Technical FAQs
Technical Questions, FAQs
Questions
1) Do you offer technical support on the products you sell? Do you offer repair services for Telpar Printers?4) My serial printer prints only gibberish, random characters or the same character(s) over and over.
5) My new printer is powered up and connected to
the host, but nothing happens when I send a print job to it.
6) My new printer is
powered up and connected to the host, but it only feeds some paper and then stops when I send a print job to it.
There is no print.
7) My printer constantly jams.
8) The print on my document is too light/blurry. I can hardly read
it!
Answers
1) Do you offer technical support on the products you sell? Do you
offer repair services for Telpar Printers? Can you do custom designs?
Yes, Telpar has both technical assistance and repair services
available to all customers. Please check under Support for more information.
Telpar also has an in-house design
team which can offer custom design services
for those applications requiring functionality beyond that found in our standard product line. Please contact us for
more information regarding any of these services.
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2) What’s the difference between Impact Printers and Thermal
Printers? Which one is right for my application?
Telpar offers two basic types of printers in
its product line – Dot Matrix Impact Printers and Direct Thermal Printers. The general distinctions between these
two printer types are discussed briefly below:
A Dot Matrix Impact Printer prints inked
images on paper by electrically driving solenoid pins into an ink ribbon situated between the pint mechanism and the
paper. Because each solenoid pin is controlled individually, a dot matrix printer has the flexibility to print
various fonts and even some simple graphics on ordinary paper. If a special, multicolor ribbon is used in the
printer mechanism, impact printers may print several colors within the same document.
Advantages of
an impact printer:
- Printed ink is relatively fade resistant and long lasting when compared to thermal printer documents.
- Generally lower initial cost to purchase than thermal printers.
- Prints on ordinary paper mediums such as writing paper and photocopy paper.
Disadvantages of an impact printer:
- Noisy operation when compared to thermal printers.
- Ink ribbon has a relatively short lifetime and must be periodically replaced.
- Slow operation when compared to thermal printing.
- Low resolution print quality – questionable barcode readability.
A Direct Thermal Printer prints information by applying fine points of intense heat via a thermal
print head directly to paper treated with a heat sensitive coating known as thermal paper. The coating on the
thermal paper, which is usually found on one side of the paper only, changes color very quickly in the presence of
intense heat. Although some thermal printers have the capability to print in red or blue colors, most thermal
printer applications require a document which displays black information on a white
background.
Advantages of a thermal printer:
- Excellent print quality resolution when compared to impact printers – perfect for bar-coding and graphics purposes.
- Very fast operation when compared to impact printers.
- Quieter operation when compared to impact printers.
- No ink ribbon to replace.
Disadvantages of a thermal printer:
- Requires special thermal paper which typically costs more than the ordinary paper used in impact printers.
- The printed information fades relatively fast, especially when exposed directly to bright light and warm/hot temperatures for extended periods of time (for example, a thermal receipt stored on the dash board of a car over several weeks time will fade significantly).
- Generally more expensive to purchase than an impact printer.
Other Resources: Glossary of Terms (PDF 114 KB)
Thermal Paper Construction Guide (PDF 338 KB)
Paper Resources (PDF 136 KB)
3) A blank document or ticket is presented to me after a print job has been sent — no print can be seen.
If you are using a Thermal Printer:
First, make sure that you are using thermal paper in the printer and not an ordinary paper roll. Thermal paper has one side that is chemically treated with a heat sensitive coating. The treated side is usually shinier than the untreated side. If you scrape your fingernail over the treated surface, the scratch mark should turn light grey after several seconds.
Next, check to make sure that the thermal paper has not been loaded into the printer upside-down. The thermal coated side of the paper must make direct contact with the heating elements of the thermal print head to successfully print. If the uncoated side of the paper makes contact with the print head heating elements, then no visible printing will occur. The printer will still advance paper according to the print job that was sent, however, you will only receive a blank ticket or document.
Make sure the print darkness control on the printer is set to a reasonable level for print intensity. The print darkness control on thermal printers may be found on the printed circuit board controller (either as a dip switch setting or as a potentiometer adjustment), or it may be set through the host via a control code or escape sequence. Try not to run the printer at the full darkness setting as it will wear out the thermal print head more quickly than setting the darkness to a lower setting. Adjust the darkness control just enough so that the print is crisp and legible. Reference the user manual for your printer to determine where the Darkness Control is located and how to adjust it.
Finally, the printer itself may be defective or have a loose connection. Most thermal print heads have some type of cable or wire assembly that connects the print head to the circuit control board. Verify that this cable or wire assembly is securely connected at both ends, and make sure that there are no loose wires that have slide out of the connector housing at either end.
