Updated: Nov 20, 2018
Critical Definitions ( Longer list Below)
Controller- The electronic assembly that sends commands to and receives commands from other devices.
Control Panel- The display and switch panel on a printer that indicates the status of the control subsystem and may be used to reconfigure the machine settings.
DC power supply- (direct current) This supply converts AC power into direct current at the appropriate voltage level to power electronic devices. These currents are commonly +5V, -5V, +24V.
Dpi- (dots per inch) A measure of resolution of print imagery. An image on a page is made of tiny dots where along a given vertical or horizontal line there are 1200 dots per inch.
Engine- The engine provides all the mechanical and electromagnetic functions to allow a signal sent from the logic board to the engine, which are transferred to independent dots on the paper.
Exit roller- (delivery roller) The exit roller is part of the fuser or delivery assembly of the printer which helps to drive paper to the output tray.
Functional subsystems- Groups of modules that handle the main functions of a laser printer. Laser printer problems can be attributed to a subsystem failure. The four primary subsystems of laser printers are as follows:
Paper handling- The mechanisms of the printer dedicated to moving paper into the machine, through the printing process without skewing, wrinkling or jamming, and out the exit. This subsystem includes the input cassette, pickup assembly, registration assembly, fuser, and –in some machines- delivery assembly.
Image formation- The modules that transfer and convert the data from the host computer into a toner image on the page. This subsystem includes the logic board, DC controller, laser, scanner, cartridge, transfer corona wire or transfer roller, and fuser.
Power- The modules of the printer that provide electrical power to the other subsystems. These include the AC-, DC-, and high voltage power supplies.
Control- The control subsystem ensures that each of the other subsystems receives the appropriate input needed, at the precise moment required. If an input fails to arrive within the precise time, the control system issues an error message, waits for the input, and/or stops the machine. The control system includes the DC controller, solenoids, photo interrupters (paper sensors) thermistor, fiber-optic cable or sensor, error display, and other control devices.
Fuser- The most common failed assembly in most laser engines or copiers is the fuser. The fuser melts toner onto the paper. In early printers it includes upper and lower rollers, a heating element, temperature sensing circuitry, a paper sensor, and an exit assembly. In later machines, instead of using a halogen lamp, heat is provided by a fixing film assembly using a heating element to fuser the image onto the page.
High Voltage Power Supply-Generates three levels of very high voltages for use by the image formation subsystem. Early printers with coronas generate –6,000 V for the primary corona wire inside the toner cartridge, +6,000 V for the transfer corona wire, and –600 V for the developer cylinder bias, also inside the cartridge. Later printers need only produce about –1,000 V, +1,000 V, and –600 V since they use more efficient charge roller technology.
Interface Board (PCA)-The electronic circuit board translates computer code from the host into a form that can be printed by the engine.
Motherboard- It is also called an I/O board, interface PCB, formatter board, or logic board. It contains computer memory, at least one microprocessor chip, the printer language interpreter, and all of the logic needed to specially instruct the DC controller in the nature of the image to be printed. Interprets simple ASCII coded instructions from the host computer and forms a dot-by-dot image of the page to be printed.
PCB-(printer controller board)-A circuit board made from the insulating laminate coated with conductive traces and pads making up the electronic circuit into or on which components or integrated circuit elements are mounted.
PCL-(printer control language)-HP’s proprietary programming language offered with Hewlett-Packard LaserJet Printers. In the early HP’s, while the graphics capabilities of PCL are somewhat limited, it requires much less data processing for the printer interface to format text for printing. Consequently, PCL-outfitted printers typically print faster and are less expensive than PostScript printers. Recent versions of PCL, PCL5, and 6, offer most of the same graphics and text features of PostScript for the PC world.
Pickup Assembly-The device which lifts one page of paper from the cassette or tray and moves it to registration in the early stage of paper handling. The assembly includes at least one pickup roller and might also include a method of separating the top page from the rest of the stock.
