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1. ENERGY SOURCES Energy in the form of electrical energy is needed in any electronic equipment to function. Power is normally supplied by the main AC 220V line or batteries. In all electronic equipments there is a power supply which steps down the 220V into a lower voltage needed by the equipment and converts it into direct current (DC). The power supply might have one constant output or a variable one or multiple output with different voltages.
In access control, the power supplies used to power the panel they always have a back up battery in case the main fails, the battery takes over. There are many ways to produce electricity. Electricity is mostly produced by coal fired power generators, nuclear power stations and hydroelectric power stations. In recent years development in the renewable energy have been important due mostly to pollution especially with coil. Among the promising one, there is Fuel cell power and solar panels.
1.1 FUEL CELL
A fuel cell is an electrochemical conversion device. It produces electricity from fuel (on the anode side) and an oxidant (on the cathode side), which react in the presence of an electrolyte.
The reactants flow into the cell, and the reaction products flow out of it, while the electrolyte remains within it. Fuel cells can operate virtually continuously as long as the necessary flows are maintained. Fuel cells are different from electrochemical cell batteries in that they consume reactant, which must be replenished, whereas batteries store electrical energy chemically in a closed system. Additionally, while the electrodes within a battery react and change as a battery is charged or discharged, a fuel cell's electrodes are catalytic and relatively stable. Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen (usually from air) as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include air, chlorine and chlorine dioxide. 1.1.1 FUEL CELL DESIGN A fuel cell works by catalysis, separating the component electrons and protons of the reactant fuel, and forcing the electrons to travel though a circuit, hence converting them to electrical power. The catalyst typically comprises a platinum group metal or alloy. Another catalytic process takes the electrons back in, combining them with the protons and the oxidant to form waste products (typically simple compounds like water and carbon dioxide). 1.1.2 FUEL CELL EFFICIENCY The efficiency of a fuel cell is dependent on the amount of power drawn from it. Drawing more power means drawing more current, this increases the losses in the fuel cell. Most losses manifest themselves as a voltage drop in the cell, so the efficiency of a cell is almost proportional to its voltage. For a fuel cell operated on air (rather than bottled oxygen), losses due to the air supply system must also be taken into account. This refers to the pressurization of the air and dehumidifying it. This reduces the efficiency significantly and brings it near to that of a compression ignition engine. Furthermore fuel cell efficiency decreases as load increases. 1.1.3 FUEL CELL APPLICATIONS A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts. Fuel cells are used in electric and hybrid vehicles and auxiliary power ,notebook computers for applications where AC charging may not be available for weeks at a time, portable charging docks for small electronics (e.g. a belt clip that charges your cell phone or PDA) and Smartphone with high power consumption due to large displays and additional features like GPS might be equipped with micro fuel cells.
1.2 SOLAR ENERGY
Fig1.4: The parabolic dish engine system, which concentrates solar power
Solar energy refers to the utilization of the radiant energy from the Sun and converting them into electricity or any other useful application (heating…).
1.2.1 PHOTOVOLTAIC CELL
A solar cell, or photovoltaic cell (PV), is a device that converts light into direct current using the photoelectric effect. When grouped together in a panel array, they are called solar panel. Solar panels are mainly used to charge batteries for back-up power for home use (mainly in rural areas) or mostly in satellites. A combination of solar panels, storage elements (Batteries) and inverters is widely used as a system for uninterruptable power supply (UPS), where the system is used to supply power in case of a failure in the main power supply. The solar panel charges the battery, which in turn supplies energy to the system after having been converted to AC current by the inverter.
2. HARDWARE SYSTEMS Infrared Passive
Camera
Fingerprint reader Gate motor
Intercom
Manual call point
Boom gate
Turnstile
Proxnet Access control card reader Proxnet Access control mini reader
Proxnet Access control controller
Magnetic lock Proxnet Access control reader interface
2.1.
CCTV CAMERA
Close Circuit TV (CCTV) camera is a technology used in electronic security to monitor and or record certain areas of interest. CCTV is widely used in today developed world due to high rise in criminality and terrorism. CCTV can be used for domestic purposes, having some few cameras monitoring the entrance of one’s gate, the contour of the wall and some other few areas of interest. However in industry, like big stores, banks or national buildings like airports, CCTV is more complex.
2.1.1 THE ELEMENTS OF CCTV THE DIGITAL VIDEO RECORDER (DVR) A Digital Video Recorder (DVR) is the central part of any CCTV system. It works like a personal computer. A DVR has got hard drives to save data and operating software for the DVR which gives a DVR features like: MPEG4 data compression to save disc space, motion detection technology ( record only or send an alarm signal once a motion has been detected), Zooming , event recording or play back and so on depending on each DVR. Some DVR includes a CD-RW to write back-up video footages on a CD. When a CD-RW is not incorporate, most DVR got a USB port for external CD-RW or even for external hard drive if needed.
