National Grid

CTE 224 TERM PAPER ASSIGNMENT

Lecturer in charge : Mr. Taiwo Aderanti GROUP A Mumuni Hammed Abiodun (NCE/F/06/008) Oduyebo Abosede Florence (NCE/F/06/018) Oyerinde Solomon Adewale (NCE/F/06/001) Adenekan Samuel Oluwafemi (NCE/F/06/008) Adesanya Oluwatobi Olutade (NCE/F/06/017)

QUESTION: Explain the types of cables used in: 1. Power supply 2. Communication between systems 3. Communication between system and peripherals Explain methods of cabling for computer networks: 1. Suspended ceilings 2. Raised floors 3. Cable trays

COMMUNICATION CABLE This is use to connect peripheral device to a computer that has a 1 st cable, 2nd cable and a patch unit. The 1st cable encloses set of power line and a set of data lines only. The patch unit include a socket with 1st and 2nd contact. In the patch unit, the set of data line of the 1st and 2nd cables are connected. One of the power line is connected to the 1st contact and other of the power line is connected to the second contact. The 1st cable connect the patch unit in the peripheral device and 2nd cable connect. The patch unit to the computer, when power is apply from an eternal source to the 1st and 2nd contact the power supply from 1st and 2nd contact is connects to the peripheral device. TYPES OF CABLES 1. Twisted cable: this is a two twisted together from a twisted pair. These are several twisted pair in a twisted pair cable.

The choice of a twisted pair cable has a extremely effective way to send high spend signals down the cable because most electrical noise into and radiating from the cable can be eliminated. Signals leaking between wires in a cable be can also be minimized 2. Immunity to electrical noise: the receiving electronics intend to direct only the difference in polarity between the two wire in the twisted pair. Since the electrical noise affect both wires of the twisted pair equally to receiving electronics. Get a twisted signal by rejecting signal on a twisted pair that move toward the same polarity. Cable quality and cable length also play an important role in testing for split pairs. Coaxial cable: This is an electrical cable an inner conductor surround by a tauter insulating layer typically of a flexible material with a high die electrical K instant all of which are surrounded by a conductive layer (typically of a fine woofing wire flexibility or of a thin metal i.e foil) and finally covered with a thin insulating layer on its outside. Then term coaxial cones from the inner conductor of the outer shield

sharing the same geometric axis, coaxial cable is used as a transmission line for radio frequency signals, in application such as connecting radio transmitters and receives with the antennas, cables also use as a transmission lines for radio frequency signal in application as connecting radio transmitter, receiver with computer network (internet connecting and distributing radio television signals. One advantage of coaxial cable over the other type of transmission line is that ideal coaxial cable the electromagnetic field carrying the signal exist only in the space between the inner and outer conductor. This allow coaxial cables runs to be in stored next the metal object without the power losses. It can occur in other transmission lines and its also provides protection of the signal from external electromagnetic interface. It has high frequency performance because of the inner conductor silver plaited material. It also has a braided copper wire forming the shield which make it flexible.

RS-232 standard communication cable: this is a cable which has a standard for serial binary data connecting between a data terminal equipment (CTE). It is commonly use in computer serial port, it can also be use to transfer information between two devices using serial communication and a special wire cable use for connecting two similar computer serial port directly which is known as NULL MODEM. A break pulse is a instrument use in diagnosing problem (out and locate). A breakout pulse as a female RS232 connector and is meant to attach a line.

CABLE TRAYS This is one of the methods of cabling in computer networks that is often preferred to conduit system because of its accessibility and availability to accommodate change. Changing or adding of cables is easy because cable can enter or exit the trays at any point in the system. The cable management raised way system provides organization, security and protection in a structured method of connecting, managing cable and distribution devices for voice data video networks and power. It also brings consistency, quality performance to longer life and less expense to a building network system. It allows routing and support system that can be oriented horizontally or vertically. It provides consistent support throughout the length of the cable and it’s a good method of supporting high bandwidth cables. Cable carry high bit rates do not tolerate bending or sagging because cable trays protect against both.

