Printers PDF

Printers Printers produce paper copies of electronic files. Government regulations and business policies often require that physical records be kept. This makes paper copies of digital documents as important today as they were when the paperless revolution began several years ago. This chapter prov...

Printers Printers produce paper copies of electronic files. Government regulations and business policies often require that physical records be kept. This makes paper copies of digital documents as important today as they were when the paperless revolution began several years ago. This chapter provides essential information about printers. You will learn how printers operate, what to consider when purchasing a printer, and how to connect printers to an individual computer or to a network. You will also learn the operation of various types of printers and how to install them, maintain them, and to troubleshoot common problems that arise. At the end of the chapter you will learn the importance of a preventive maintenance program for printers and apply the six steps in the troubleshooting process as they pertain to printers. It is important to not only learn about the different types of printers and their components but also to build hands-on skills. In this chapter you will complete a lab performing preventive maintenance on an inkjet printer and a laser printer. You will also work labs on installing and sharing a printer in Windows Computer technicians are often required to select, purchase, and install printers for the users. Technicians need to know how to configure, troubleshoot, and repair the most common types of printers. Most printers available today are usually either laser printers using imaging drums or inkjet printers using electrostatic spray technology. Dot matrix printers using impact technology are used in applications that require carbon copies. Thermal printers are commonly found in retail. Many are used to print receipts. 3D printers are used in design and manufacturing. Printer Speed, Quality, and Color **Speed and Quality** Printer speed is a factor to consider when selecting a printer. The speed of a printer is measured in pages per minute (PPM). Printer speed varies between makes and models. Speed is also affected by the complexity of the image and the quality desired by the user. The quality of printing is measured in dots per inch (dpi). The larger the dpi number, the better the image resolution. When the resolution is higher, text and images are clearer. To produce the best high-resolution images, use high-quality ink or toner and high-quality paper. **Color** The color printing process uses the primary colors cyan, magenta, and yellow (CMY). For inkjet printing, the color black serves as the base or key color. Thus, the acronym CMYK refers to the inkjet color printing process. The figure shows a CMYK color wheel. Reliability and Total Cost of Ownership A printer should be reliable. Because so many types of printers are on the market, research the specifications of several printers before selecting one. Here are some manufacturer options to consider: - **Warranty** - Identify what is covered within the warranty. - **Scheduled** **servicing** - Servicing is based on expected usage. Usage information is in the documentation or on the manufacturer's website. - **Mean time between failures (MTBF)** - The printer should work without failing for an average length of time. This information is in the documentation or on the manufacturer\'s website. When buying a printer, there is more than just the initial cost of the printer to consider. The total cost of ownership (TCO) includes a number of factors: - Initial purchase price - Cost of consumable supplies, such as paper and ink - Pages per month - Price per page - Maintenance costs - Warranty costs When calculating the TCO, consider the amount of printing required and the expected lifetime of the printer. Automatic Document Feeder and Network Scanning **Automatic Document Feeder** An automatic document feeder (ADF) can be found on some laser and inkjet printers which also have the capabilities of copy machines. These are called multi-function devices (MFDs). The ADF is a slot where an existing document can be placed. The machine is then set to make copies of this document. When started, the ADF pulls one page of the document onto the glass surface of the platen, where it is scanned and copies are made. The page on the platen is then automatically removed and the next page in the original document is pulled onto the platen. This process continues until the entire original document in the feeder has been pulled through. Some machines can make multiple copies. Usually these machines can also collate these copies. Depending on the capabilities of the machine, the original document may be placed face up in the feeder or face down. The machine may have a limit as to how many pages can be in the original document. **Network Scanning** It is possible to configure the MFD as a device on the network, just like a networked printer to provide scanning and copying to network locations rather than simply copying to paper. There are three popular places to direct these scans:  - **Scan to cloud** -  The scan is uploaded to a storage location in the cloud such as Google Drive or Apple iCloud. The MFD may have specific cloud locations that are preconfigured or allow you to configure your own. You log in using the scanning prompts either in the software or on the MFD screen if it has one.  - **Scan to folder** - The scan is sent to a network folder on the LAN. The scanning prompts should ask for the path to the folder to which you wish the scan to be saved.  - **Scan to email** - The scan will be created as a file attachment in an email. The scanning prompts will ask for the hostname or IP address of the SMTP server and, often, the email account credentials.  