CTEC1465 A+ Content. Objective 4.1 Explain the differences between the various printer types, and summarize the associated imaging process.

Transcription

1 CTEC1465 A+ Content 6 Printers Complete this unit, and you'll know how to: A B C Explain the various imaging processes that printers use. Install and configure a printer. Perform printer maintenance. 6.1 Topic A: Imaging Process Objective 4.1 Explain the differences between the various printer types, and summarize the associated imaging process. Laser o Imaging drum, fuser assembly, transfer belt, transfer roller, pickup rollers, separate pads, duplexing assembly o Imaging process: processing, charging, exposing, developing, transferring, fusing and cleaning Inkjet o Ink cartridge, print head, roller, feeder, duplexing assembly, carriage and belt o Calibration Thermal o Feed assembly, heating element o Special thermal paper Impact o Print head, ribbon, tractor feed o Impact paper CTEC1465_aplus_Printers.docx Page 1 of 23

2 6.1.1 Inkjet printers Explanation Inkjet printers, also known as ink dispersion printing technology, produce images by forcing ink through tiny nozzles and onto the paper. Each nozzle is approximately 50 to 60 microns in diameter. The ink is forced through the nozzles through either of two basic methods: thermal bubble or piezoelectric bubble. Exhibit 6-1: An ink jet printer Thermal bubble technology Thermal bubble technology heats the ink, which vaporizes it, creating a bubble. The bubble protrudes out through the nozzle and sprays onto the paper. When the bubble bursts, it creates a vacuum, which draws more ink from the cartridge into the print head, preparing it to create another dot Piezoelectric technology Piezoelectric technology creates a bubble with a piezo crystal behind each nozzle. An electrical current sent to the crystal causes it to vibrate. When it vibrates inward, it releases ink onto the paper; when it vibrates outward, it pulls ink from the cartridge Ink cartridges Ink cartridges are the reservoirs that hold ink for inkjet printers. The number of cartridges used varies, but most printers have a black cartridge plus a color cartridge with compartments for yellow, cyan, and magenta. The entire color combination is often referred to as CYMK (cyan, yellow, magenta, and black). Some printers have separately replaceable cartridges for each of the colors. Some have more colors than these three basic ones. Some inexpensive printers don't have a separate black cartridge. Instead, when black is required, they mix all three colors together to produce a dark color. CTEC1465_aplus_Printers.docx Page 2 of 23

3 Exhibit 6-2 shows two inkjet cartridges: one black, and one containing cyan, yellow, and magenta inks Print heads The print head for an inkjet printer is usually part of the ink cartridge. Because this is the printer part that wears out the soonest, having it replaced each time you replace the ink means that you always have a good print head. It also makes the cartridges more expensive. If the print head is part of the printer rather than the cartridge, the cartridges are usually less expensive, but after a couple of years, you might notice that the print quality has degraded. Exhibit 6-3 shows the print head on an inkjet cartridge. The print head moves across the page on a small carriage pulled by a belt, printing columns of pixels. To increase the resolution, a second pass is made across the page to overwrite between the existing dots. On some printers, printing occurs on both passes across the page -- left to right and right to left. On others, it prints in only one direction, and as the stepper motor advances the page, the print head moves back across the page to begin printing the next line Laser Printers Explanation Laser printing is an electrostatic digital printing process. It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a negatively charged cylindrical drum to define a differentially-charged image. The drum then selectively collects electrically charged powdered ink (toner), and transfers the image to paper, which is then heated in order to permanently fuse the text and/or imagery. CTEC1465_aplus_Printers.docx Page 3 of 23

4 Toner cartridge A toner cartridge contains: A hopper filled with toner. Toner is a fine powder composed of plastic, iron, and carbon particles. An electrophotographic (EP) drum covered with a photosensitive coating that holds a static charge until exposed to light. A blade for removing used toner from the drum. A corona charging assembly, which applies a static charge to the drum after an image has been printed. Exhibit 6-8: Toner cartridge, photographed from top Output capacity varies from manufacturer to manufacturer. Check the specifications for the printer you're considering to determine the lifespan of a toner cartridge for that printer. CTEC1465_aplus_Printers.docx Page 4 of 23

