PLC Communication, Power Line Communication

Power line communication (PLC) is the latest technique transmitting voice or data at a rapid speed through a power line. The power line communication technology utilizes a power line as a signal transmission channel. This technology makes it possible to perform communication between pluralities of communication devices by connecting each of those devices to a receptacle installed in each room in a house. In the power line communication (PLC), a radio frequency communication signal of a few hundreds Hz to a few tens MHz is transmitted together with an alternating power to a power line supplying the alternating power having frequencies of 50 to 60 Hz to houses, and a private access device receives only the communication signal for communicating. Generally, a PLC communication system comprises a plurality of communication stations connected to a single communication network. Each of the communication stations comprises a PLC for exchanging rapid data through the single communication network. A power line communication modem is a device that makes it possible to use these power lines as a communication line. The PLC modem converts digital data from an information processing unit such as a personal computer

to analog signals, overlaps the signals with the power line of a commercial power source, converts the analog signals inputted through the power line to the digital signals and sends them to the information processing unit. The use of a power line as a communication channel provides a remarkable advantage in that additional expenses are not required for the construction of a new communication channel. The PLC may be applied to various fields such as super high-speed Internet communication, Internet phone, home networking system, home automation and remote metering system just by connecting a plug of a computer to a power source without using LAN or a telephone. Since no new wires are required to implement the function of communication, power-line communication systems greatly reduce the complexity and effort of installation, particularly in building retrofit applications in which it is highly desirable to be able to install an energy control system with little or no alteration of the existing electrical wiring. For further details click here

Wire Stripper

A variety of cables and wires are commonly used for computer, communications, electronic and electrical installations and generally include outer jackets of flat or round configuration formed of rubber or plastic materials. Most electrical wire includes one or a plurality of electrically conductive strands which are surrounded by an insulative coating. In order to make electrical interconnections with the wire, it is necessary to strip the insulation off the wire thereby revealing the electrical strands there beneath. Cable strippers are devices used to strip a portion of insulation from one end of a conductive wire, thereby leaving an exposed conductive element ready to be connected as required. The main function of the wire stripper is to provide the capability of adjusting a stop for the cutters so that, when the device is closed, the cutters cut through the insulation around the wire, but do not nick or damage the wire conductor. Various cable strippers have been made available which serve for stripping the coating off the end of a coated wire and exposing the core in a required length. Wire strippers are essential tools for plumbing and electrical engineering. Wire strippers are used for stripping the insulating layer of coaxial electric cables, bus wires, or electric cords, or cutting the bus wires or electric cords. A coaxial cable stripper is a device convenient for cutting off an insulator from a coaxial cable. After each cutting operation, insulator chips must be completely removed so as not to obstruct further operation of a coaxial cable stripper. For further details click here

Wire Straightener

In various types of manufacturing equipment, it is necessary to supply the equipment with wire that is precisely straight. Typically, wire is manufactured and then reeled or coiled for ease of storage, shipment and handling. Coiled wires are ordinarily annealed slightly so that the wire retains its coiled shape. Wire straighteners have been provided for a variety of applications. Manual cable straighteners have the advantage of being comparatively simple in construction, but they require considerable strength to use, particularly on thick cable. Power operated cable straighteners have generally been large and mechanically complex. Advancements in wire straightening techniques and associated equipment have as the primary aim improvements in the physical and mechanical characteristics, and geometrical parameters of the wire products. A number of wire straighteners are known. These typically involve a bank of rollers which the wire passes through and which are oriented in one plane, followed by a second bank of rollers which act against the wire, and which are oriented in a second plane, perpendicular to the first. For further details click here