NOTE: To verify the proper cable connections at the control board and print head, you will most likely need to remove some portion of the printer cover or chassis. If the printer is still under warranty, or if you are not sure what to do or where to look, please call Telpar Technical Support for more help.
If you are using an Impact Printer:
Ensure that there is an ink ribbon present in the printer, and that it is seated correctly in the printing mechanism. Make sure that the ribbon has been fed between the paper and the print head mechanism. Make sure the ink ribbon is not excessively dry (out of usable ink). If in doubt, use a fresh ribbon.
Make sure the printer darkness control setting on the printer’s control circuit board has been adjusted to provide
enough energy to force the printer pins fully into the ink ribbon and paper.
Try not to run the printer at
the full darkness setting as it will wear out the ribbon more quickly than when set at a lower setting. Adjust the
darkness control just enough so that the print is crisp and legible. Reference the user manual for your
printer to determine where the Darkness Control is located and how to adjust it.
If you can not easily solve
the printer problem on your own, please call Telpar Technical Support for more help.
4) My serial printer prints only gibberish, random characters or the same character(s) over and over.
If your printer is communicating with a host (such as a computer, PLC, or another type of controller) through a serial communications port, then the serial communication settings of the printer must match the settings of the host. This is usually accomplished by physically adjusting switch settings on the printer’s main circuit board, and then cycling power to the printer so the settings can take effect. A common result of printing with mismatched communication settings between the host and a serial printer is gibberish, apparent random characters, or repeating a character(s) printed on the document.
The printer’s communication settings are typically adjusted via a DIP SWITCH located on the printer’s control board. A typical dip switch contains a group of four or eight individual ON/OFF switches (see diagram below).
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Dip switches can be seen in two places for this example – they are labeled SW1 and
SW2 on the circuit board’s silk screen. In this case, both dip switches are eight positions wide
(labeled 1 – 8 from left to right on each switch). NOTE: the “ON” direction for each switch is in the “up” direction (ON = Switch is Closed). |
By changing the switch settings, the user may change the communication attributes of the printer
to match the host settings. Examples of the printer’s communication attributes include the printer’s Baud Rate
(communication speed), the number of Data Bits sent, the number of Stop Bits sent, and Parity Checking information.
You must reference the user manual for the printer you have to determine how to set the dip switches to
match your host settings.
Several standard Telpar printers, such as the SP-327 and SP-328, do
not have dip switches and therefore, do not allow changes to the printer’s communication settings (however, DIP
SWITCH options are available for these printers). In these cases, the baud rate, data bits, stop bits and parity are
set in the firmware as a default and are automatically loaded each time the printer is powered. You must reference
the user manual to determine the settings
required for the host, which will correctly communicate to these types of printers.
If you can not
easily solve the printer problem on your own, please call Telpar Technical Support for more help.
REMEMBER: If you
make a change to the Dip Switch settings, you must cycle power before the changes can take effect!
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5) My
new printer is powered up and connected to the host, but nothing happens when I send a print job to it.
Verify that the printer is truly powered. Most printers have a power indicator light which
illuminates to indicate that the printer has power. This indicator may be found mounted to either the printer’s
chassis or on the printer’s main circuit board.
Verify that there is a cable connecting the printer to the
host, that the cable is securely connected at both ends, and that the cable is of the correct type for the printer
application (Null Modem with handshaking lines vs. Straight through, 1-to-1 cable for example). If you are using
Hardware Handshaking for data flow control, make sure the correct cable lines are being used and wired to the
correct connector pins.
Reference the user manual for your printer to determine the correct cable to use and/or the pinout of
the cable in question.
Determine if the printer has entered into error state – such as a cutter fault error
or paper jam error. Most printers have an error status light (or lights) which may illuminate or flash if the
printer senses it has a problem. These indicator(s) may be found mounted to either the printer’s chassis or on the
printer’s main circuit board. Reference the user manual for your printer to determine if the printer is in an error
state, and if so, determine what the particular error is. Typically, a printer won’t print if it is in an error
state.
If the printer has a Black Mark Detector and you are not using black marked paper, check the Dip
Switch settings on the printer control board to ensure that the black mark option is not active as this will
typically cause printer problems. Black Mark paper has a square, black mark evenly spaced along one or both edge(s)
of the paper to indicate the beginning of the next form.
REMEMBER that if you make a change
to the Dip Switch settings, you must cycle power before the changes you made can take effect!
Check all of
your printer’s Dip Switch settings to make sure that they are set correctly for your application. Some
printers, for example, have a switch setting that selects either parallel printing OR serial printing. If you are
connected to the serial port, but have the printer set for parallel operation, the printer will not print.
Reference the user manual for your printer to determine the correct settings for your application.
REMEMBER that if you make a change to the Dip Switch settings, you must cycle power before
the changes you made can take effect!