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The cables from every camera are connected to the DVR depending on the number of channels it got. A 16 channel DVR can only connect 16 cameras. The screen is connected on the output of the DVR. THE CAMERAS A camera is the eye of the system. The camera converts the optical image into an electric signal. There are two main types of cameras: monochrome and color cameras. In these two main types, there are also day and night cameras (which can view in day light and automatically adjust itself to view during the night), infrared cameras (which can see properly during the night because illuminated by an invisible infrared light), IP/TCP camera which has got a unique IP address and
can be connected on a network switch and a PTZ camera also called high speed dome camera which can rotate, zoom and view a wide surface area.
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THE CABLES A coaxial cable, industry standard RG 59 is used to connect various devices of CCTV together. Sometimes an RG 59 power x (RG 59 incorporating two core for power) is used to avoid pulling further cables for power of the cameras. When IP cameras are used, a network cable (Cat 5) is used instead of RG 59. THE MONITOR A monitor for viewing the video footages can be either a monochrome or color screen. A normal cable (RG 59 cable with BNC connector) can be used to connect the screen to the DVR or a computer VGA cable can be used depending on the available connections on the DVR.
2.2.
ACCESS CONTROL
Access control system controls and monitor access to buildings. Instead of the normal key, the door can only be opened when a valid card, tags is approached to the reader or by entering a pin code or if a registered fingerprint is read. Using cards has many advantages compare to using a conventional key. If a Tag or a card is lost, it can be voided from the system, and there is no need to change door locks. For added security, the system can be programmed so that a personal identification number [PIN] is also required before access is allowed or even finger print. The movement of people entering and leaving the building can be monitored and stored Access can be permitted to some people only at a certain period of time. The system can be configured to automatically trigger other systems (switching on the lights, activating CCTV camera…) when someone enters in the building.
2.2.1 THE ELEMENTS OF ACCESS CONTROL CONTROLLER A controller is the main component in access control. It connects to the PC and receives the program of the system. The controller stores all the settings of the system including the date and time, antipass-back status, all the tags or cards which are active in the system. The controller communicates with the rest of the system trough a bus link.
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PUSH BUTTON When a button is pressed, usually a normally open push button, access is allowed. A push button is usually used to open a door from inside. CARD READERS When a valid card or a tag is approached to the card reader access is allowed. A card reader connects to the controller via a bus cable. It reads the tag or card and sends the information to the controller for decision. Some access control system like Proxnet uses reader which have relays inside, the reader has a memory to store the cards which are supposed to open that reader and at the output of its relay, a magnetic lock is connected. When a card is badged, the reader makes the necessary decision to open the door or not, the controller is used only during the programming phase.
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FINGER PRINT READER When someone whose finger print is in the system database is read by the finger print reader, access is allowed. Fingerprint readers usually use a separate bus cable and connect directly to the
computer. The computer is used to enroll fingers in the system, but the fingerprint templates are usually stored inside the fingerprint. KEY PAD When a valid code is entered using the key pad, access is allowed. DOOR CONTACT A small magnetic switch can be mounted on a door to monitor its status. Once the door opens, the switch sends a signal to the controller. Door contacts are usually mounted on fire exit doors or on doors which interlock with others (only one door can open at a time). MAGNETIC LOCK An electromagnet is used with a soft metal plate to lock the door. When the power through the coil is cut, the plate releases the door. The magnetic lock is connected at the normally closed contacts of a relay so that there is a continuous power inside the lock.
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ELECTRIC MOTOR An electric motor can be used to close and open a gate. When activated, a motor will be triggered for a certain time closing or opening the gate. The motor is connected to the normally open contacts of a relay. ELECTRIC BOOM GATE A boom gate is an arm gate. When activated, the motor inside lifts the arm up or pull it down depending on the previous action. Boom gates are usually used in entrance and exit of public parking.
3. PROTECTION Protection is very important in any electronic system. Huge damages in equipments can occur in an unprotected system. CCTV System installations and Access control are vulnerable to lightning induced surge, static and other interferences, particularly on long cable runs and also when system transverse between buildings. Severe damage can occur to cameras, recorders, monitors, controllers, readers and other peripheral equipment that are not adequately protected. Lightning surge protectors are high energy surge arrestors used to limit hazardous energy to safe levels. For ultimate protection always install protectors on each side of the cable.
Lightning surge protector
Figure 3.1 shows a typical lightning protector used in CCTV systems. If the system is struck by lightning, the excess surge voltage is absorbed by this device. In access control, the bus cable used must always be a shielded cable especially if is a long run. The shield of the cable must be connected on ground at one end point only. If connected at both end points, ground-loop currents can be built up in the system which can create more problems. Arc suppression circuitry must be fitted on all doors where there are strike locks or magnetic locks. To minimize damage to the relay contacts, it is recommended that one of the arcsuppression techniques shown here below in Figure 3.2 be used. This element represents the relay contact arc suppression circuitry.