Wire Harness

Cables for carrying power, data, control, or other electrical or optical signals are often bundled to simplify their handling, connection, or routing. It is well known to utilize a harness including rings, straps, collars, or an outer sheath around a plurality of cables to form and maintain a bundle comprising those cables. Electrical wire harnesses have been manufactured for years and are used extensively in the automotive, appliance, electronic, and telecommunication industries. Cable harnesses have generally fallen into one or two groups, those which merely secure a number of cables or other work pieces together in a bundle and those which secure one or more work pieces which also incorporate a device for affixing the cable harness to another object. Generally, wire harnesses include at least one multicircuit connector terminated to an insulated multiconductor cable. An electrical wiring harness typically comprises a bundle of individual wires of varying gauges, impedances, and types, all arranged in a particular order. These wire harnesses are bound together in order to facilitate the installation, repair and maintenance of the wires, and the connection of multiple remote systems. Most cable harnesses employ one piece or two piece mass terminated connectors including insulation displacement type electrical contacts. Insulation displacement connectors are well suited for use in automated cable assembly. Miniature cable harness assemblies are commonly used to connect to input/output ports at the rear of integrated circuit cards. A common design for such harness assembly includes a connector frame holding multiple contacts, a circuit board extending rearward of the connector frame, and a stripped cable held to the rear of the board. A wire harness provided on a body of an automobile is attached to various types of electrical and electronic devices. A wire harness is provided on the rear door of an automobile to operate the tail lamp, the rear wiper, etc. A wiring harness for use in an automobile usually comprises a plurality of electric wires and connectors and has a complicatedly-branched geometry. For further details click here

Wire Duct

Cable duct systems are used to route, protect and conceal data, voice, video, fiber optic or power cabling. Electrical wiring of building structures for distribution of electric power generally requires specially insulated wires and/or passing of the insulated wires through a suitable protective conduit. The wiring system is generally enclosed within the wall structure between suitable outlet and power connections. Wire ducts allow custom installation and can be provided within walls or more preferably provided on external surfaces, allowing ready access for reconfiguration, repair, or installation of additional equipment. A wide variety of wiring duct and raceway systems are known for routing various types of wires and cables. A typical wire duct system includes a plurality of raceway runs. The precise configuration of each duct system, including the raceway sizes, lengths and locations, and the number and type of junction enclosures, is determined by site specific wiring layout. Wire ducts are usually made from an resilient synthetic resin material and given a rectangular cross-section. Such a duct has a bottom, a pair of side walls and a top portion which latter can be opened. Wiring ducts in the form of U-shaped channels are known for use in holding, supporting, retaining and distributing conductors in an orderly manner to terminal devices for components located on a common surface area. Such systems often include various straight duct sections and special fittings that adapt the system to numerous configurations. These fittings can be right angle fittings, T-fittings or other shaped fittings designed to route cabling in various directions. For further details click here

USB Connector

Universal serial bus (USB) is a data transmission standard used for connections between devices with USB connectors, such as pen drives, removable hard drives, digital cameras, mice, keyboards, scanners, and printers. The USB interface is configured to support plug-and-play device and is hot-swappable. A connector for use in a USB is called a USB connector. Universal Serial Bus (USB) male and female connectors are commonly employed in electronic systems, such as the computer, consumer or communication industries etc, for signal transmission purposes. A USB cable is used to electrically connect a computer and other apparatuses. For example, input devices such as a mouse and a keyboard are connected through the USB cable to the computer. A USB connector is disposed at an end of the USB cable. The USB connector is inserted into a mount port disposed on a computer. A USB connector is generally comprised of a connector body, a cable connected to the connector body, and an insulative shell covered on the connector body and a part of the cable to secure the connector body and the cable together. In a USB connector, when a plug is inserted into a receptacle, plug terminals is electrically connected to receptacle terminals, respectively. One USB connector is allowed for up to 127 peripherals to be attached including speakers, telephone sets, digital cameras, keyboards, scanners and digital cameras. The USB connection ports are usually positioned near parallel ports or serial ports. A mini USB connector is much smaller than a standard USB connector and is widely used for connecting a hand-held device, such as a digital camera or a personal digital assistant (PDA) to a computer. For further details click here

USB Cable

Personal computers have been fully developed to many utilization applications for many fields. For the diversified applications, there are many peripheral devices are developed to cooperate with the personal computer to achieve some specific functions. A variety of electrical cables are available for connecting printers to devices including computers, computer peripheral devices, network devices, and the like. Examples of cables that transfer both data and power are bus powered serial cables such as universal serial bus (USB) and FireWire type cables. The Universal Serial Bus (USB) is a universal wired interface for serial communications. Universal Serial Bus (USB) connections provide a flexible and adaptable method for connecting peripheral devices to computers. USB provides a computer with a means for communicating with up to 127 devices using a single, standardized communication scheme. A USB cable comprises a cable with a USB connector mounted to an end thereof. A USB connector is disposed at an end of the USB cable. The USB connector can transmit signals at a high speed and has become a standard auxiliary device for computer systems. The USB connector is inserted into a mount port disposed on a computer. When the USB connector is inserted into the mount port, a fastening claw in the USB connector is fastened to a fasten protrusion formed in the mount port, then the USB connector is fastened to the computer. For further details click here