Printer Connection Types A printer must have a compatible interface with the computer to print. Typically, printers connect to home computers using a USB or wireless interface. However, printers may also connect directly to a network using a network cable or a wireless interface. **Serial** A serial connection can be used for dot matrix printers because the printers do not require high-speed data transfer. A serial connection for a printer is often referred to as COM. Serial ports are generally found on legacy computer systems. **Parallel** The data transfer path is wider than the serial data transfer path, allowing data to move more quickly to or from the printer.\ \ IEEE 1284 is the standard for parallel printer ports. Enhanced Parallel Port (EPP) and Enhanced Capabilities Port (ECP) are two modes of operation within the IEEE 1284 standard that allow bidirectional communication. A parallel connection for a printer is often referred to as LPT. Parallel ports are generally found on legacy computer systems. **USB** USB is a common interface for printers and other devices. When a USB device is added to a computer system that supports plug-and-play, the device is automatically detected and starts the driver installation process. **FireWire** FireWire, also known as i.LINK or IEEE 1394, is a high-speed communication bus that is platform independent. FireWire connects digital devices such as printers, scanners, cameras, and hard drives. **Ethernet** Connecting a printer to the network requires cabling that is compatible with both the network and the network port installed in the printer. Most network printers use an RJ-45 interface to connect to a network **Wireless** Many printers come with built-in wireless capability which enables them to be connected to a Wi-Fi network. Some come equipped with the ability to connect to devices through Bluetooth pairing. Inkjet Printer Characteristics Inkjet printers are easy to use and usually less expensive than laser printers. The figure shows an all-in-one device that contains an inkjet printer. Some advantages of an inkjet printer are initial low cost, high resolution, and they are quick to warm up. Some disadvantages of an inkjet printer are that the nozzles are prone to clogging, ink cartridges can be expensive, and the ink is wet for a few seconds after printing. **Ink Cartridges/Paper** Ink cartridges and paper are the primary consumable items in an inkjet printer. Ink cartridges are designed for specific makes and models of inkjet printers. Most inkjet printers use plain paper for printing. Some can also print images on high quality photo paper. Consult your printer's manual for the correct type of ink cartridges and paper to use.\ \ If inkjet printer quality degrades, check the printer calibration by using the printer software. **Print Head** Inkjet printers use ink cartridges that spray ink onto a page through tiny holes. The tiny holes are called nozzles and are located in the print head. There are two types of inkjet nozzles: - **Thermal** - A pulse of electrical current is applied to heating chambers around the nozzles. The heat creates a bubble of steam in the chamber. The steam forces ink out through the nozzle and onto the paper. - **Piezoelectric** - Piezoelectric crystals are located in the ink reservoir at the back of each nozzle. A charge is applied to the crystal, causing it to vibrate. This vibration of the crystal controls the flow of ink onto the paper. Roller Rollers pull paper in from the feeder. **Feeder** The feeder may hold blank paper in a tray or cassette. Some inkjet printers are also copiers. They may have an Automatic Document Feeder (ADF). The ADF holds documents which are fed page by page onto the scanner bed for copying. **Duplexing Assembly** Some inkjet printers can print on both sides of a page. This requires a duplexing assembly which turns a printed page over and feeds it back through the printer to be printed on the other side. **Carriage/Belt** The print head and ink cartridges are located on the carriage which is attached to a belt and motor. The belt moves the carriage back and forth across the paper as the ink is sprayed on it. Laser Printer Characteristics A laser printer is a high-quality, fast printer that uses a laser beam to create an image. Some advantages of a laser printer are low cost per page, high ppm, high capacity, and prints come out dry. Some disadvantages of a laser printer are high cost of startup, and that toner cartridges can be expensive. **Imaging Drum** The central part of the laser printer is its imaging drum. The drum is a metal cylinder that is coated with a light-sensitive insulating material. When a beam of laser light strikes the drum, it becomes a conductor at the point where the light hits it. **Toner Cartridge/Paper** As the drum rotates, the laser beam draws an electrostatic image upon the drum. This undeveloped image is passed by a supply of toner. The toner is a negatively charged combination of plastic and metal particles. The electrostatic charge attracts toner to the image. The drum turns and brings the exposed image in contact with the paper, which attracts the toner from the drum.\ \ The toner cartridge and paper are the primary consumable items in a laser printer. Other parts may also be contained in the toner cartridge. Check your printer's manual for more information. **Fuser Assembly** The paper is passed through a fuser assembly that is made up of hot rollers, which melt the toner into the paper. **Transfer Roller** The transfer roller assists in transferring the toner from the imaging drum to the paper. **Pickup Rollers** Pickup rollers may be located in multiple areas of a printer. They move the sheet of paper out of the tray or cassette, then through the printer during the printing process. **Duplexing Assembly** The duplexing assembly turns a page that is already printed on one side so that it can be printed on the other side.  