Oce Arizona 640 GT User Manual page 72

The Table Vacuum System
[49] Closing vacuum zone 4
Vacuum Zone Control Handles
The control handles determine the state of the vacuum zones. When the handle is vertical, the
zone is open and creates a vacuum in the related area. To close a zone, turn the control handle a
quarter turn clockwise to the horizontal position.
Masking the Vacuum Table
If your media does not cover all of a vacuum zone you must mask the area around the media to
create a closed vacuum system. Use scrap media or material that is equal to or less than the
thickness of the media to mask the table. You can tell when the vacuum is sealed by the sound it
makes and also by the vacuum gauge, which must read at least 20 "Hg.
Vacuum Table Foot Pedal
The vacuum foot pedal toggles the table vacuum on or off. It helps the operator to secure the
media on the vacuum table since it allows hands-free operation. The vacuum must be turned on
prior to starting a print, and the vacuum cannot be turned off until a print is completed.
Vacuum Gauge
The vacuum gauge is located on the table. It provides a visual representation of the actual
pressure in the vacuum table system.
NOTE
Use the vacuum gauge to determine if a zone is properly masked. When the active zone is
properly masked the gauge will read at 20"Hg (68 kPa) or higher. Small leaks can reduce this
number and therefore the efficiency of the vacuum. Porous media can also degrade the vacuum
effect.
If the vacuum gauge for an active zone reads below 10"Hg (34 kPa) and you have ensured that
the area is properly masked and taped off, you may have a leak in the vacuum system. Place a
service call only if you determine that the zone is correctly masked and the gauge reads
consistently low.
How to Maintain the Vacuum Overlay Sheet
If ink build-up occurs on the overlay sheet, remove the ink. If it is not removed, the print gap can
be affected and this may affect the vacuum table's ability to secure the media properly. To
72 Chapter 5 - How to Operate Your Océ Arizona Printer
Océ Arizona 600 Series