during construction or renovation. • Do follow the manufacturer’s installation instructions carefully.
- 44. Don’t: • Don’t T-tap smoke detectors or circuit conductors, except when specifically permitted by the manufacturer as part of an intelligent/addressable system. • Don’t loop uncut installation conductors around screw terminations. • Don’t exceed the maximum resistance permitted for the initiating device system. • Don’t exceed the allowable number of detectors specified by the equipment manufacturer on any system. Note: Longer than allowed initiating device circuits or Signaling Line Circuit loops may cause a malfunction of the detectors/or the system even though the prescribed number of detectors has not been exceeded.
- 45. Part II: Security System CCTV Camera (Fundamentals)
- 46. What is this?
- 47. What is CCTV? Closed Circuit Television, commonly known as CCTV, is an interesting area of television technology. It is usually used in surveillance systems, but a lot of components and concepts can be implemented in an industrial production monitoring system, or, equally, in a hospital or university environment.
- 48. How CCTV systems are used Public and private CCTV schemes can be deployed for a number of reasons: • Monitoring public areas to detect incidents and to coordinate police responses. CCTV is also used as an aid for enforcing exclusion orders (where an offender is barred from an area). • Recording events for use as evidence and to inform investigations. For instance, on the boundaries of the Parliamentary estate, police on patrol alert CCTV operators of incidents via radio links. CCTV operators then record incidents as they unfold. • Directed surveillance of suspected offenders. • Deterrence of criminal activity – although the evidence for this is inconclusive.
- 49. Components – Cameras Pre-Y2K 1970’s technology were tube based (Vidicon) 1980’s IC Technology brings 1” Charge Coupling Device (CCD) Large and generally 120vAC only Generally Black and White. Color was very expensive Low levels of resolution. Post-Y2K Current CCD technology is ¼” Higher level of resolution. Day/Night Cameras that switch between color and black/white. More analytical features at the camera level. Wide range of sizes/feature/benefits. (small pinhole to dome/PTZ)
- 50. SELECTING THE RIGHT CAMERAS • NIGHT VISION Some cameras come with IR (infra-red) Illuminators that emit a bright light during the night that is not visible to the human eye. Cameras with IR will allow you to see in complete darkness. • INTERNAL / EXTERNAL Depending on where you are going to place your camera either indoors protected from the elements or outside will determine whether you need an internal or external camera. Internal cameras usually are contained within a plastic housing where as an external camera is housed in a weather resistant aluminum casing. • PTZ (PAN TILT ZOOM) Some cameras have PTZ functionality that allows you to control moving the camera left to right (pan) up and down (tilt) and to zoom in closer. These cameras usually come with a controller pad that allows you to control the camera movements using a joystick or the camera can be connect to a PTZ compatible DVR where the camera can be controlled using a standard computer mouse. • TVL (TELEVISION LINES) TVL is similar to resolution where it depicts how much detail the camera can produce. The more TVL the better.
- 51. Pan-Tilt-Zoom Pan-Tilt-Zoom Cameras also known as PTZ cameras are excellent devices to use when you want to 'look around' your surveillance area. PTZ cameras allow you to pan an entire room, tilt up and down and zoom in on anything or anybody within the sight of the lens. PTZ cameras can be set to automatic or manual mode or both. In automatic mode, hundreds of points can be set for the camera to look at. The duration that the camera looks at a given set point can be adjusted from less than a second to as long as you would like.
- 52. Components – Lenses SELECTING THE RIGHT CAMERA LENS A security camera lens size determines the field of surveillance view that the camera provides. Our fixed security camera lenses range from 2.8mm to 16mm. The larger the size of the lens, the more narrow and zoomed in the field of view is. Most of our fixed lens cameras come standard with a 3.6mm or 6mm lens. A 3.6mm lens is designed to provide an approximate 72 degree field of view. If you need precise adjustment to the angle and field of view for your application, a vari-focal lens camera is recommended so that you can adjust the lens to the exact view that you need. Sizing the lens for an application: • Manual Iris – fixed setting for constant light levels. • Auto-Iris – the aperture automatically adjusts as light levels change. • Focal Length – the size of the lens (2.8 – 60mm)
- 53. Components – Transmission RG-59/U Coax cable – traditional method • Baluns can be used to convert video signal to TCP/IP, so that older existing cableplants (RG6/RG59) can be used in today Ethernet environment. • Large Multi-Conductor Phone cable (with Baluns) • Category 5/5E/6 Unshielded Twisted Pair (UTP) Utilize Existing Cable Network – LAN Less space in conduit trays. • Fiber Optic Cable: Longer runs - over 500 ft Immune to strong EMI/RFI signals Large amount of bandwidth • RF Wireless Systems: Cable installation is too difficult Clear line of sight is needed – for transmitter and receivers FCC license may be required (Factors- distance, frequency and population)
- 55. A Digital Video Recorder (DVR) is the recording device which stores all the images onto internal Hard Drives for up to 16 CCTV cameras and view all 16 on a display. Recordings can be played back from all the cameras or one at a time. A user can go back to any time in the recording and playback a recording in a matter of seconds. NVR (Network Video Recorder), a NVR is not limited to be in the same area as your cameras cabling to one section. The unit can be placed virtually anywhere, it simply just needs to be on the same LAN network as the IP based cameras. In terms, a network video recorder are distinct from digital video recorders as their input is assigned on a network rather than a direct connection to a video capture card. Video on a DVR is encoded and processed at the DVR, while video on an NVR is encoded and processed at the camera, then streamed to the NVR for storage or remote viewing. DVR vs. NVR
- 58. IP CCTV System
- 59. Anatomy of a Typical IP Camera
- 60. Future of Video Surveillance 1. Mobility 2. Storage capability 3. Security 4. Connectivity 5. Blind Spot 6. Control Features 7. Cost Efficient 8. Adaptability 9. Quality Standard