Pickup Roller-The rubber roller or rollers are designed to pick up a sheet of paper. When rollers become sufficiently coated with foreign matter or polished by wear, customers will likely complain about frequent paper jams.
Power Supply-The module which outputs power required for printer operations. Printers contain three power modules (or those functions within one or more circuits): AC, DC, and high voltages power supplies.
Registration Assembly- The device responsible for ensuring that the paper enters the image formation process at the proper time. Registration is accurate when the top margin of the image is correct.
Scanner-The scanner module sweeps a stream of lasers on and off onto the OPC drum, one line at a time. Each stream or “raster” results from one facet of a spinning, multisided mirror mounted on a high precision motor, passed through several other mirrors and lenses.
Other Helpful Resources
Full List Printer Definitions
10/100- Used to describe the speed of the network or interface speed capable of sending or receiving data at either 10 megabits or 100 megabits
10bt Pronounced "10 base T". The RJ-45 connector used on an Ethernet network: capable of transmitting data at megabits per second
A4 (European paper sizes A,B)European (Japanese, etc.) use letter designations (in millimeters) for specific paper sizes. These are different than the US designations (Letter, Legal, Ledger).
ADF Automatic Document Feeder
ADF assembly Automatic document feeder assembly used on MFP or AIO printers to feed documents into the printer to be scanned or copied on the flatbed scanner portion of the printer.
ADF Unit Automatic Document feeder.Part of MFP or AIO printers which feeds the paper into the scanner or flatbed for copying or scanning documents.
Aftermarket The sale of service and supplies to customers on an ongoing basis.
AIO All-in-one is a type of printer that has many features built in, such as a fax modem, an automatic document feeder and a flatbed scanner for scanning and copying documents.
Ambient Noise- Electromagnetic Interference (EMI)Is an unwanted signal that is induced into the cable from an external source (electrical cable, device, or nearby cable). Can cause packet loss, lost connections, and network slowdowns.
Analog -Refers to the process of producing a copy by means of reflecting light off of the original and onto a photo conductive material or drum. Analog machines are characterized by a lack by a lack of features and poorer image quality than a digital device.
Basis weight Weight in pounds of 500 sheets cut to a given standard size for the paper type.
Bins Older -style analog printers used multiple bins or exit trays to collate (or separate) the output.
Blackout Extended -zero voltage conditions caused by lightning, generator failure, and ground faults
Bond- Refers to standard type of printing paper.
Booklet -The process of imposing or arranging the pages on duplexed (double-sided) documents so they appear in the correct order when folded in half.
Bridge unit Some add on finishers require a bridge unit to connect the printer to the paper handling unit.
Brightness- Reflectance or brilliance of paper
Brownout -Long term under voltage caused when peak demand exceeds generating capacity.
Business color -A general class of color printing that is characterized by lower requirements around color accuracy. Business color usually refers to things like PowerPoint presentations. Most any situations where spot color is being used and doesn't have to exactly match a specific printer or Pantone color( or the need for halftone reproduction).
Bypass tray -An input paper source on a printer,fax or copier that is generally used for feeding specialty paper into the machine. The bypass tray is usually characterized by lower volumes, occasional use or the ability to feed heavier stocks.
Caliper -Thickness of a sheet paper
Card reader -Usually a credit card style reading device for controlling access to a printer or copier
Cassette -The holding area for the paper in a printer, usually with 100, 250 or 500 sheet capacities.
Clamping -Action Turn-On Threshold voltage at which the suppression device starts to conduct or turn on. Protection starts at this level; however true protection is specified by the maximum clamping voltage.
Clamping -Voltage The peak voltage appearing across the device when measured at conditions of specified pulse current amplitude and specified waveform.
Clicks -Pages produced on a printer, 5,000 clicks per month means 5,000 pages per month.