Underwater, Submarine Cable

The cables for communication and electrical power transmission in recent years are more and more installed for longer distances and increasing number of the cables have been laid out upon sea or river beds. The optical fiber has the advantages of low loss, wide bandwidth and light weight and hence is regarded as a promising transmission medium which will succeed a coaxial submarine cable heretofore employed. An optical fiber has a diameter on the order of 125 microns, for example, and is covered with a coating material which increases the outer diameter of the coated fiber to about 250 microns, for example. Coated optical fibers typically are assembled into units or ribbons disposed within a tubular member and enclosed in a sheath system which may take any of several forms. The core portion is enclosed by an outer sheath portion which often is referred to as an over sheath and which includes a plurality of layers of metallic strength members and twine bedding layers and a tar-impregnated twine outer protective wrap. An underwater cable comprises the line cables, repeaters in housings equipped with access cables and joint boxes in which two line cables are connected together or a line cable is connected to a repeater access cable. The joint boxes and repeater housings are covered with a polyethylene jacket sealing and electrically insulating the cable from the surrounding seawater and continuous with the jacket of the line and access cables. Underwater burial machines are used to bury communications cables in the sea bottom in an effort to protect the cables from damage. These machines plow a groove in the seabed beneath a body of water, and they simultaneously lay a cable into the groove which they have plowed. Submarine cable protecting devices are provided to protect the submarine cables installed at locations which are susceptible to seashore waves or sea currents. The submarine cable protecting devices are in a generally cylindrical shape and enclose the submarine cables therein. In many typical submarine optical fiber cables, a supporting metallic structure, called "armor," is employed to protect the fragile optical fibers from excessive tensile and radial forces. For further details click here

Underground Cable

The electric utility industry has been utilizing direct burial power cables for rural or residential electrical distribution. Underground power cables typically consist of a conductive core of a bundle of conducting strands, surrounded by a semi-conducting shield layer, an insulation layer, a second semi-conducting shield layer, a layer of metallic tape or helical concentric neutral conducting strands, and a polymeric jacket or sheath. The conductor may be stranded from multiple wires, or less commonly a solid conductor core may be utilized. Fiber optic cables have become a preferred transmission system for telecommunication and data communication. Fiber optic cable is composed of a bundle of long, thin fibers of glass, plastic or other transparent material closed with a protective sheath. The advantage for fiber optic cable over conventional cable lies in its transmission characteristics. Because of the fiber's thinness and superior attenuation characteristics, a fiber optic cable can carry a much higher rate of information over many more channels than a comparably sized wire cable. Fiber optic cables are generally installed underground inside a conduit. The conduit is often laid in trenches and can extend a mile or more. The conduit generally has a smooth inside diameter throughout its length. Several methods exist for installing the fiber optic cable into the conduit. For further details click here