Are you trying to print through a printer driver in a Windows operating
system? If yes, did you install the appropriate driver for your printer and set it up on the correct port (LPT1,
COM1, USB001 for example).
Drivers for Telpar’s printer are available for download at our website
under Printer Drivers. If you cannot
easily solve the printer problem on your own, please call Telpar Technical Support for more help.
NOTE: Most
versions of MS Windows come with an accessory called HyperTerminal, which is useful for performing
simple, basic testing on a serial (RS-232) type printer. If you are having problems printing to a serial printer
from your application, you can try using Hyper Terminal to help you determine the actual cause of the problem
(whether it’s due to the application, the printer, the communications cable, or the host – such as a computer).
6) My new printer is powered up and connected to the host, but it only feeds some paper and then stops when I send a print job to it. There is no print.
Determine if the printer has entered into error state – such as a cutter fault error or paper jam error. Most printers have an error status light (or lights) which may illuminate or flash if the printer senses it has a problem. These indicator(s) may be found mounted to either the printer’s chassis or on the printer’s main circuit board. Reference the user manual for your printer to determine if the printer is in an error state, and if so, determine what the particular error is. Typically, a printer won’t print if it is in an error state.
If the printer has a Black Mark Detector and you are not using black marked paper, check the Dip Switch settings on the printer control board to ensure that the black mark option is not active as this will typically cause printer problems. Black Mark paper has a square, black mark evenly spaced along one or both edge(s) of the paper to indicate the beginning of the next form.
REMEMBER that if you make a change to the Dip Switch settings, you must cycle power before the changes you made can take effect!
Are you trying to print through a printer driver in a Windows operating system? If yes, did you install the appropriate driver for your printer and set it up on the correct port (LPT1, COM1, USB001 for example).
Drivers for Telpar’s printer are available for download at our website under Printer Drivers. If you cannot easily solve the printer problem on your own, please call Telpar Technical Support for more help.
NOTE: Most versions of MS Windows come with an accessory called HyperTerminal, which is useful for performing simple, basic testing on a serial (RS-232) type printer. If you are having problems printing to a serial printer from your application, you can try using Hyper Terminal to help you determine the actual cause of the problem (whether it’s due to the application, the printer, the communications cable, or the host — such as a computer).
7) My printer constantly jams.
There are five factors that play a significant role in most paper jams:
- Obstructions in the paper path.
- Misalignment of the paper path.
- Incorrect paper is being used.
- An inoperable document cutter or damaged cutter blades being used.
- Customer pulls the paper before the printer is done printing or cutting.
Obstructions in the paper path: If the paper cannot smoothly travel its designed course through the
printer system, then you will probably experience some type of jamming problem. Anything that physically impedes
smooth paper travel in a printer system is called an obstruction, and obstructions will typically result in a paper
jam.
A common obstruction issue involves printer paper making contact with an enclosure in which the
printer is housed. Printer enclosures, such as a kiosk system, provide an opening for the paper from the printer to
pass through so the customer may remove the document. If the printer and enclosure opening are not aligned
correctly, the paper may bump into or rub against the edge of the enclosure and cause a jam. Therefore, careful
consideration must be given to the printer/enclosure design to eliminate printer jams due to
obstructions.
Also, if your printer has a Document Presenter option, then you MUST allow
enough space below the presenter section so that the paper loop, which will form below the presenter, does not
contact anything.
Misalignment of the paper path: All Telpar printer
systems provide a means to hold a supply of paper within the printer. The paper support mechanism within the printer
usually consists of a removable or fixed paper spindle which connects to the printer chassis and supports a paper
roll. Telpar printer systems are designed to keep the paper path aligned with the printer/cutter mechanism’s
entryway when the printers’ built-in paper support system is properly used. Correct alignment requires that the
horizontal distance between the paper edge anywhere along its path of travel and a fixed reference
parallel to the paper edge does not change (usually small tolerances are acceptable).
Kiosk designs,
or other custom printer enclosure designs, often require a method of supporting the paper supply outside of the
printer system. In this case, the design no longer uses the printer’s internal paper support, but relies on a
support mechanism external to the printer. Many paper jamming problems associated with an external paper support
design are due to misalignment issues where the external paper support mechanism is not perfectly aligned with the
printer at the onset or eventually goes out of alignment over time. Therefore, careful consideration must be given
to the design of an external paper support mechanism to eliminate printer jams due to
misalignment.
Incorrect paper is being used: Simply put, if the paper being used in the
printer system does not match the stated paper specification for that printer, you increase the probability of paper
jams during operation. For example, paper that is slightly too thick, too wide, not wide enough, etc, may not feed
through the printer straight or smoothly. Reference the user manual for your printer to determine the correct paper specification or Telpar paper part number for your
printer.