This is the most expensive give the ease of adding wires, management and security of the wire. It may also become the most economical for long time use. It is used in hallways. Cable trays are wire management solutions for indoor applications. They can also handle more cables than other methods thus reducing the number of way required and the associated material and labor cost. RAISED FLOORS This is one of the methods used in cabling in computer networks. This is a highly effective method of simple hiding on unsightly cables. It is an improve pedestal for a flooring system of the type which utilizes prefabricated base panels installed in side by side relationship to support the series of pedestals. It offers the advantage of convenient access to power and data and communications outlet housed in raised floor boxes. These boxes provide dual service compatibility allowing for the installation of both power to data communication devices. Typically a hole is cut into the raise floor panel. The floor box is set in the opening and secured to the floor and power data communications and service is brought to the box. SUSPENDED CEILINGS A dropped ceiling is a secondary ceiling, hung below the main (structural) ceiling. They may also be referred to as a drop ceiling, false ceiling, or suspended ceiling, and are a staple of modern construction and architecture. The area above the dropped ceiling is called the plenum space, as it is sometimes used for HVAC air return. The plenum space is also very commonly used to conceal piping, wiring, and/or ductwork. A typical dropped ceiling consists of a grid-work of metal channels in the shape of an upsidedown "T", suspended on wires from the overhead structure. These channels snap together in a regularly spaced pattern - typically a 2x2 or 2x4 foot grid in the US, or 600 x 600 mm grid in Europe. Each cell is filled with lightweight "tiles" or "panels" which simply drop into the grid. Tiles can be selected with a variety of materials, including wood, metal, plastic, or mineral fibers, and can come in almost any color. Light fixtures, HVAC air grilles, and other fixtures are available which can fit the same space as a tile. For easy installation. Most tile material is easily cut to allow fixtures in other shapes, such as incandescent lights, speakers, and fire sprinkler heads. The suspended ceiling was originally developed to conceal the underside of the floor above and to offer acoustic balance and control in a room. The acoustic performance of suspended ceilings has improved dramatically over the years, with enhanced sound absorption and attenuation. This is sometimes achieved by adding insulation known as Sound Attenuation Batts (SABs), more commonly referred to as "sound batts", above the panels to help deaden sounds and keep adjacent rooms quieter.

Safety Issues The space above the dropped ceiling is often used as a plenum air return for ventilation systems, requiring only enclosed ducts that deliver fresh air into the room below. Return air enters the ceiling space through open grilles across the ceiling. In the event that the dropped ceiling is used as a plenum, low-voltage cables and wiring not installed inside conduit need to use a special low-smoke and low-toxicity wire insulation which will tend to char and stop burning on its own. This helps to protect building occupants so that they are not poisoned with toxic chemicals sucked through the ventilation system in the event of a fire, and helps to prevent fires from spreading inside the hidden plenum space. This special low-smoke cable is typically referred to as Plenum While networking cable is most the common form of plenum cable, coaxial cable and telephone cable also needs to be plenum-rated for safety. . Advantages Fire Safety If fire safety is a factor, ceiling tiles made from mineral fibers, or fire-rated wood panels can be used within the construction to meet acceptable standards/ratings. These same tiles can provide the needed additional resistance to meet the "time rating" required for various fire code, city ordinance, commercial, or other similar building construction regulations. Fire ratings for ceiling panels vary based on the materials used and preparation of each panel. Ease of modification Another advantage of a dropped ceiling is that the easily-removed ceiling panels offer instant access to the plenum, greatly simplifying repairs or alterations. Wiring and piping installed behind traditional plaster or wallboard ceilings is extremely difficult to modify once the finished ceiling is in place. Wires must either be fished through hollow spaces in the walls behind the finished ceiling, or the ceiling must be demolished in order for wiring or piping changes to be made. In contrast, the tiles and other parts of a drop ceiling are easily removed to allow access to the area above the grid to do any necessary wiring or plumbing modifications. In the event of remodeling, nearly all components the grid can be dismantled and reassembled somewhere else. In business, the drop ceiling is often used in conjunction with hollow steel studs to construct small office spaces out of a much larger cavernous space. Wiring and other services are run through the open ceiling, down through the hollow stud walls, and to outlets in the work areas. If

business needs change, the office spaces are easily dismantled and the overall cavernous space reconfigured with a different floor plan. Disadvantages A panel broken from removal

One disadvantage with this ceiling system is reduced headroom. Clearance is required between the grid and any pipes or ductwork above to install the ceiling tiles and light fixtures. In general, a minimum clearance of four to eight inches is often needed between the lowest obstruction and the level of the ceiling grid. Dropped ceilings are frequently used by slumlords to hide structural and cosmetic damage, loose wiring, insect/rodent infestation, avoiding the need to carry out any repairs or maintenance. Additionally, sometimes walls do not extend past the grid to the actual ceiling. This can present a security risk when used in offices or areas where unauthorized entry may be an issue. As a renovation tool, dropped ceilings are a quick and inexpensive way to repair a ceiling or reduce HVAC costs, however they tend to show their age quickly (and are sometimes discolored by excessive smoking), are damaged easily and are somewhat lacking aesthetically (which is to say, they have a cold and industrial feel - not something engendering a "comforting", "home-y", or "bucolic" feel). This can sometimes be avoided by using panels made of alternative materials, such as plastic or metal. In older buildings that have seen multiple renovations over time, it is not uncommon for a dropped ceiling to have been installed in one renovation and then subsequently removed in another, its installation having been an inexpensive fix to prolong the time between major renovations.