Twisted-pair Cable

Insulated conductors such as those used in communications cable are often provided as twisted pairs consisting of two insulated conductors twisted about each other to form a two conductor group. Telecommunication networks commonly use twisted pair exchange cables to transmit voice and data signals between central offices and the individual end users. Twisted pair cables are used to distribute signals in a wide variety of applications. The most common traditional use of twisted pair wires and cables is probably for the distribution of telephone signals, analog voice and digital voice. Twisted pair cables are also commonly used in local area networks (LANs) for data communications. Different applications require different performance standards and twisted pair cable classifications have been established for unshielded twisted pair cables by the Electronic Industries Association. Category 1 cables are suitable for POTS, analog voice and digital voice. Category 2 is suitable for 1.44 Mbps ISDN and T1 while Category 3 is suitable for 10BASE-T. Categories 4 and 5 are intended for higher speed applications. Local area networks (LANs) often use unshielded twisted pair (UTP) cables as transmission lines for high frequency communication of data between devices. The UTP cable often has four twisted pairs, each pair including two conductors or wires. In data transmission, the signal originally transmitted through the data transfer media is not necessarily the signal received. The received signal will consist of the original signal after being modified by various distortions and additional unwanted signals that affect the original signal between transmission and reception. Unshielded Twisted Pair cable or UTP is a popular and widely used type of data transfer media. UTP is a very flexible, low cost media, and can be used for either voice or data communications. The wide acceptance and use of UTP for data and voice transmission is primarily due to the large installed base, low cost and ease of new installation. Another important feature of UTP is that it can be used for varied applications, such as for Ethernet, Token Ring, FDDI, ATM, EIA-232, ISDN, analog telephone (POTS), and other types of communication. Category 5 cables (CAT 5) are widely used to transmit signals between computers and various telecommunications, networking and display devices. CAT5 comprises four unshielded or shielded twisted pairs, each of the twisted pairs comprising two individual conductors (one for running a positive signal and one for an inverted signal). Each individual conductor is twisted together to form one pair of conductors. Four pairs of conductors are bundled together to form twisted pair cable. For further details click here

Triaxial Cable

Coaxial and triaxial cables are used in a variety of electronic applications in which electromagnetic shielding is desired to provide noise-free transmission of the signal carried by the central conductor of the cable. It is known that in many applications a conventional cable having a center conductor surrounded by a single flexible coaxial sheath does not have sufficient shielding properties to provide adequate suppression of EMI or RFI interference. Accordingly, a second flexible coaxial sheath which is a good conductor is positioned in concentric relation to the first coaxial sheath which is also a good conductor. These two sheaths are either in electrical contact or separated by an interlayer of dielectric material having a relatively low dielectric constant and a low dissipation factor. When this interlayer dielectric is used, the construction is commonly called a triaxial cable. A triaxial cable is designed to transmit all the video signals as well as the service signals, such as the audio, interphone, remote control and servocontrol signals, by frequency division multiplexing on the internal coaxial structure:. Triaxial cable is commonly utilized to conduct radiofrequency signals at 20 megaHertz with nominal impedance of 75 ohms, such as for transmission of video signals. A standard coaxial cable has a center conductor surrounded by a dielectric, a conductive braid, and a covering jacket. In triaxial cable, two additional layers are provided, an outer braid covered by an outer jacket. The inner conductor is surrounded by a dielectric insulation of controlled thickness so that the intermediate shield braid is coaxial therearound, and another dielectric insulation layer surrounds the intermediate shield and in turn is surrounded by the outer shield braid around which is an outer jacket. Triaxial cables are often terminated by triaxial electrical connectors. For further details click here

Terminal Block

A terminal block is a device that provides or allows an electrical connection between two electrical elements or components. Electrical terminal blocks (terminal junction blocks, junction blocks, or barrier blocks) are well known and widely used in commerce as devices for safely, conveniently and efficiently connecting together one or more pairs of wires or cables. Terminal blocks have long been widely used in electrical utilities, serving as electrical connectors for electrical current power supplies and the like used in relaying, intercommunication and other signaling within power grids. Terminal blocks also have been used as connectors for relatively low voltage electrical power. Terminal blocks are used in a number of electronic systems for connecting wires, conduit, jumpers, shunts, board-to-board cables, and/or other such components to a printed circuit board. Terminal blocks are typically used in the telecommunications industry to connect multiple wire pairs, for example, to connect telephone service wires to telephone company distribution cables. Specifically, an electrical terminal block used in the telecommunications industry typically includes a plurality of interconnected terminal pairs which can be used to connect each individual distribution cable wire on the exchange side to a corresponding individual service wire on the service side. Such terminal blocks may provide interconnections between cables from the central office and subscriber cables or interconnections between a central office cable and a multi-pair cable servicing a local area such as a housing subdivision. A terminal block arrangement includes a pair of electrical terminals arranged in spaced relation on a terminal block body, a conductive terminal bus bar electrically connected between the terminals, and an over voltage protective component irremovably connected with the terminal block body. In certain designs, the wire or conduit can be secured to the terminal block using a screw, spring clamp, quick connect, insulation displacement connection (IDC) terminal, or other suitable fastening means. For further details click here