5 Power supplies A high-voltage power supply (HVPS) converts standard 120 volt AC current into high-voltage electricity used by the electrophotographic process. A DC power supply (DCPS) is used to power components, such as the laser and fuser, that don't require high voltages. The DC power supply provides +5V and -5V for the printer's logic circuitry and +24V for the paper transport motors Paper control and transport assembly Paper is moved through the printer by a series of rollers. Some of the rollers simply guide the paper from one location to another, such as the pickup rollers that pull the paper into the printer, and some rollers apply pressure to the printed page in order to fuse the toner. Some printers use separator pads to ensure only one piece of paper is fed into the printer at one time. Some laser printers print on both sides using the printer's existing hardware; other printers require a duplexing assembly to move the paper through the print path a second time to print on the reverse side Transfer corona assembly The HVPS applies a high-voltage charge to the charging roller or, in older laser printers, to the corona wire. The primary charger roller, or corona wire, then charges the paper so that the toner from the drum can be transferred onto the paper as it passes under the drum. After the paper passes the drum, the static charge eliminator strip drains the charges from the paper, so that it doesn't adhere to the toner cartridge and create a paper jam. The charged corona wire in a laser printer creates ozone. Ozone is a triatomic molecule that, in the lower atmosphere, is an air pollutant capable of causing respiratory illness in humans. To keep the concentrations of ozone below the currently regulated standard, many newer laser printers employ ozone filters. The ozone filter is a replaceable activated charcoal filter. You change the ozone filter after a specified number of pages have printed. The maintenance instructions for your printer specify how often you should replace the ozone filter. Some color printers use a transfer belt instead of a drum. The belt is charged and passes in front of all the colored toners, so the colors are applied in precise layers at the same time. The belt then transfers the toner to the paper Fusing assembly The fusing assembly is composed of rollers and a heating lamp. It applies heat and pressure to adhere the toner permanently to the page Electronic control package The electronic control package is also known as the printer control circuitry or the main logic assembly. This component is responsible for communicating with the internal printer memory, the control panel, and the computer that sent the print job. CTEC1465_aplus_Printers.docx Page 5 of 23

6 6.1.3 The laser printing process All laser printers use basically the same process to produce images. Through the use of negative and positive electrostatic charges, a laser writes the image to be printed into the charges, and then negatively charged toner is attracted to the positively charged paper. The following describes the steps in the laser printing process shown in Exhibit Cleaning and erasing A rubber blade clears the excess toner from the drum. Another roller or corona wire removes the charges from the drum Charging or conditioning The primary charge roller (in newer laser printers) or primary corona wire (in older laser printers) applies a negative charge of approximately -600 volts to the EP drum Writing or exposing The laser beam reduces the negative charge to about -100 volts on the EP drum in the areas that become the image to be printed Developing Areas of the drum that were written to by the laser attract toner Transferring A positive charge of about +600 volts is applied to the paper by the transfer charging roller or corona wire. The ink is transferred to the paper due to the charge Fusing Pressure and heat set the toner to the paper. A 350 F fusing roller melts the toner, and by squeezing the paper through a set of rollers, presses the toner into the paper. CTEC1465_aplus_Printers.docx Page 6 of 23