CMYK -Cyan, Magenta, Yellow and Black; the process of generating a color image by absorbing light and reflecting whats left. This is a complimentary process to RGB color generation. CMYK is the process for all commercial printing. CMYK images are characterized as less vibrant than RGB (smaller color gamut)
COF -Coefficient of friction Force needed to start a sheet feeding, as well as drag a sheet across the one underneath it as it continues to feed.
Cold- Reset Performing this will reset the printer's settings back to the factory defaults including EIO options.Will also unlock control panel menus that were previously locked. Will not reset the items in the service menu. Remove the EIO card to prevent those settings from being erased.
Collate -The separation of the printed documents for easy identification Color calibration -The setting or correcting of the image quality (color correctness) to a known standard set in the printer.
Color separation- The process of separating an electronic or hard copy image into the 4 base color components (CMYK) in preparation for printing on a color press Control Panel -Provides information on the display also via the keypad, access to settings,information and features of the printer.
Coverage- Used to describe how much toner is on a piece of print media. A standard business document is generally thought to contain between 8 and 14% coverage.
CPP -Cost Per Page; refers to a type of sale where the equipment, service and finance charges are rolled into a single, per impression (click) charge. CPP deals are generally sold with a minimum number of copies referred to as the base.
Creative Color -Creative color refers to the upper end requirements for color printing and copying. Creative color generally refers to customers with needs such as matching specific colors (Pantone), matching previously printed output, etc. Also know as Graphic color.
Crosstalk -Bleeds the signals from one pair to another pair. Causes slow transfer and blocks the transfer of data signals within the cable.
Curl -When a sheet takes on a curved quality, losing its "flatness."
DADF -Duplexing or Recirculating Document Feeder. An automatic document feeder capable of reading both sides of an original in a single pass.
Data Stream -A general term that refers to the electronic signal going to a printer. The data stream carries the PDL or page description language information.
DC Controller -Responsible for the timing,regulating the power to all fans,motors,sensors,engine test feature,tracking supplies usage and reporting all information back to the formatter
Densitometer- A device used to measure the color shade and density from a printer image. Used in conjunction with a printed test target and calibration software to set a color machine to a known value.
Desktop A printer or fax that does not require a stand of its own. Its capable of sitting directly on a counter or desktop.
Dimensional stability Change in sheet dimensions due to absorption and evaporation of moisture.
DIMM -Dual in-line memory module,flash dimms are used for permanent storage(firmware,forms,fonts,etc.).Memory dimms are for temporary storage. Document feeder- The generic term for an automatic document feeder; a way of feeding a stack of paper into a printer or scanner unattended.
Domain - A domain can be either a single server or multiple servers acting as one on a single network
Domain controller -The central computer in the domain that is responsible for authenticating or verifying a user's logon name and password.
Dot matrix printer A printer that creates characters and graphics by means of a small row of wires on its print head. The wires move forward and strike the paper through and inked ribbon, creating small dots on the page that make up the image. Dot matrix printer are characterized by low print quality and slower print speeds than laser printers
DPI- This refers to the resolution of the printer or dots per inch. Its a measure of how many dots or pixels per square inch are used to process and print the image. Generally the higher the number the better the print quality.
Drawer- The holding area for paper in the printer which usually refers to a larger capacity paper input device
Drive assemblies- Sections within the printer that help to move the paper through the printer or drive the print cartridge(s). Some drive assemblies might have motors attached to them others might be just mechanical units within the printer. driver In computers, a printer driver or a print processor is a piece of software that converts the data to be printed to the form specific to a printer.
Duplex- Information printed on both sides of the document Usually refers to output or printing, but can also be used to describe the original documents. Duplexed documents can be long edge (opens like a book) or short edge (opens like a clip board)
Duplexer- Device usually an option that can be installed in a printer to enable printing on both sides( duplex) of the media.
Duty cycle A term that refers to the amount of work that can be expected from a particular device. Duty cycle is frequently an arbitrary number and may be hard to compare from one manufacturer to another. Service technicians can be resources for determining real-world duty cycle numbers based on actual experience. Usually calculated on a monthly basis.