Installing a Printer When you purchase a printer, the installation and configuration information is usually found on the manufacturer's website. Before you install a printer, remove all packing material. Remove anything that prevents moving parts from shifting during shipping. Keep the original packing material in case you need to return the printer to the manufacturer for warranty service. **Note**: Before connecting the printer to the computer, read the installation instructions. In some cases, the printer driver needs to be installed first before the printer is connected. If the printer has a USB, FireWire, or parallel port, connect the corresponding cable to the printer port. Connect the other end of the data cable to the corresponding port on the back of the computer. If you are installing a network printer, connect the network cable to the network port. After the data cable has been properly connected, attach the power cable to the printer. Connect the other end of the power cable to an available electrical outlet. When you turn on the power to the device, the computer determines the correct device driver to install. Test Printer Functions The installation of any device is not complete until you have successfully tested all its functions. Depending on the printer you have, functions might include: - Print double-sided documents. - Use different paper trays for different paper sizes. - Change the settings of a color printer so that it prints in black and white or grayscale. - Print in draft mode. - Use an optical character recognition (OCR) application. - Print a collated document. **Note**: Collated printing is ideal when you need to print several copies of a multiple page document. The Collate setting will print each set, in turn, as shown in the figure. Some printers will even staple each printed set. Functions for an all-in-one printer include the following: - Fax to another known working fax. - Create a copy of a document. - Scan a document. - Print a document. Configuring Printer Sharing Windows allows computer users to share their printers with other users on the network. Users who cannot connect to the shared printer might not have the required drivers installed. They might also be using different operating systems than the computer that is hosting the shared printer. Windows can automatically download the correct drivers to these users. Click the Additional Drivers button to select operating systems that the other users are using. When you close that dialog box by clicking OK, Windows will ask to obtain those additional drivers. If the other users are also using the same Windows OS, you do not need to click the Additional Drivers button. There are potential data privacy and security issues when sharing printers: - **Hard drive caching** - Cached print files pose a privacy and security risk because someone with access to the device could recover this files and have access to confidential or personal information. - **User authentication** - To prevent unauthorized use of a network or cloud-based printer, permissions and user authentication methods can be used to control access to the printer. - **Data privacy** - Print jobs sent over a network could be intercepted and read, copied, or modified. Wireless Printer Connections Wireless printers enable hosts to connect and print wirelessly using Bluetooth or a Wi-Fi connection. For wireless printers to use Bluetooth, both the printer and the host device must have Bluetooth capabilities and be paired. If necessary, you can add a Bluetooth adapter to the computer, usually in a USB port. Wireless Bluetooth printers also allow for printing from mobile devices. Wireless printers that use Wi-Fi connect directly to a wireless router or access point. Setup is completed by connecting the printer to the computer with the supplied software or using the printer display panel to connect to the wireless router. The printer's wireless adapter will support an 802.11 standard. The devices connecting to the printer must also support the same standard. In wireless infrastructure mode, the printer is configured to connect to an access point. Client connections to the printer go through the access point. In wireless ad-hoc mode, client devices connect directly to the printer. Purposes of Print Servers Some printers require a separate print server to enable network connectivity because these printers do not have built-in network interfaces. Print servers let multiple computer users, regardless of device or operating system, to access a single printer. A print server has three functions: - Provide client access to print resources. - Administrate print jobs by storing them in a queue until the print device is ready for them and then feeding or spooling the print information to the printer. - Provide feedback to users about the state of the printer. Sharing a printer from a computer also has disadvantages. The computer sharing the printer uses its own resources to manage the print jobs coming to the printer. If the computer user on the desktop is working at the same time as a user on the network is printing, the desktop computer user might notice a performance slowdown. In addition, the printer is not available if the user reboots or powers off the computer with a shared printer. Software Print Servers In some instances, the computer sharing the printer is running an operating system that is not Windows, such as Mac OS. In this case, you can use print server software. One example is Apple's free Bonjour Printer Server, which is a built-in service in Mac OS. It is automatically installed on a Windows computer if you install the Apple Safari Browser. You can also download the Bonjour Printer Server for Windows, as shown in the figure, for free from the Apple website. When it is downloaded and installed, the Bonjour Printer Server operates in the background, automatically detecting any compatible printers connected to the network. Hardware Print Servers A hardware print server is a simple device with a