7 Note: Some sources place the cleaning and erasing stage at the beginning of the process. Others place it at the end of the process. In either case, it prepares the drum for receiving and printing the next image Impact printers Impact printers strike the paper with an inked ribbon to produce images. Impact printers include dot-matrix printers and daisy wheel printers Dot-matrix printers Dot-matrix printers have been around for as long as personal computers have been available. They are rather rare today, but they still have their place in some companies, because multipart forms can be printed on them. These printers are noisy and slow compared to other printer types. The noise comes from the impact nature of the print method. Print quality on dot-matrix printers is comparable to that produced by a typewriter. One of the main uses of typewriters was typing letters. Thus, the top print quality of a dot-matrix printer is referred to as near letter quality (NLQ). A dot-matrix printer uses a print head that usually contains 9 or 24 pins. The pins are pushed forward in patterns to form letters, numbers, and other characters. The pins strike an inked ribbon, and the ribbon strikes the paper. Nine-pin printers produce low-quality images. Some printers print over the same area after moving the paper slightly to overprint the first set of dots, thus improving the print quality. Twenty-four-pin printers have smaller pins closer together, so they produce a finer image than 9-pin printers do. The paper is pulled through the printer by a tractor feed or friction. CTEC1465_aplus_Printers.docx Page 7 of 23

8 A tractor-feed uses a sprocket to mesh with holes in the side of continuous-form paper. The sprockets turn, pulling the paper through the printer. Friction-feed uses single sheets of paper. The roller is held tight against the print head, and the paper moves through. Typewriters use friction feed. Most printers have a lever for switching between tractor feed and friction feed. The continuous-form paper usually has perforations at 11-inch or 14-inch intervals so the paper can be separated into standard-sized pages. The paper is also perforated along the side, so that the area with the tractor holes can be removed after printing. When you're setting up the paper in the printer, align the top of the page with the print head so that pages don't print across the perforations. Banners are often printed on dot-matrix printers using continuous-feed paper. Banners can be printed on perforated paper, usually without worrying about whether the paper is at the top of the first page. You might also print banners on paper that has no perforations between sheets. Multipart forms are the main use of dot-matrix printers now that other printer types have become more affordable and easier to use. The forms can be preprinted or blank. Preprinted forms require careful alignment so that the print falls inside the boxes or on the lines of the forms. Friction feed was primarily used for envelopes and single sheets of paper. Some dot matrix printers include a paper tray from which single sheets are fed, but more often, you must insert the single sheet, set the lever for friction feed, and print each page, one at a time. Dot-matrix printers usually have either a serial or parallel interface connection. These printers were the usual choice for users when personal computers were first introduced (before interfaces such as USB, infrared, and IEEE 1394 were introduced). It's also rare to find a dot-matrix printer with a built-in network interface. Some printers have both serial and parallel interfaces so that users can choose. Dot-matrix printers don't usually have a lot of optional features. However, some printers have slots for adding font cards, memory, or additional paper feeders for easy switching between single sheets and continuous-form paper Daisy wheel printers Daisy wheel printers produce letters only in the font that is on the wheel installed the printer. To change the font, you have to remove the wheel and install another wheel with the desired font. Exhibit A daisy-wheel CTEC1465_aplus_Printers.docx Page 8 of 23

9 Band printers Band printers have the letters, numbers, and symbols repeated multiple times around on a band. The band moves at a high speed and strikes the ribbon when struck by hammers. There are hammers for each column of print on the page. Some band printers combine dot-matrix pins with the hammers for each print column Thermal printers Thermal printers produce output with heat. The image can be created through one of two methods: Direct thermal printers use coated paper. A row of heating elements is used to burn dots directly onto the paper. These are monochrome printers and require a special paper that will accept the image from the heating elements. For example, thermal paper was used and is still used in some fax machines. Thermal wax transfer printers use ink in a wax base. The ink is melted from the transfer ribbon by a heating element in the print head. Separate cyan, yellow, magenta, and black transfer ribbons are used to create the image. The cooled wax becomes a permanent image on the paper. These printers don't require special paper. The thermal print process is similar to the processes for inkjet and laser printers. Paper is pulled into the printer through a feed assembly either in single sheets or from a roll of paper. The paper is then exposed to one of the processes described above, and the image is fused to the paper Other printers Explanation Most corporate and home users use either an inkjet or laser printer. A few people still use dot-matrix printers for special requirements or because they never upgraded as newer technologies became available and at lower prices. There are several other types of printers that you might encounter in your support career. Most of these are too expensive for the casual user, but as prices continue to drop on printer technologies, even these more expensive printer types might become more commonplace. Most of the printers mentioned in this topic are designed for high-quality production of graphics. They produce a higher-resolution image even if the DPI statistics listed are as the same as those of inkjet or laser printers. Printer resolution refers to addressable dots per inch. Each of these dots can be composed of over 25 dots, thereby enabling a 300 DPI image to look the same as a 4800 dpi inkjet printout. CTEC1465_aplus_Printers.docx Page 9 of 23