EDM- Electronic Document Management; the process of storing and retrieving documents, both scanned images and electronic files in a centrally controlled and secured location.
EIO- EIO (Enhanced Input/Output) is a modular interface developed by HP for its printers to expand their capabilities
Electronic Transfer Belt- ETB uses primary transfer rollers to transfer the image from each image drum to the ETB.
Electrostatic transfer belt ETB uses primary transfer rollers to transfer the image from each image drum to the ETB.
EMI/RFI (Electro magnetic interference / Radio frequency interference) Inductive or radio frequency electrical noise commonly occurring which can create erratic behavior in electronic circuits.
EMI/RFI Noise Rejection Most suppressors are poor filters of EMI/RFI noise. This is because if any filtering is added it is just a capacitor and then usually an inexpensive and ineffective one with high ESR value ( Internal impedance at RFI levels or poor dv/dt response).
Engine- An "engine" (short for print-engine) is the portion of the printer that is responsible for the actual printing of the documents.
Engine Control Unit- (ECU)regulates power distribution,laser scanner system,paper movement/monitoring,controls all clutches, motors, fans and engine test feature.
Enterprise- Generally the term enterprise refers to larger, more spread out networks.
Companies that look at " Enterprise " solutions are looking at larger, more costly; usually to cover multiple servers and a large number of end users.
Envelope feeder An attachment that generally inserts into the tray 1 or MP tray and is used for the purpose of feeding envelopes only.
Error Code Alpha or numeric code displayed on the control panel to alert the user of the condition/operating status of the printer. Some are critical and others are not.
ETB- ETB uses primary transfer rollers to transfer the image from each image drum to the ETB.
Ethernet -A type of physical network connection. Ethernet uses a specific kind of wire, connector and way of communicating on the network.
Exchange email- An email server that utilizes Microsoft Exchange rather than SMTP or Lotus Notes. Customers who use Exchange email have to use email devices that are capable of working with it.
Failure Mode- The status of protected equipment in the unlikely event of a surge suppressor failure ( due to surges of over-voltages beyond the suppressor's rated capability). Equipment can either be left operating but unprotected, or be removed from service ( the suppressor will intentionally cause loss of power or signal by tripping/clearing a system breaker/fuse).
Fax- Short for facsimile (a copy). A facsimile machine sends a digitized copy of a document through a phone line to another fax machine or MFP printer with fax capabilities
Feed assembly- An assembly in the printer that pickups up and feeds the media from the tray being used. A whole unit that can be replaced.
Feed roller -Roller that helps to feed the print media into the printer.
Feeder- Part of the printer that is used for picking up/feeding paper into the printer.
Finisher- An add-on accessory for a printer that provides the finishing options; stapling, collating, sorting, folding, hole punching, etc.
Finishing- The term used to describe how you want your printer output to be physically handled; stapled, collated, sorted, folded, etc.
Firmware- The operating software of the printer. On some printers the firmware can be updated by flashing the newer version to the printer. It might be stored on a memory dimm, compact flash card or stored right on the formatter.
Flatbed Scanning Assembly- The copy or scanning portion of mutlifunction or all-in-one printers. Used for copying or scanning documents to be either printer or emailed.
FOLD TOP CORNER / DOG EAR FOLD Printout has fold top corner left or right.
Formation Uniformity of the sheet of paper
Formatter- The part used in a laser printer that is responsible for all input/output functions. The board processes the print job from the PC or network. Commands the DC controller
FTP ( file transfer protocol)A protocol or set of instructions for how a file is transferred on a network. If two different computers or pieces of hardware both support FTP, they can share files back and forth.
Fuser- The part of the printer that bonds toner to the print media using heat and pressure
Gamut- The color Gamut is a measure of the maximum number of colors reproducible by any given technology. The color gamut for an RGB image displayed on a color monitor will be larger than one printed on a CMYK printer or press.