Telecommunications Cable

Telecommunication cable designs vary according to the role which the cables are meant to fulfill. A typical telecommunications cable generally comprises one or more conductors, e.g., copper or glass fiber, in a cable core that is surrounded by at least two layers of polymeric material including an insulating layer and a jacketing layer. A telecommunications cable is constructed with a core having a multiplicity of twisted units of conductors, each unit conventionally being a twisted pair of conductors. A core may be typically formed as a single core unit of twisted pairs or larger cores. Telecommunication systems employing optical fibers as the transmission medium have become widespread because of their wide bandwidth, relatively low optical loss, and the development of optical amplifiers that do not require conversion of the optical signal into the electrical domain for amplification. A fiber optic cable typically includes a fiber or fibers, a buffer or buffers that surround the fiber or fibers, a strength layer that surrounds the buffer or buffers, and an outer jacket. Optical fibers function to carry optical signals. Because the optical fiber transmission elements are delicate, the telecommunications cables are provided with members which are designed to protect the optical fibers. Thus an optical fiber includes an inner core surrounded by a cladding that is covered by a coating. Buffers typically function to surround and protect coated optical fibers. Strength layers add mechanical strength to fiber optic cables to protect the internal optical fibers against stresses applied to the cables during installation and thereafter. For further details click here

SMA Connector

Coaxial connectors for radio frequency (RF) signals are typically used with a coaxial cable containing an external conductor/shield surrounding one or more internal conductors. The coaxial connector functions to align and provide an electrical path to the respective ends of the conductors while providing a continuous shield to minimize RF leakage. Coaxial connectors at an interface between a PCB and the coaxial cable enable the individual PCB to be connected and disconnected during assembly and/or test, as well as for maintenance and replacement purposes once the PCB has been deployed. A variety of classes or series of standard and semi-custom coaxial connectors are in widespread use including, SMA, SMB, SMC, SSMA, 3.5-mm, and 2.4-mm, 1.85-mm connectors. Such connectors are commonly used to designate operation of the subminiature connectors in different frequencies (e.g., of about 18,4 and 10 GHz, respectively). Subminiature coaxial connectors (SMA) are commonly used as high performance subminiature connectors at microwave frequencies. These connectors are used by those skilled in the art with coaxial cables. The SMA connector includes a female portion and a male portion. The male portion contains the conductor interface and a threaded nut used to engage the female portion. For further details click here

SCSI Connector

The Small Computer System Interface (SCSI) is a communications protocol standard that has become increasingly popular for interconnecting computers and other input/output devices. Modern electronic devices rely upon interconnection of various components to form circuits. These electronic components are typically mounted on printed circuit boards, which have copper traces routed along and within the circuit board that provide electrical connections between components mounted to the circuit board. Personal computers provide today's users with the power to communicate with other networked users, share information and access data from peripheral devices. To achieve high performance data transfer interfaces between the host computer system and a given peripheral device, computer users typically use hardware that can take advantage of the small computer system interface (SCSI) protocol. The SCSI bus is a system level interface that essentially provides a complete expansion bus where peripherals such as data storage devices may be connected. The SCSI bus functions as a separate bus whereby SCSI devices can exchange data among themselves without the intervention of the host computer's microprocessor. A small computer standard interface (SCSI) specification defines a number of parameters to interface peripheral devices to computer systems. Typically, computer systems implementing the SCSI specification contain an internal bus. In addition, computer systems contain a connector so that the internal bus may be expanded external to the computer system. The expansion of the bus permits interfacing of a number of peripheral devices. Once a computer is provided with SCSI capabilities, the user is able to connect either internal or external SCSI peripheral devices to the computer. Internally, SCSI ribbon cables are used to interconnect the peripheral devices to the computers controller card or a motherboard's connector. Externally, SCSI peripheral devices can be coupled to the computer's connector receptacle via an external SCSI cable. SCSI (Small Computer System Interface) connectors provide a standard interface between computers and internal/external SCSI peripheral devices, such as fixed and removable storage drives, scanners, compact discs, etc. For further details click here