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Power supplies used in the system should be of good standard and should fulfill these requirements: (a) The power supply must provide the correct voltage and be capable of supplying the required current. (b) It is required to adequately ground/earth the system units to a good mains ground. This can be done by connecting a ground lead to the negative (-) terminal of the power input. (c) All mains supplies to the power supply should be protected from high surge voltages by means of Metal Oxide Varistors (MOV), line transformers, or UPS (Un-interruptible Power Supply) systems. (d) Power supplies with battery backup are preferable, to ensure that frequent occurrences of mains ‘brown-outs’ have no effect on the Reader/Controller performance. (e) Ideally ONE power supply should be installed for the set of Readers and Terminals associated with each door. (f) Ideally each high current magnetic lock should be powered from a separate supply (g) It is important that the input voltage to any unit supplied by the PSU should not exceed the value specified in the installation manual for that unit, as damage to the unit may result. (h) Power connection to the units requires conductors with a minimum cross sectional area of 0.5 mm² (0.0008 in²). (i) When units in separate buildings are connected and the earth/ground potentials are different, then a fiber-optic link between the two buildings is necessary.
4. INSTALLATION AND COMMISSIONING 4.1 CCTV CAMERA The installation of CCTV camera system requires the study of the area to be protected to determine which are the areas of great concerns where cameras should be installed. a secure place to be a control room where the screens should be mounted and also a secure place where the DVR will be placed. The cable used for installation is RG 59 or RG 59 power X if normal cameras are used. If IP/TCP cameras are used, a network (CAT 5) cable has to be used.
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When RG 59 cables are used, BNC connectors have to be crimped on both end of the cable to enable connection to the camera and the DVR. When CAT 5 cable is used, RJ45 connectors are used.
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Figure 4.3 shows a typical CCTV camera connection overview.
A maximum of 16 cameras may be connected directly on the video in inputs of this DVR. Depending on the type of monitor used which can be connected at either video out VGA, video out composite or s-video. An optional Audio input if sound is required and an optional Audio out may also be used. The LAN output is reserved for network connection in case there is a need to view the content of the DVR over the network. The RS 485/alarm output is used when a PTZ camera is used it needs command data about rotating left or right or zooming in or out at a specific target. Commissioning a CCTV system is about setting the DVR. Naming the cameras on the screen for easy identification, setting the network IP/TCP address and setting the type of record mode (with motion detector, generating alarms…).
4.2 ACCESS CONTROL Access control is widely used in industry and commercial buildings. Before the installation, a study of the building, the environment and the number of people who will use the facilities has to be determined in order to know which access control system is best suitable. There are many access control systems in the market ranging from single door only to ones which can supports hundred of doors with thousand of cards registered in the system. Some are more suitable in corporate office buildings because of the flexibility and their design while some are more suitable in mining because of their robustness. *
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The figure 4.5 above shows how a Proxnet controller is connected to the system. An RS-232 bus connects the controller to the PC. The out bus from the controller goes to the rest of the network
from reader to reader and ends at the last device where a line terminating resistor is inserted. From each device to the next, polarity of the bus cable must always be respected. Controller Power supply
RS-485/232 Interface at end of network
Twisted pair cable for isolated network
Twisted pair cable for bus RS-485 repeater at end of local network
Readers
Fig 4.5: Overview of Proxnet Installation
Commissioning the system require installation of Proxnet software in the computer, configuring all the parameters, creating all the areas, access level, time zones, create all readers in the system and putting all the cards with the details of their bearers in the system. Once this is done, the information is send to the controller which in turn sends to all the readers.
Fig 4.6: Reader settings
Figure 4.6 shows how readers are configured in proxnet, a reader is given a descriptive name indicate the area where is located the alarm input type and a strike time delay.
Fig 4.7: Card settings
Figure 4.7 shows how users and their card are put into the system. An employee number is typed in, the card number which is a unique number embedded into the card to identify a specific card, the employee name, photo and all his or her details if required and the access level of that card to determine which doors that card can open and which one it cannot open. This procedure is repeated until all employees’ details are entered.
5. DATA COMMUNICATION SYSTEMS In every electronic installation, there are different ways components of a system communicate with each other. Data in electronic is simply electrical signals generated from a controlling unit to the controlled devices to operate, activate or calibrate them. Data can also come from the controlled devices to the controller to inform the controller about their status or acquire input information. Bus is a term generally used in electronic to refer to data communication channel or path.