10 Solid-ink printers Solid-ink printers use sticks of wax that are melted to create the ink for printing. There are usually cyan, magenta, yellow, and black sticks. These are heated to a melting point. After being combined to form the various colors in the image, the ink is then sprayed onto the drum. The paper passes over the drum and under a roller, and the image is transferred onto the paper. Solid-ink printers are environmentally friendly, because they don't produce ozone as laser printers do, and the ink is nontoxic. The process doesn't use excessive heat, as laser printers do. The output from solid-ink printers is very high quality. The ink sticks last for approximately 3000 pages, compared to an average of 1500 pages for laser printers or 500 to 1000 pages for inkjet printers Dye sublimation printers Another high-quality printer is the dye sublimation printer, often referred to as a "dye sub" printer. The dye is a solid, contained on either a ribbon or a roll. The roll consists of consecutive pages of cyan, magenta, yellow, and sometimes black. The term "dye sublimation" can be a bit of a misnomer. The dye is a solid dye, so that part of the name fits fine. However, the scientific process of sublimation refers to a solid being converted to a gas without its becoming a liquid in between. Although this does happen in a few very high-end printers, most dye sub printers actually use a diffusion process. The dye diffusion thermal process is known as D2T. To transfer the dye from the ribbon or roll, the print head is pushed against the paper by weights or springs. The depth of color is regulated by varying the heat applied. This method enables printing without the use of either halftones or dithering, which are required for other printing methods. The transparent dyes are combined to create a wide variety of colors, with 256 possible shades of each color. Dye sub printers require special paper, which has a special layer to receive the dye. To protect the output from water, UV light, and fingerprints, a layer of lamination material is applied after the image has been created. Dye sub printers print square dots, with higher densities of color in the center of each dot and lower density at the edges. The density varies by the amount of power applied to the print head, thus changing the shade of the color Plotters Plotters are pen-based output devices that produce line images. (Printers produce raster images.) Plotters are typically used for precise engineering documents from CAD applications. A pen in the printer moves side to side on an X-axis as the paper moves up and down on the Y-axis. A multicolor plotter uses multiple pens to create an image. Usually, the plotter is a carousel containing 4 to 12 pens, but in some plotters, you need to change the pen to each color as you need it. CTEC1465_aplus_Printers.docx Page 10 of 23

11 Plotters create lines with the pens. Other printers can create lines only by spacing the dots very close together. Curved lines produced with a pen are smoother than those produced with dots. Most plotters are used to create engineering documents. Some other industrial uses have replaced the pens with cutting devices. For example, in the garment industry, rather than printing from the application, you cut fabric. The sign industry also uses plotters with cutting devices to cut out signs; an application outputs the sign shape to the material to be cut D Printers 3D printing or additive manufacturing is a process of making three dimensional solid objects from a digital file. The creation of a 3D printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the entire object is created. Each of these layers can be seen as a thinly sliced horizontal cross-section of the eventual object. CTEC1465_aplus_Printers.docx Page 11 of 23