Inoperable document cutter or damaged cutter blades: If the cutter blades do
not fully open to allow the paper to freely pass from the printer mechanism through the cutter section, then the
probablility of a paper jam is near 100% (assume you’re going to have a jam!). Usually if the cutter blades cannot
open or close all the way, the printer will report that a cutter error has occurred, or at least report that a
general error has occurred. By the time the printer reports a problem due to a cutter fault, however, a significant
paper jam may have already developed.
Some reasons for the cutter blade not fully opening or closing
during a printing process are due to a faulty sensor/switch assembly in the cutter section, a component failure on
the control board related to cutter operation, or perhaps a bur or other physical defect on the cutter blade(s)
which does not allow one blade to move freely past the other. Dull blades may also cause a problem if they can not
completely cut the paper across its entire width (or if they can not cut the paper at all!).
If after
clearing one jam, future jams frequently occur, check the cutter section for residual paper cuttings which may be
blocking the cutter pathway and clear them out of the way.
NOTE: FOR MAXIMUM SAFETY, ALWAYS
SWITCH OFF POWER TO THE PRINTER WHEN HANDLING A CUTTER MECHANISM! NEVER TRY TO PRY THE CUTTER BLADES APART
– YOU MAY DAMAGE THE CUTTER!
As always, Telpar Technical Support is available for technical advice, or the printer can be
returned to Telpar for repair (RMA
Return).
Customer pulls the paper before the printer is done printing or cutting: If the
customer is allowed to make physical contact with the document exiting the printer while printing is in process,
there is always the possibility that the customer’s interaction may be disruptive enough to cause a paper jam. This
often occurs if the customer yanks or pulls the exiting document before the printing/cutting process is complete.
Therefore, careful consideration must be given to the printer/enclosure design to prevent paper jams due to customer
interaction.
Many Telpar thermal printers offer a presenter option which is designed to prevent the customer
from having access to the document until the document has been fully printed and cut. After the printing process has
been completed, the presenter mechanism presents the document to the customer. Please contact Telpar sales for more information regarding the
presenter option.
8) The print on my document is too light/blurry. I can hardly read
it!
Make sure the print darkness control on the printer is set to a reasonable level for
print intensity. The print darkness control on thermal printers may be found on the printed circuit board controller
(either as a dip switch setting or as a potentiometer adjustment), or it may be set through the host via a control
code or escape sequence. Try not to run the printer at the full darkness setting as it will wear out the thermal
print head or ink ribbon more quickly than setting the darkness to a lower setting – adjust the darkness control
just enough so that the print is crisp and legible. Reference the user manual for your printer to determine where the Darkness Control is located and how
to adjust it.
Thermal Printer: Did the light print occur immediately after changing the
paper to a new roll? If so, the paper itself may be defective. Occasionally, during the thermal paper
manufacturing process, the thermal coating may be spread too thinly or inconsistently thus producing faded and
inconsistent printing quality. Try a known good roll of thermal paper to determine if the problem is with the paper or the printer.
Impact Printer: Try replacing the ink ribbon with a new, fresh (sealed) ink ribbon to
determine if the problem is with the printer or the ribbon.
Telpar Technical Support is always available for technical advice.
9) The rightmost (or leftmost) portion of the document does not print when it should. The information that does print is crisp and clear, but where it doesn’t print (and should) is totally blank.
First, check the margin settings and page size settings of the application you are using to send print jobs to the printer – web pages from Internet Explorer for example. Are the margins settings too small? Do the paper size settings in the application software match the size of the paper you are using in the printer?
Next, check the internal print head cable or wire assembly for secure connections at both the control board end of
the cable and the print head end of the cable.
If the print head cable connector is only partially
seated or cocked within its mating connector at either end, then some print information will never reach the print
head while some will. The result will be a partially printed document.
NOTE: To verify the
proper cable connections at the control board and print head, you will most likely need to remove some portion of
the printer cover or chassis. If the printer is still under warranty, or if you are not sure what to do or where to look, please call Telpar Technical Support for more
help.
Finally, suspect that the printer is faulty and will probably need to be returned to Telpar for repair.
10) My document has continuous fine, white (or black) lines
running vertically through the entire printout. (THERMAL PRINTER ONLY)
This is a problem with
the printer itself. Either a print head heating element (or elements) has been permanently damaged, or the control
board/print head cable has been damaged or partially disconnected. The remedy for this problem usually
requires component replacement, and the cost associated with this type of repair can be quite high (if the print
head or control board requires replacement).
If the printer is still under warranty, then the owner will not incur cost of
the repair related to this type of failure. In the case of the printer being out of warranty, some owners elect to
accept a stray line or two if it does not seriously detract from the overall purpose or readability of the printed
document (from a user point of view). This practical approach can save on costly repairs for printers that have been
used in the field for years (this problem tends to occur most frequently on older printers).