Giga (G)1,000 million or billion. 1G = 1,000M = 1,000,000,000.
Gigabit Ethernet- The same RJ-45 connector used for 10BT, but on a network capable of transmitting data at 1,000 megabits or 1 gigabit.
Glitch- A transient over-voltage.
Graphic color Graphic color refers to the upper-end requirements for color printing and copying. Graphic color generally refers to customers with needs such as matching specific colors (Pantone), matching previously printer output, etc. Also know as Creative color.
GUI- Graphical User Interface. The interface to a computer program. Windows is a graphical interface while DOS was a text based interface.
Hard drive Some printers have hard drives in them, multi-function printers in particular. They are use for the storage of data for spooling (or copying) print jobs from the host system very quickly and storing them until the printer is ready to print them. Can also be used for storing fonts or forms to be retrieved when needed.
Hardware- The physical pieces of a computer or network device or printer such as the hard drive, formatter, main board, etc.
High Volt Power Supply- Provides power for the charging of the cartridge and transferring of toner within the printer.
High volume- A general term that refers to printers that scan handle large amounts of paper reliably.
I/O Ports- Input/Output options for interfacing between the host(computer) and the printing device.
Image Defect- Problem with the finished printout. Can be caused by, toner cartridge(s),transfer units(rollers),fuser,laser scanner,power supply or debris in the printer
Imaging- A general term that refers to either putting marks on a page (printing or copying) or scanning (digitizing) a document
Imposition- The process of rearranging pages in a" booklet" order. If you were to fold a single piece of paper in half, page 1 and 4 are on side A while pages 2 and 3 are on side B.
Inkjet printer- A type of printing that utilizes a print head capable of squirting tiny bubbles of ink to create dots on the page. The dots, similar to a dot matrix printer, form characters and images.
Intermediate transfer belt- ITB transfer the image directly to the media
ITB- An ITB transfer the image directly to the media
ITB- Belt Intermediate transfer belt,used in color printers.The image is built on the belt and then transferred to the print media via a secondary transfer process
Jog(jogger)- The process of offset (physically shifting ) stacking a printed or copied set in order to separate it from other sets.
Joule Rating- Peak energy rating at 10/1000us wave shape applied (along with rated rms. voltage) without causing device failure. The higher the joule rating the longer the expected life of the device. In some devices joule rating will affect clamping voltage performance.
Kerberos- The Kerberos version 5 authentication protocol provides a mechanism for authentication — and mutual authentication — between a client and a server, or between one server and another server.
L-G Line to Ground L-L Line to Line L-N Line to Neutral
Laser printer- A type of printer that utilizes a laser beam to actually draw the printed image onto photoconductive material. The material then comes in contact with toner which will adhere to the image written on by the laser. The image is the transferred to the print media and fused to the page using heat and pressure.
Laser Scanner- The part of the printer that writes/charges the image on the drum to begin building the image.
LCT- Large Capacity Tray. An add-on accessory for a printer that allows fro larger amounts of paper to be loaded. Usually in the range of 1,000 to 3,000 sheet capacities. Some printers might require an additional output device to handle the added volume of paper.
LDAP- Light Directory Access Protocol. A way of maintaining address book information for email addresses in a central server and then pulling that information into a printer or MFP device.
Ledger- US paper size 11x17 inches.
Legal- US paper size 8 1/2 X 14 inches.
Letter- US paper size 8 1/2 X 11 inches.
Line printer-A general data processing term that refers to a large, high speed printer for producing output on pin fed or continuous feed paper.
LIU- Line Interface Unit, ( fax card) used in AIO and MFP printers to enable fax capabilities. Can be a separate card or embedded on the formatter.
Low Volt Power Supply- Provides all DC power in the printer to motors,fans,formatter, sensors,fuser and DC controller
Mailbox A- virtual location for storing print jobs, usually on the hard drive of the formatter. The term can also be used to indicate a physical set of output storage bins or trays.