5.1 BUS SYSTEM IN ACCESS CONTROL Access control system controls and monitor access to buildings. The system is generally comprised with a controller, a PC and door units which can be card readers, fingerprint readers, keypads, magnetic locks or strikers. All these equipment have to communicate with the controller through a bus system.
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There are two data bus types used in access control: A host bus and the terminal bus.
5.1.1 HOST BUS The connection from the host computer to the access controller is the host Bus. The industry standard is either through a Recommended Standard 232(RS-232) also known as DB9 connector or RS-485. Mostly the RS-232 is used as a host bus for serial data communication between the PC and the controller. The maximum distance from the computer to the controller is limited to 25meters but practically to avoid losing data and interference, this distance is kept to maximum of 15meters. If longer distance is needed, an RS-232 to RS-485 converter can be used to increase the distance up to 1000meters.
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Today, RS-232 port is gradually being superseded in personal computers by a USB for local communications. Compared with RS-232, USB is faster, has lower voltage levels, and has connectors that are simpler to connect and use. USB is designed to make it easy for device drivers to communicate with hardware. However, there is no direct analog to the terminal programs used to let users to communicate directly with serial ports. USB is more complex than the RS-232 standard because it includes a protocol for transferring data to devices. This requires more software to support the protocol used The RS-232 cable can be comprised of 3 or 5 wires. If 3 wires are used, which is mostly the case, Transmit (Tx), Receive (Rx) and Ground are used. If 5 wires are used, other wires are used for data request and verification. The baud rate of data has to be set properly on the PC com menu to ensure correct and faster transfer of data. 5.1.2
TERMINAL BUS
The terminal Bus is the bus that links the controller to other devices in the system. The industry standard is through RS-485 which is made of a twisted pair of shielded cable. The maximum distance is 1000meters. If more distance is needed, a repeater has to be used.
When wiring the devices, the shied of the bus cable has to be connected to ground to avoid interference in build up noise in the system especially when the bus is too long. The standard color for bus wires is Yellow for positive and green for negative. Polarity has to be always respected through all the devices on the network.
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The bus wire must always be routed separately from power cables to avoid interference and noise. For a system where the computer is not located in the same place as the rest of the installation, the computer can be connected to an Ethernet adapter with an RS-232 cable to the internet network. From the other location where the rest of the system is located, the system is connected to the internet through an Ethernet TCP/IP interface.
6. TELEMETRY Telemetry is a technology that allows the remote monitoring, measurement, activation, calibration and reporting of information of interest to the operator. Systems that need instructions and data sent to them in order to operate require telemetry technology to be in place. Telemetry can be wireless, or can use cables, computer network (Ethernet) via telephone line or optical fiber link. In CCTV (Closed Circuit TV) Camera systems, Telemetry is used to send video footages captured by different cameras to a remote control room. Companies like banks which require high security and which normally have many branches usually use telemetry to send video data collected to different control rooms or individual cameras to a central main control room through telemetry to allow further analysis of the data, record keeping.
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Figure 6.1 shows an Impro access control system using telemetry. The controller sends data through a modem to an Ethernet link where a remote computer can access data. People entering and living the building or any alarm generated in the system can be accessed through this remote computer. The settings of the system can be changed also with this computer.
6.1 TELEMETRY IN CCTV In CCTV (Closed Circuit TV) Camera surveillance, Telemetry is widely used to report video footages captured by different cameras to a central remote control room especially in companies like banks which have usually many branches. The idea is to see what is happening at every branch and do not let the security officers at branches to temper with the security system. There are software on the market which permits to view the contents of a digital Video Recorder (DVR) remotely. Smart viewer is software that a general computer user can install in his PC to
monitor and/or record the video and audio from a Samsung SHR-2160/2162/2080/2082 DVR in real time through network without going to the site where the DVR is.
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Figure 6.2 shows a typical connection of a DVR to internet link. The LAN (Local Area Network) port of the DVR is connected to a network switch with a cat 5 cable. The network switch is in turn connected to internet. The user has to have internet connection and select the right IP/TCP address is his smart viewer software to access the DVR.
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Once the smart viewer software is opened in the user PC, a screen similar to the one in figure 6.3 is displayed. The screen shows no video image. The user as to select DVR setting on the menu. A screen similar to the one in figure 6.4 will be displayed. To access a certain DVR, the correct IP address (The same as the one configured in that specific DVR), DVR name and port
number. And the user must log in. If all information entered is correct, a screen similar to the one in figure 6.5 below will be displayed showing the pictures in the selected DVR. 3 2 4 4 6 11 12 13 14 8 9 5 7 10
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In the menu, the user have many options, select the number of cameras on the screen (1,4,8 or 16), adjust the contrast or light of the images, record or burn the video on his CD writer or play back old scene by entering the date. If a PTZ camera is installed, there are options to zoom in or out a specific area, viewing left or right.