network card and memory. It connects to the network and communicates with the printer to enable print sharing. The print server in the figure is connected to the printer by a USB cable. A hardware print server may be integrated with another device, such as a wireless router. In this case, the printer would connect directly to the wireless router, most likely through a USB cable. Apple's AirPort Extreme is a hardware print server. Through the AirPrint service, the AirPort Extreme can share a printer with any device on the network. A hardware print server can manage network printing through either wired or wireless connections. An advantage of using a hardware print server is that the server accepts incoming print jobs from devices, thereby freeing the computers for other tasks. A hardware print server is always available to users, unlike a printer shared from a user\'s computer. Dedicated Print Servers For larger networking environments with multiple LANs and many users, a dedicated print server is needed to manage printing services, as shown in the figure. A dedicated print server is more powerful than a hardware print server. It handles client print jobs in the most efficient manner and can manage more than one printer at a time. A dedicated print server must have the following resources to meet the requests of print clients: - **Powerful processor** - Because the dedicated print server uses its processor to manage and route printing information, it must be fast enough to handle all incoming requests. - **Adequate storage space** - A dedicated print server captures print jobs from clients, places them in a print queue, and sends them to the printer in a timely manner. This process requires the computer to have enough storage space to hold these jobs until completed. - **Adequate memory **- The processor and RAM handle sending print jobs to a printer. If there is not enough memory to handle an entire print job, the document is stored on the drive in the print server and printed from there. This is generally is slower than printing directly from memory. Vendor Guidelines A good preventive maintenance program helps to ensure good quality prints and uninterrupted operation. The printer documentation contains information on how to maintain and clean the equipment. Read the information manuals that come with every new piece of equipment. Follow the recommended maintenance instructions. Use the supplies listed by the manufacturer. Less expensive supplies can save money, but may produce poor results, damage the equipment, or void the warranty. As shown in the figure, most manufacturers sell maintenance kits for their printers. If you do not know how to maintain printing equipment, consult with a manufacturer-certified technician. When servicing toner kits and cartridges, wear air filter masks to avoid breathing in harmful particles. In this chapter, you learned how printers operate, what to consider when purchasing a printer, and how to connect printers to an individual computer or to a network. There are many different types and sizes of printers, each with different capabilities, speeds, and uses. Printers can be connected directly to computers or shared across a network. The chapter also introduced the different types of cables and interfaces available to connect a printer. Some printers have low output and are adequate for home use, whereas other printers have high output and are designed for commercial use. Printers can have different speeds and quality of print. Older printers use parallel cables and ports. Newer printers typically use USB or FireWire cables and connectors. With newer printers, the computer automatically installs the necessary drivers. If the device drivers are not automatically installed by the computer, download them from the manufacturer's website or use the supplied CD. You learned important characteristics and components of the various printer types. The primary components of an inkjet printer are the ink cartridges, the print head, roller, and feeder. A laser printer is a high-quality, fast printer that uses a laser beam to create an image. The central parts of a laser printer are the imaging drum, toner cartridge, fuser assembly, and rollers. Thermal printers use a special thermal paper that becomes black where heated. Impact printers have print heads that strike an inked ribbon, causing characters to be imprinted on the paper. Dot matrix and daisy wheel are examples of impact printers. 3D printers are used to create three-dimensional objects. These objects are first designed using a computer. A variety of media is now available to create these objects. You also learned about virtual printing and cloud printing. Virtual printing does not send a print job to a physical printing device but rather, the print software sends the job to a file or transmits the information to a remote destination in the cloud for printing. Common virtual printing options are print to file, PDF, XPS, or to an image. Cloud printing involves sending a print job to a remote printer that could be at any location connected to the internet. You completed a lab installing a printer in Windows. In the lab you installed a print driver, downloaded and installed an updated print driver and if all was configured correctly, were able to print a test page. After you set up the printer, you had a lab where you shared the device in Windows with other users on the network. At the end of the chapter, you learned the importance of a preventive maintenance program for Printers. A good preventive maintenance program extends the life of the printer and keeps it performing well. Always follow safety procedures when working with printers. Many parts inside printers contain high voltage or become very hot with use. There were labs where you performed preventive maintenance on inkjet and laser printers. Finally, you learned the six steps in the troubleshooting process as they pertain to printers.