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User Manual
Appendix 1:Installations & Setting Up
For example:
Consider printing “Sell By 19 Nov 00” in 7 High Full using a Midi printhead and the 7 GEN STD raster
onto a print area 38 mm long.
From the table above, the width of each character is 6 rasters. The message is 17 characters long
including spaces. Therefore, the required raster pitch is given by:
This will be the maximum pitch possible; any larger and the message will not fit in the print target area.
At this stage it is also worth considering if any other pitches will be required for other products to run
on the line.
The following table shows the ideal pitch for each printhead and raster combination:
For our example, it can be seen that the required raster pitch (0.373 mm) is slightly small than the ideal
pitch for the Midi 7 GEN STD (0.4 mm). This will fit the print area and may increase the potential
maximum line speed, but there will be a small gap between the drops on most substrates.
Step 2:Select the Encoder, Gearing, and Pitch Factor
A particular combination of encoder and encoder drive (gearing or wheel) will give a particular encoder
pitch; that is, the distance the product will travel for each cycle of the encoder output signal. The encoder
pitch will be multiplied by the pitch factor (a whole number) to give the actual raster pitch. This should
be as close as possible to the required raster pitch.
The table below gives the encoder pitches for standard EC-JET encoders and wheels. The encoder
pitch for other gearing or drives can be calculated using:
Where:
Wheel Circumference = Distance the product moves for one revolution of the encoder. This may be 3.
14 x roller diameter, or 3.14 x star-wheel diameter, etc., depending on the application.
The encoder pitch will be multiplied by a whole number to give the actual raster pitch. By selecting a
suitable encoder and gearing, the actual raster pitch can be made close to the required raster pitch.
Actual Raster Pitch (mm) = Encoder Pitch (mm) x Pitch Factor
PRINTHEAD TYPE
/ IDEAL PITCH (mm)
Raster
7 GEN STD
7 MIN STD
7 HI SPEED
12 GEN STD
12 HI SPEED
16 GEN STD
16 HI SPEED
16 S HI SPEED
24 GEN STD
32 GEN STD
34 GEN STD
Midi
0.4
0.4
0.5
0.4
0.7
0.4
0.4
0.7
0.4
0.4
0.4
EJ113
Wheel Circumference /
Shafter Encoder Pitch (mm)
Encoder p.p.r.
2500
5000
Application
0.200
0.100
500mm
333mm
200mm
0.133
0.066
0.080
0.040
EJ114
Required raster pitch (mm)
38mm
17 Character x 6 Raster
0.373mm
=
=
=
Encoder Pitch (mm)
Wheel Circumference (mm)
Encoder Pulses Per Revolution
