HP Designjet L25500 42 in User Manual

							3.Too little ink: The whole chart looks washed out.
Try increasing the amount of ink in your RIP software, then reprint the chart and check again.
NOTE:Backlit and some fabrics substrates usually require to be used with the “High Ink Limit” option
enabled in the RIP.
Faster printing
The obvious way to increase speed is to reduce the number of print passes, although this will tend to
reduce print quality. Bear in mind the following considerations.
●With fewer than 10 passes, you may see an increase in grain.
●With 4 or 6 passes, the printer is more sensitive to substrate advance problems.
●With 4 or 6 passes, you may need to reduce the ink quantity to improve print quality.
●If you are using the high ink level option, you must use at least 10 passes.
●As you reduce the number of passes, the best curing temperature may be more difficult to find,
and may be more sensitive to the ambient temperature and humidity.
Here are some other suggestions for increasing the speed of printing.
●Concatenating prints saves time, because one can be sent while another is being printed.
●Disable the cutter. With most substrates, this saves some time at the end of the printing process.
●Increase the cool-down curing temperatures. This also saves some time at the end of the printing
process, but may cause slight substrate deformation, depending on the substrate.
See also 
Printer states on page 69.
Color calibration
The purpose of color calibration is to produce consistent colors with the specific printheads, inks and
substrate that you are using, and in your particular environmental conditions. After color calibration, you
can expect to get identical prints from your printer on different occasions.
Color calibration can be launched from your RIP software; see your RIP documentation for details.
ENWWColor calibration 47
Handle the substrate
 
						

							In outline, the process consists of the following steps.
1.A calibration test chart is printed.
2.The HP Embedded Spectrophotometer (or, if you prefer, a different spectrophotometer) scans and
measures the test chart.
3.The RIP uses the measurements to calculate the necessary correction factors for consistent color
printing on that substrate.
Color profiles
Color calibration provides consistent colors, but consistent colors are not necessarily accurate. For
instance, if your printer prints all colors as black, its colors may be consistent but they are not accurate.
In order to print accurate colors, it is necessary to convert the color values in your files to the color values
that will produce the correct colors from your printer, your inks and your substrate. A color profile is a
description of a printer, ink and substrate combination that contains all the information needed for these
color conversions.
These color conversions are performed by your Raster Image Processor (RIP), not by the printer. For
further information on the use of color profiles, see the documentation for your application software and
for your RIP.
In addition to the color profiles used for printing, you may wish to calibrate and profile your monitor
(display device), so that the colors you see on the screen relate more closely to those that you see on
your prints.
48 Chapter 4   Handle the substrate ENWW
Handle the substrate
 
						

							5 Handle the ink system
Ink system components
Ink cartridges
The printers six ink cartridges provide magenta, light magenta, black, yellow, light cyan and cyan ink
to the printheads. Each cartridge has a capacity of 775 ml.
Ink cartridges require no maintenance or cleaning. When each ink cartridge is shaken vigorously before
installation, and inserted correctly into its slot, the ink will flow to the printheads. Because the printheads
control the amount of ink that is transferred to the page, high-quality printing results continue even when
the ink levels are getting low.
CAUTION:Avoid touching pins, leads and circuitry when handling ink cartridges because these
elements are sensitive to electrostatic discharge, which can reduce the life expectancy of the device.
Replace ink cartridges
You can highlight the  icon at any time to check the ink levels of all the ink cartridges.
The front panel warns you when cartridge ink level is low. When a cartridge is empty, the printer stops
printing and the front panel provides an explanation.
HP recommends that you replace the empty cartridge with a new HP cartridge. See Order ink
supplies on page 67 and Replace an ink cartridge on page 52.
ENWWInk system components 49Handle the ink system
 
						

							Although it is possible to use refilled or non-HP ink cartridges, either choice has several serious
disadvantages:
●There is some risk of damaging the printer. In this case the printer warranty will not be valid for any
printer repairs that are related to the cartridge, nor for any problems due to ink contamination.
●You will invalidate the warranty of all printheads of the same color used in the printer subsequently,
unless and until the whole ink system (including ink tubes) is replaced.
●Print quality may be impaired.
●The printer will be unable to estimate the ink level in the cartridge, and will report it as empty.
If you decide to use refilled or non-HP ink cartridges, you will need to follow these instructions to make
the printer use a cartridge that it believes to be empty.
1.Install the cartridge in the printer (see 
Replace an ink cartridge on page 52).
2.The front panel will complain that the cartridge is empty, and the cartridge removal process will
start. Press the Cancel key to stop this automatic process.
3.At the front panel, select the 
 icon.
4.Highlight Replace ink cartridges, but do not select it.
5.Press the Cancel key and the Up key at the same time, and hold them down for at least two seconds.
6.The front panel will display a series of warning messages. In response to each message, press
the Cancel key to cancel the process, or the Select key to confirm that you wish to continue.
When you have pressed Select in response to all warning messages, the front panel will give the usual
ink cartridge status display, but the refilled or non-HP cartridge will be shown as empty with a warning
sign.
Printheads
The printheads are connected to the ink cartridges. Each printhead has two ink cartridge connection
points and two jet nozzles, which means that each printhead accommodates two ink cartridges. For
example, the following printhead image indicates a printhead that draws and jets ink from the light
magenta and magenta cartridges.
The printheads are extremely durable and do not need to be replaced every time an ink cartridge is
replaced. They provide excellent results even when the ink cartridges contain a low level of ink.
To maintain optimum print quality, the printheads are automatically tested at regular intervals, and
automatically serviced when necessary. This takes a little time and can occasionally delay printing.
When a printhead eventually needs to be replaced, the front panel will display a message.
50 Chapter 5   Handle the ink system ENWW
Handle the ink system
 