12 6.2 Topic B: Printer installation Objective 4.2 Given a scenario, install, and configure printers. Use appropriate printer drivers for a given operating system Print device sharing o Wired o USB o Serial o Parallel o Ethernet Wireless o Bluetooth o Infrared (IR) o x Printer hardware print server Printer sharing o Sharing local/networked printer via Operating System settings 1.12 Install and configure various peripheral devices. Output devices o Printers Inkjet printer installation Most local printers connect via USB today, so when you connect the printer, Windows automatically detects it and attempts to install the driver for you. Your printer likely comes with a CD-ROM, containing drivers and additional software to enhance the print quality. Exhibit 6-11 shows the bubble alerting you that new hardware has been found on your computer. CTEC1465_aplus_Printers.docx Page 12 of 23

13 If Windows has the appropriate printer driver, it begins installing the driver. If Windows doesn't have or can't find the right driver, you need to install the appropriate driver software for your printer. Windows will guide you through the process. Exhibit 6-11: Identified new hardware notification in Windows 7 Exhibit 6-12: Notification that Windows 7 can't automatically install the appropriate driver Some printers come with a utility for monitoring the ink levels in the cartridges, so you know when ink supplies are getting low and need to be replaced. Exhibit 6-13 shows such a screen from such a utility. Notice that it includes information about the current print job and about the ink levels in the printer. Exhibit 6-13: A utility for monitoring ink levels CTEC1465_aplus_Printers.docx Page 13 of 23

14 Although you can purchase kits for refilling cartridges, using one usually voids the printer warranty. If you do refill a cartridge, make sure that you get the ink that's right for your printer. Thermal inkjet printers need ink that can withstand high heat. Getting a water-soluble ink for a solvent-based ink printer or vice versa can result in improper application of the ink to the page and create a major mess. Because the print head is contained in most print cartridges, a cartridge should be refilled only two or three times Printer interfaces Today, most inkjet printers are connected locally by USB interfaces, while others support wired or wireless Ethernet network connections, so that they can be connected directly to your home or business network. Exhibit 6-14 shows the communications interfaces -- an older parallel port and a newer USB port -- on an inkjet printer. Exhibit Communications interfaces on an inkjet printer (1 = Centronics parallel port, 2 = expansion port, 3 = USB type B port, 4 = power connector) In Windows, be sure to configure the printer so it uses the right connection type: If it's using parallel, be sure that you've specified the correct LPT port. The default of LPT1 is usually fine. If it's using serial, verify that you've specified the correct COM port. COM2 is preferred for printers. COM1 is generally reserved for modems. CTEC1465_aplus_Printers.docx Page 14 of 23

15 Exhibit 6-15 shows Device Manager information for a printer connected to a computer. Exhibit Port identified for the printer Installing an inkjet printer To install an inkjet printer: 1. Connect the printer to a computer, using the correct interface. 2. Plug the printer in. 3. Power it up. 4. If you're connecting the printer to a Windows computer, Windows will probably recognize that you've connected a new device and will install drivers for it. 5. If drivers aren't installed automatically, you can do it manually, using the materials that shipped with the printer. You can also obtain the latest drivers from the manufacturer's web site. If your printer is configured with an incorrect printer driver, Windows won't be able to send documents to the printer. If you send a document to the printer and it doesn't show up in the queue, check Device Manager to see if it's reporting any driver problems. If it is, you should reinstall or upgrade the driver Upgrading the device driver To upgrade a device driver, open Device Manager, right-click the printer, and choose Update Driver Software (in Windows 7 and Vista) or Update Driver (in Windows XP). Then complete the wizard to install the new driver. You can also use any installation program that comes from the printer's manufacturer. CTEC1465_aplus_Printers.docx Page 15 of 23