SCSI Adapter

Small computer system interface (SCSI) is a set of standard electronic interfaces that allow personal computers to communicate with peripheral hardware such as disk drives, tape drives, CD-ROM drives, printers scanners faster and more flexibly than previous interfaces. The Small Computer System Interface (SCSI) defines an input/output bus and logical interfaces supporting the bus of interconnecting computer and peripheral devices. Small computer system interface (SCSI) allows for the connection of up to fifteen peripheral devices to a single controller called a "SCSI host adapter" of a computer device. SCSI peripherals are daisy chained together using a second port to connect each device to the next device in line. In addition to faster data rates, SCSI is more flexible than earlier parallel data transfer interfaces. The SCSI standard can transfer data at up to 80 megabytes per second (MBps). SCSI allows for the connection of multiple devices to a single SCSI host adapter. Typically, this host adapter is connected to a motherboard in a computer through a Peripheral Component Interconnect (PCI) slot. With this type of system, peripherals are daisy chained together. These peripherals have a second port used to connect the next device in line. Usually, the SCSI host adapter sent three messages to the target and then changed the SCSI bus phase to phase Command. A sequencer on the host adapter moved a CDB from a sequencer control block (SCB) that was received from a host to a DMA channel that in turn transferred the CDB over the SCSI bus to the SCSI target. For further details click here

Serial ATA Connector, SATA Connector

Parallel ATA (Advanced Technology Attachment) and parallel SCSI (Small computer System Interface) are two dominant disk interface technologies in past long period. The parallel ATA (Advanced Technology Attachment) specification has defined the standard storage interface for PCs. Parallel ATA provides low cost, broad operating system support, and steady evolution. Over time, parallel ATA has continuously evolved to support higher speed and performance. While the parallel ATA interconnect has been the dominant internal storage interconnect for desktop and notebook computers, ATA compliant interfaces have a number of limitations that are exhausting their ability to continue increasing performance. Serial ATA (SATA) is a point-to-point connection and allows multiple ports to be aggregated into a single controller that is typically located either on the motherboard or as an add-in, RAID card. Serial Advanced Technology Attachment (SATA) allows the interface to operate at higher speeds without the problems associated with a parallel interface at higher speeds. As computer processor performance has increased, so have the read/write data rates of hard disk drive heads and media. SATA eliminates bottlenecks that occur in parallel AT interfaces. Serial ATA abandons the parallel concept in favor of a serial interface where only one bit is transferred per time. This allows the interface to operate at higher speed without the problems associated with a parallel interface at higher speed. Serial Advanced Technology Attachment (SATA) provides an interface to attach peripheral and other electronic devices to host computers or other host devices. A typical SATA system includes a host, a device and a communications medium that connects the host to the device. The host typically includes processing circuitry, volatile high-speed memory, and a host-side controller or concentrator. The device is typically a data storage unit. The Serial ATA communications cabling connects the host-side controller to the device and carries signals between the host and the device in accordance with the Serial ATA interface specification. A standard parallel ATA interface uses a 40-pin connector and a bulky flat ribbon cable that is becoming unable to accommodate further growth in the data transfer capacity of the interface. The serial ATA connectors according to the Serial ATA standard are featured in fewer electrical contacts than other conventional electrical connectors and are relatively tiny in configuration. Generally, the serial ATA connector comprises an insulative housing, a plurality of contacts assembled to the housing, a plurality of wires electrically connecting with the contacts, and a latching device for providing a reliable mechanical and electrical connection with a complementary connector. A SATA interface can accommodate growth in data transfer capacity and that uses a significantly smaller 7 conductor connector. The connector includes a receiving differential pair of conductors and a transmitting differential pair of conductors. The remaining three conductors are ground connections. For further details click here

