Managing Consumables
Advanced Topics 6-7
Advanced Topics
Note The factory yield estimates for consumables are determined under operating
conditions which are intended to model a large sample of customer installations. However, it is
impossible to model every operating environment, and as result some installations may
experience lower consumable yields than expected. Keep a log of actual consumable usage for
each printer. This provides the most accurate data to plan consumable purchases.
Toner
Toner yields are primarily driven by the quantity of toner applied to each page. Large black
areas, graphic images, gray backgrounds and forms outlines use more toner. If you print
mostly or only a small amount of text, you will probably reach or exceed the estimated yield.
Toner yield estimates are based on 4% toner coverage. This is a standard value used by the
printer industry, which is based on the assumption that the "typical" A4 or letter-size business
letter is 4% covered by black area.
The D640 offers a number of features that, with some trade-offs, can extend toner yield.
Density
The density value is factory set to 10, approximately in the middle of its range. The density
value can be set as low as 1 to reduce toner consumption. To the naked eye, solid area patterns
will not appear any lighter under lower settings. Reducing the density will have the largest
visual effect on gray scale patterns or the small text characters.
Experiment to see if a lower density value can satisfy your print quality requirements. Actual
toner savings will vary based on the types of images printed. The density setting can be found
under the Maintenance Menu, described in “Density” on page 2-25.
Economode
Most printers simply print a lighter pattern when an economode setting is used. However, the
D640 does not lighten the entire image. Instead, dots are turned off in strategic areas to reduce
toner use while maintaining readability. When printing text in economode, the character
outline is perfectly formed, while the inside uses fewer dots. The effects are nearly invisible to
the naked eye at a 10 point character size, but may be more readily seen on large characters.
Experiment to see if economode can be used for some, if not all of your printing. Large text-
only reports may be able to use economode with no perceptible reduction in print quality.
Economode can reduce toner consumption as much as 50%, depending on the printing pattern.
The Economode setting can be found under the Configuration Menu, described in
“Economode” on page 2-17.