						

							CAUTION:Avoid touching pins, leads, and circuitry when handling ink cartridges because these
elements are sensitive to electrostatic discharge. Such devices are called ESD-sensitive devices.
See 
Glossary on page 75. Electrostatic discharges are one of the main hazards to electronics
products. This type of damage can reduce the life expectancy of the device.
Printhead cleaning cartridge
The printhead cleaning cartridge cleans and maintains the printheads, and seals the printheads when
they are not in use to prevent them from drying out.
The cartridge contains a roll of cloth, which is used to clean the printheads. You are notified when 90%
of the roll has been used.
The printer will refuse to start a print job if it detects the end of the cleaning roll. You should then replace
the printhead cleaning cartridge with a new one.
Ink funnel
The ink funnel collects waste ink produced during printhead servicing. It is important that this funnel is
installed, as it prevents significant deposits of ink over various other printer parts.
From the ink funnel, the waste ink passes through a tube into the printhead cleaning container.
CAUTION: The printer can become damaged if the Ink funnel is not installed or is full.
Printhead cleaning container
The printhead cleaning container stores waste ink collected by the ink funnel..
ENWWInk system components 51
Handle the ink system
 
						

							Ink system tips
For best results, always follow these guidelines:
●Install the ink cartridges, printheads and printhead cleaning cartridge before the warranty-ends
date, which is printed on the product label and packaging.
NOTE:The ink cartridges normally expire some time after the warranty ends. Refer to the ink
cartridge information on the front panel for the expiration date.
●Follow the instructions on the front panel during installation.
●Allow the printer and the printhead cleaning cartridge to clean the printheads automatically.
●Avoid unnecessary removal of the ink cartridges and printheads.
●The ink cartridges should never be removed while the printer is printing. They should be removed
only when the printer is ready for you to replace them. The front panel guides you through the
replacement procedure (or see 
Replace an ink cartridge on page 52.
●Make sure that you comply with all applicable laws and regulations when disposing of ink system
consumables.
NOTE:Shake the ink cartridges and printheads vigorously before installing them. See Replace an ink
cartridgeon page 52 and Replace a printheadon page 56.
Work with ink system components
Replace an ink cartridge
Ink cartridges should be replaced for the following two reasons:
●The ink cartridge is very low and you want to replace it with a full cartridge for unattended printing.
You can use the remaining ink in the first cartridge at a more convenient time.
52 Chapter 5   Handle the ink system ENWW
Handle the ink system
 
						

							●The ink cartridge is empty or faulty, and you must replace it to continue printing.
CAUTION:The procedure to remove an ink cartridge must be initiated from the front panel. Do not
remove an ink cartridge until the front panel prompts you.
CAUTION:Remove an ink cartridge only if you are ready to insert another one.
WARNING!Make sure that the printer wheels are locked (the brake lever is pressed down) to prevent
the printer from moving.
Remove an ink cartridge
1.On the printers front panel, select the 
 icon, and then select Replace ink cartridges.
2.Grip the blue tab in front of the cartridge that you want to remove.
ENWW Work with ink system components 53
Handle the ink system
 
						

							3.Pull the blue tab down and then pull it outwards, towards you.
4.The cartridge comes out, in its drawer.
5.Lift the cartridge out of its drawer.
NOTE:Avoid touching the end of the cartridge that is inserted into the printer, because the
connection might be coated with ink.
NOTE:If necessary, store a partially-used ink cartridge in the same position as if it were inserted
in the printer. Avoid using a partially-used cartridge that has been stored on its end.
54 Chapter 5   Handle the ink system ENWW
Handle the ink system
 
						

							6.The front-panel display identifies the missing ink cartridge.
Insert an ink cartridge
1.Pick up the new ink cartridge and find the label that identifies the ink color. Hold the ink cartridge
so that you can see the label at the top of the side that is facing you.
2.Check that the colored label above the empty slot in the printer matches the color of the label on
the cartridge.
3.Shake the cartridge vigorously for about 15 seconds.
4.Insert the ink cartridge into the cartridge drawer.
ENWW Work with ink system components 55
Handle the ink system
 
						

							5.Slide the drawer and cartridge into the slot until they lock into position.
If you have difficulty, see the Maintenance and troubleshooting guide.
6.The front-panel display confirms that all cartridges have been correctly inserted.
Replace a printhead
Printhead replacement must be performed after the printer has been turned on with the hard power
switch at the back of the printer.
WARNING!Make sure that the printer wheels are locked (the brake lever is pressed down) to prevent
the printer from moving.
WARNING!Make sure the printer has cooled down before removing a printhead. The printer will beep
if it is still hot.
56 Chapter 5   Handle the ink system ENWW
Handle the ink system