SATA Cable

Today, computers are routinely used both at work and in the home. Typically, each host computer has a storage media such as a disk drive. A hard drive is connected to the computer by way of an interface, usually a controller card, a cable, and some software protocols. The disk drive is typically connected to the host computer via a cable and a cable connector that connects to a device connector of the disk drive. For compatibility, the connectors and interface protocol are standardized. Accordingly, the cable, cable connector, and device connector should comply with the same interface standard. One type of hard drive interface used today is an integrated drive electronics (IDE) interface. This is also known as an advanced technology attachment (ATA) interface. ATA is the actual interface specification for the IDE standard. The IDE/ATA standard is a parallel interface whereby multiple bits of data are transmitted at one time across the interface simultaneously during each transfer. A parallel interface allows for high throughput, however, as the frequency of the interface is increased, signaling problems and interference between signals become common. Parallel ATA allows up to two devices to be connected to a single port using a master/slave communication technique. One ATA device is configured as a master and the other slave. Both devices are daisy-chained together via one ribbon cable that is an unterminated multidrop bus. This bus or connection is typically referred to as a parallel channel. As demand for higher transfer and storage bandwidths increases, the parallel ATA is nearing its performance limit. For this reason, serial ATA (SATA) was developed as a next generation ATA specification. Serial ATA is a computer bus primarily designed for transfer of data between a computer processor and hard disk and has at least three advantages over Parallel ATA, namely speed, cable management, and Serial ATA's ability of being hot swappable. Serial ATA may combine software transparency, low cost, scalability, and design flexibility to overcome the limitations of parallel ATA. Point-to-point data rates of 1.5 Gbps may be attainable with Serial ATA. SATA connects each of the two drives with individual cables in a point-to-point fashion. Software drivers for parallel ATA have to be modified to accommodate serial ATA. To support Serial ATA communications, a power supply cable typically runs from a power controller of the host to the device to carry power supply and ground signals from the power supply to the device. Additionally, a separate SATA communications cable typically runs from a controller or concentrator of the host the device to carry information between the host and the device. The Serial ATA cable generally includes seven lines: two transmit lines for carrying a differential mode transmit signal, two receive lines for carrying a differential mode receive signal, and three ground lines. For further details click here

RJ11, RJ45 connector

Industry standard RJ-type jacks for receiving mating modular plugs have become extremely common and are found in virtually every telecommunications and data communications system worldwide. The RJ-series connector, such as the RJ-11 and RJ-45 connectors, represents such a standard connector. The standard RJ-series modular connector includes a plug or contact block and a jack or socket having a certain number of mating contacts. The plug includes a small block shaped body typically having pressure activated blades which can be crimped on to a cable. RJ-45 connectors were originally developed to terminate flat telephone cable and are very well suited to that application. In recent years these connectors have also been used for data communications purposes including terminations of unshielded twisted pair (UTP) cable for high speed data transmission. An RJ-45 cable is typically available having an RJ-45 connector attached to each end. A modular jack assembly, known as an RJ-45 connector assembly or an RJ-11 connector assembly, comprises a plug connector and a mating receptacle connector. An RJ-45 connector assembly used for a network communication has dimensions larger than those of an RJ-11 connector assembly which is used for a telephone. The RJ-45 connector has a larger width dimension than the RJ-11 and is configured to facilitate eight connections. The RJ-11 is configured for four connections but has a form factor to accommodate six. RJ-45 sockets are mounted in ports or interfaces in electrical appliances such as computers to connect signals transported electric wires to the appliance. The socket can be integrated into a circuit board and can be accessed through a port in the housing or enclosure of associated equipment or can be molded directly into an enclosure and wired to a circuit board. The interior surface of the socket includes a receiving notch for accepting the retention clip of the plug so as to mechanically secure the plug within the socket. Once the retention clip has snapped into place within the receiving notch through a flexing action of the retention clip away from the body of the plug, the plug is firmly held in place providing secure mechanical and electrical coupling. For further details click here

Ribbon cable

Electrical cables in a variety of configurations have been available for an extended period of time. One of those varieties is ribbon cable. Ribbon cables are flat, flexible cables containing a plurality of electrical wires that are aligned in a row. Ribbon cable is commonly used to interconnect computer motherboards with other components within a computer system and it can also be used to interconnect personal computers to other devices in a network. One typical application is to use ribbon cable to interconnect component devices that are linked in a SCSI interface network. Ribbon cable is comprised of a plurality of conductors that are positioned so as to be coplanar. The conductors are typically embedded within insulation material that provides some protection to the conductors of the ribbon cable. Fat ribbon cables are constructed to have a plurality of spaced-apart conductors, with a common dielectric insulating jacket surrounding the conductors and filling the spaces therebetween to form webs of insulation material. In ribbon cable, a plurality of conductors are disposed side by side to yield a cable with a roughly rectangular cross-section as opposed to the round cross-section of ordinary cables. The rectangular cross-section permits the use of the ribbon cable in applications where one or two dimensions are constrained. A standard ribbon cable connector includes a plurality of female slots that are arranged in the same predetermined pattern as the pins or teeth on the hardware device. The pin slots are sized to slidingly receive the pins on the hardware device. Electrical connectors on the ends of flat ribbon cables and on printed circuit boards are mated to permit communication of signals within the system. Signals containing large amounts of data are rapidly transmitted through the ribbon cable and the electrical connector assemblies joining the cable to system components. For further details click here