16 After the printer is connected and working, you can configure the options for best performance. Then print a test page to verify that the printer is working properly and that it's compatible with any programs or operating systems deployed. Also, take a few minutes to educate users about basic printing functionality Laser printer installation When a printer is shipped to a store or to you, the toner cartridge is packaged separately or otherwise secured to prevent toner from dispersing inside the printer during shipping. Therefore, the first step in installing a laser printer is to unpack the printer and the toner cartridge from their respective packaging. Laser printers usually come with chunks of Styrofoam in place of the toner cartridge. Other components might be taped down so that they don't move during shipment. Be sure to remove all of the packing materials and tape before trying to use the printer. Follow the directions to remove any packing materials and tape that might be inside the printer. Check the documentation for the toner cartridge for installation procedures. Usually, you start by gently rocking the cartridge from side to side to distribute the toner, as it's to have likely settled during shipment. According to the manufacturer's directions, remove the tape insert from the toner cartridge and install the cartridge in the printer. On some printers, the drum and some other components are outside the cartridge. If this is the case, refer to your documentation for how and where to install them Interfaces Laser printers are used in a wide variety of situations. These printers have the most widely varied connection types of any printers. Most laser printers have two or more connection interfaces. These could include: USB IEEE 1394/FireWire Parallel SCSI (older models) Serial Wired or wireless Ethernet network connections Examples of the communications interfaces on a laser printer are shown in Exhibit Exhibit 6-16: Communications interfaces on a laser printer: from left to right RJ-45 Ethernet, USB Type B, Centronics parallel. CTEC1465_aplus_Printers.docx Page 16 of 23

17 Some interfaces also include network connections, infrared ports, and wireless connections. An RJ-45 network connection enables the printer to be connected directly to the network. The printer hardware itself provides print server functionality and can be managed using the printer's onboard controls or through management software or a browser-based utility. Infrared and other wireless technologies, such as Bluetooth and IEEE x, enable users to send jobs to the printer without physically connecting the printer and computer with a cable. Again, the printer acts as a print server and can be managed locally or remotely Installing a laser printer To install a laser printer: 1. Connect the printer to the network or a computer, using the correct interface. 2. Plug the printer in. 3. Power it up. 4. If you're connecting the printer to a Windows computer, Windows will probably recognize that you've connected a new device and will install drivers for it. 5. If drivers aren't installed automatically, you can do it manually, using the materials that shipped with the printer. To upgrade a device driver: 1. In Device Manager, right-click the printer and choose Update Driver Software. 2. Complete the wizard to install the new driver. 3. Alternately, you can use any installation program that comes from the printer manufacturer. After the printer is connected and working, you can configure options for best performance. Then print a test page to verify that the printer is working property Sharing a printer on the network in Windows 7 1. Open Devices and Printers. 2. Right-click the printer you want to share, and click Properties. 3. Select the Sharing tab. 4. Check Share this printer, and add a unique name for the printer. 5. Click OK. CTEC1465_aplus_Printers.docx Page 17 of 23

18 6.2.7 Installing a network printer in Windows 7 1. Open Devices and Printers. 2. Click Add a printer. 3. Click Add a network, wireless or Bluetooth printer. Windows searches for available printers on the network. 4. Select the desired printer and click Next, or click "The printer that I want isn't listed". If the printer isn't listed, you can use the wizard to browse for it, then enter its share name, TCP/IP address, or host name. 5. If the print drivers are available on the network, Windows prompts you to install them. Click Install driver. 6. Enter a name for the printer and click Next. 7. If desired, set as the default printer and print a test page. The default printer will have a checkmark displayed on its icon. 8. Click Finish. 6.3 Topic C: Printer maintenance This topic covers the following CompTIA exam objectives for A Objective 4.3 Given a scenario, perform printer maintenance. Laser o Replacing toner, applying maintenance kit, calibration, cleaning Thermal o Replace paper, clean heating element, remove debris Impact o Replace ribbon, replace print head, replace paper Maintenance Sometimes, simple maintenance is all that's needed to keep a printer running smoothly. Check the manufacturer's documentation for each device you're supporting. The documentation lists any requirements for scheduled maintenance tasks, especially on laser printers. Also check the device's log and service history to see which maintenance tasks or repairs other technicians have performed. CTEC1465_aplus_Printers.docx Page 18 of 23