MEAP- Multi-functional Embedded Application Platform. A Canon technology used for running programs on the copier controller
MFP- Multi Function Printer, usually capable of printing,scanning,copying,and faxing. Modes of Protection Common mode means lines compared to ground. Normal (Differential) mode means across the lines.
MPS- Managed print services
Multi-PDL- A print controller (RIP) capable of interpreting more than one PDL (page description language). Most copier multi-PDLs will work with PCL and Postscript.
Multipurpose Tray MP or Tray 1- usually a fold or drop down tray on the front of the printer used for manually feeding envelopes,thick stock and transparencies.
N-G Neutral to Ground.
Network- A group of 2 or more computers connected by a network cable for the purpose of sharing files, programs or devices.
Network drop- Refers to a physical line needed to connect a printer to the network, an RJ45 connection.
Network Interface- Communication option enabling a printer to connect in different operating environments through various different high speed options.
NIB- Network Interface Board used to connect the printer to the network
NIC- Network Interface Card. Used to connect the printer to the network via the actual data cable.
Noise- Various high frequency impulses ranging from a few mill-volts to several volts in amplitude.
Noise (electromagnetic interference or EMI)- Unwanted signals (electrical signals other than the power line voltage) that negatively affect the circuits of sensitive electronic equipment in which they occur. Effects power, phone and data lines,and can cause operation errors, data corruption and terminal lock-ups.
NVRAM- Non-Volatile Random Access Memory, a type of memory that retains its contents when power is turned off.
NVRAM- (non-volatile random access memory)Storage area on the formatter or flash device which stores information about the printer. The serial number,usage information,page counts and EIO settings. All settings in the service menu will be reset. If performed remove the EIO options and print a configuration/usage page(s). Opacity- A sheet's show-through properties
OPC- Organic photo conductor,the toner/image is formed on this type of material, drum or a belt.
Operating Line Voltage- DC voltage or rms voltage normally expected to be applied to a device.
Output assembly- Usually located just beyond the fuser,moves the media to the output section. Also known as a delivery assembly on certain models
Pantone color Industry wide standard for color matching.
Paper Deck- An accessory that can be added to a printer to enable larger volumes of paper to be loaded usually between 1000 to 3000 sheets of additional paper. Some printers might require some additional device to handle the added output.
Paper delivery assembly- This unit or section of gears and rollers helps to deliver the print media out of the printer. Usually for face down printing, but some printers might have the capabilities to have the output come out face up.
Paper Input Unit (PIU)- An assembly in the printer for feeding paper from the tray(s).
Paper Jam A page has gotten stuck in the printer or has been fed in when it was not called for or was supposed to be fed in but was not.
Paper Output Assembly (POA) - An assembly that feeds the paper out of the printer. Usually located after the fuser unit.
Paper pick and feed rollers- Roller(s) in the printer that pick up and feed the media into the printer from the cassette or other input trays.
Paper pick-up roller- Roller used to pick the print media up from the tray or other input options
Paper pickup assembly- An assembly in the printer that picks the paper from the tray or trays. The unit will have gears and possibly solenoids and electromagnetic clutches for controlling the paper pickup process.
Paper pickup roller- Roller used to pick paper from the input tray being used. Paper Tray- Used for holding the paper supply,usually capable of holding 250 or 500 sheets of standard paper.
Parallel- A type of printer cable and connection used for connecting PC's to printers Parallel Port Interfacing option bi-directional communication port .Centronics style (larger connector) interface on older printers.
PCL Printer Control Language. Developed by Hewlett Packard for Windows printing, PCL has traditionally been thought of as a lower end printing solution used primarily for office documents. Today, the gap between PCL and Postscript is nearly non-existent.
Pick-up roller- The roller that picks up the paper to begin the feeding process.
Pickup roller The roller that picks the media out of the tray to begin the feeding process.
Platen The glass on the top of a copier where a document is placed for copying.