Power strip

Power strips are commonly used to distribute a power input to multiple outlets, i.e., jacks, sockets, or female connectors. Power strips enable multiple electrical appliances and equipment to draw power from a single source such as a wall outlet. Power strips are useful when there are not enough built-in power outlets nearby to support all of the devices and equipment that need power. For example, power strips are commonly used in households to supply power to items such as televisions, stereos, compact disk (CD) players, lights, lamps, cable boxes, computers, computer monitors, computer printers, alarm clocks, sweepers, and other various types of household items. A typical power strip has an elongated housing with multiple receptacles uniformly disposed in a single row along a top surface of the strip. Each receptacle is configured to receive an electrical plug of an appliance or equipment. The inside of the power strip housing may further include a surge protection circuitry and/or other circuit breaking devices. An extension cable extends from inside the casing to for example a plug adapted to connect to the wall outlet for supply of electricity from the wall outlet to the power strip or the parts or elements mounted therein. Hot contact and neutral contact and/or ground contact are provided on the casing for each of the outlets to receive a plug therein. Optionally, each outlet in the power strip may include a third female contact receptacle which is electrically connected to the ground line of the power cable, the third female contact receptacle being disposed within the interior cavity and accessed through an associated opening formed in the top of the casing. In addition to the receptacles on the top surface, ON/OFF powers switch and LED indicators for power and surge protection may also be found. For further details click here

Power cable

Power cables are low, medium or high-voltage electrical cables with plastic-insulated conductors. The conductors can be made of copper or aluminum. A power cable is generally constituted with a cable conductor configured as a bundle of core wires for transmission of required electric power, a cable insulator configured for insulation about the conductor and made of, for example, a plastic material such as bridged polyethylene, a cable screen configured for electric screening about the insulator, and a cable outer cover configured for coverage and protection about the screen. In power cables the electric conductor is usually coated first with an inner semiconducting layer followed by an insulating layer, then an outer semiconducting layer followed by water barrier layers, if any, and on the outside a sheath layer. Semiconductive shields have been used in power cables as shields for the cable conductor and insulation for many years. A conductor shield is typically extruded over the cable conductor to provide a layer of intermediate conductivity between the conductor and cable insulation in the power cable. A shield is also typically provided over the insulation. The outer semiconducting shield can be either bonded to the insulation or strippable, with most applications using strippable shields. The inner semiconducting shield is generally bonded to the insulation layer. Additional layers within this construction such as moisture impervious materials are often incorporated. Paper insulated cable comprises an inner core containing, usually, three or four current carrying conductors. The conductors are insulated from each other and are surrounded by an insulation comprising oil impregnated paper. A metal sheath, generally of lead or aluminum, surrounds the insulation to protect the core from moisture. Surrounding the metal sheath is a layer of armor which provides longitudinal strength and mechanically protects the metal sheath. A polymer insulated power cable consists of one or more insulated conductors. The conductors may be solid metal or of stranded construction and are typically of copper or aluminum. The insulating polymer is typically cross-linked polyethylene, polyvinyl chloride or ethylenepropylene rubber and is generally applied by extrusion. Individual insulated conductors are known as cores. Numbers or cores are layed together to form a cable. Electric power cables for medium voltages (6-69 kV) and high voltages (>69 kV) normally include one or more metal conductors surrounded by an insulating material like a polymer material, such as an ethylene polymer. A typical low voltage power cable is constructed of metal conductors insulated with a polymeric material. These elements are generally twisted to form a core and are protected by another polymeric sheath or jacket material. In certain cases, added protection is afforded by inserting a wrap between the core and the sheath. For further details click here