19 Common maintenance tools to have with you when performing routine maintenance include: Cleaning solutions and sprays, including isopropyl alcohol and denatured alcohol Cleaning equipment, including soft cloths, such as those shown in Exhibit 6-17, and cotton swabs Lubricants Compressed air Toner vacuums and toner rags, or extension magnet brushes Screwdrivers (to open compartments) Exhibit Cleaning cloth Safety When working with any type of printer, remember to take certain safety precautions. These include following ESD safe practices, keeping dangling jewelry, neckties, and long hair away from the printer, and handling components so as not to damage them. Also, if you're clearing a paper jam, be careful about not damaging the printer, the cartridges, or yourself. And remember, the main rule for printer maintenance: Always follow the manufacturer's recommendations. When maintenance is complete, document the steps you took in the device's service log Consumables You should always keep a sufficient supply of consumables -- paper, ink cartridges, and toner cartridges -- on hand. If you must order these supplies from another person who's in charge of ordering supplies for the company, ensure that your requests are submitted in a timely fashion and that you follow up on their status. All consumables should be kept in their original packaging; in a cool, dry location, out of direct sunlight, and in a room with low humidity. If paper is too moist because of high humidity, the toner might not adhere properly. Conversely, dry paper can create static electricity, which can cause the paper to stick together, resulting in paper jams. Toner cartridges stored out of their packaging in a humid environment can result in clumped toner. CTEC1465_aplus_Printers.docx Page 19 of 23

20 6.3.4 Inkjet printer maintenance The main thing you need to do to keep an inkjet printer working properly is to replace consumables, such as paper and ink cartridges, whenever necessary. Keeping an eye on the paper tray ensures that there's always a ready supply of paper. When an ink cartridge gets low, you usually have a visual warning -- from lights on the printer, a software utility, or just poor output. Always use recommended cartridges when replacing ink supplies. Keeping the inkjet printer's environment properly ventilated helps the printer last longer. Adequate ventilation prevents the printer from overheating. Another environmental concern is keeping dust out of the printer. Most inkjet printers have a very open design, which allows dust to gather inside. The accumulation of dust can result in the following: Stray marks on the paper, if the dust gets caught on the print cartridge Overheating of elements, if dust blocks airflow around them You can use a dry cloth to remove dust or paper dander, or if it's recommended by the manufacturer, use a vacuum cleaner designed for electronics. Clean the outside of the unit with a damp cloth or with any recommended cleaning solution Laser printers Laser printers require more maintenance than inkjet printers, and the maintenance is more involved. However, regular maintenance can prevent service calls for poor print output and paper jams. Generally, there are two times when you should perform preventive maintenance on laser printers: Scheduled maintenance - Clean, lubricate, and perform adjustments based on the manufacturer's recommended schedules. Unscheduled service calls - During service calls, check the counters, such as the one shown in Exhibit Check the manufacturer's recommendations for maintenance, and clean, lubricate, and adjust components, or replace components as needed. Exhibit The counter on a laser printer (reported by printer driver) CTEC1465_aplus_Printers.docx Page 20 of 23

21 Laser printer maintenance routines might include the following tasks: Replacing toner cartridges. Cleaning internal components. (Be sure to follow safety procedures, as well as the manufacturer's guidelines for cleaning components.) For example, clean rollers are less likely to slip and cause paper jams. Replacing components -- such as the ozone filter, fuser assembly, or transfer roller -- as recommended by the manufacturer. Often the components come in a special maintenance kit that you can get from the manufacturer. To keep a printer operating smoothly, some manufacturers recommend installing maintenance kits after a specified duration of use or a specified number of printed pages, tracked by counters. (Other printers have their counters displayed on a control panel or on an onboard monitor.) After installing the maintenance kit, you might have to reset the page count. Check the documentation. Check the printer's firmware version and the manufacturer's web site to see if there's a newer version available. Newer firmware can improve print quality and provide better interoperability with newer operating systems. Check the printer's documentation to find out how to access the firmware utility (usually through the printer's administrative software or by connecting to the printer through a web browser). Recalibrate the printer to ensure that the print is crisp and clean, especially with color laser printers that may apply colors at different steps during the print process. Follow the documentation to perform any calibration procedures. Depending on your company's financial and service contracts with the manufacturer, you might receive toner and maintenance kits automatically. Some large laser printers can contact the manufacturer directly to report page counts, which can trigger the automatic shipment of maintenance kits and replacement parts. Ask about this type of arrangement before you order any supplies. When replacing components, take some time to clean out any accumulated toner and paper dust inside the printer. Doing so prevents the debris from hindering printer operations, and it keeps a clean printing environment. CTEC1465_aplus_Printers.docx Page 21 of 23

22 Manufacturers' maintenance kits often include cleaning materials. When removing toner, don't use a regular vacuum cleaner or even an antistatic vacuum cleaner. Use only a special toner-certified vacuum, which has a filter designed to catch superfine toner particles. Be sure the printer is well ventilated and situated securely on a flat surface, and keep the printer trays full. Use only recommended supplies. Remember to follow appropriate safety precautions when working with the laser printer. After you've completed maintenance, print a few test pages to verify functionality. You don't want to leave a printer inoperable after you've completed your service routine Safety issues There are some environmental and safety issues you should be aware of with laser printers. The toner can be toxic if inhaled at high levels. Spilled toner is very messy and easily stains skin, clothing, and various plastic or other materials. You should use latex or rubber gloves, and perhaps wear a mask over your mouth and nose, when working with toner. Don't use compressed air to clear out toner. Doing so can spread the particles into the air and onto other surfaces. If you get toner on your hands or clothes, use cold water and soap to remove it. Hot water can set the toner. Printers contain high-voltage power supplies, so you need to take special care when working around them. The fusing assembly also becomes very hot, so if you're working inside the printer, you need to let it cool down a bit, so that you don't burn yourself Thermal printers As with inkjet and laser printers, there are some basic steps to keeping a thermal printer running smoothly. Clean the heating element. Make sure the printer is unplugged and the element is cooled, and then use denatured alcohol and a lint-free cloth to remove any debris. Remove any debris from inside the printer using compressed air or a lint-free cloth. Be sure to clean the rollers to ensure proper paper feed during regular use. Replace paper as directed by the manufacturer's documentation. Be sure the paper is fed through the heating element. Test the feed to ensure that the paper path is free of debris or obstructions. CTEC1465_aplus_Printers.docx Page 22 of 23

23 6.3.8 Impact printers As with the other printers covered in this unit, keeping an impact printer clean helps it last a long time. Paper bits, dust, and other debris can easily get into a printer and cause problems. You can spray compressed air into the printer to help remove such contaminants. You can use mild household cleaners on the exterior case to keep it clean. Be sure to replace the paper as necessary, feeding the paper into tractor-feed path and ensuring that the paper is evenly aligned. Replace the ink ribbon when the printed output begins to fade, and replace the print head as recommended by the manufacturer to keep the printed images sharp and to ensure that the print is clear in multipart forms. 6.4 Unit summary: Printers Topic A In this topic, you learned about inkjet printers and how they force ink through nozzles by using thermal bubble or piezoelectric technology. Next, you learned that laser printers use the electrophotographic process to produce images. You identified the components of a laser printer, and you listed the stages involved in the laser printing process. You also learned about impact printers, such as dot-matrix printers, which are slow and noisy but still good for printing multipart forms. Finally, you learned about other types of printers, including solid-ink, thermal, and dye sublimation printers, and plotters Topic B In this topic, you learned the basics of printer installation and printer sharing. Then you installed an inkjet printer, and later you connected to a shared network printer Topic C In this topic, you learned how to maintain printers. You learned the steps you should take during routine maintenance of inkjet and laser printers, including replacing consumables, removing accumulated dust and toner, replacing parts based on parts-life counters, and ensuring a wellventilated environment. CTEC1465_aplus_Printers.docx Page 23 of 23