Datalogic ENC-58 PROG, Инструкция по эксплуатации, Страница: 28 / 38

ENC58 PROG
23
We can set a resolution of 55000 PPR (
Resolution
= 55000) to
control the movement of the cable and thus of the axis with a tenth of
a millimetre resolution.
In this way we convert a rotary measurement value (55000 PPR) into
a linear measurement value, therefore we are able to control the 5.5-
m long linear travel with a tenth of a millimetre resolution.
Example 4
Let's assume that the encoder is used to control the movement of a
chain conveyor. The chain conveyor is equipped with multiple
stations and has an overall length of 14.847 m. If we set a resolution
of 14847 PPR (
Resolution
=14847) we have precise control over the
movement of the chain conveyor and
its positioning at the stations with a millimetre resolution.
Position
It is used to show the current position of the encoder.
The position value is calculated considering the preset and scaling
values that have been entered. Furthermore the counter reads the
rising and falling edges of both channels, so the position value is
shown after the x 4 pulse multiplication (x 4 resolution).
When you start the programming interface, 0 is displayed next to this
item. Press the READ button to read the current position value of the
encoder.
If the Continuous Read option is not active, the position is read at
each press of the READ button.
Otherwise if you wish a continuous reading of the position value, you
must add
a check to the Continuous Read option, then press the READ button;
the button turns red.
To deactivate the continuous reading press the READ button again.
Preset
This encoder provides the zero signal (Index pulse) once per
revolution as relative positioning reference (home position, see the
Figure on page 9).
In this way a unique position can be identified at a well-known point
in the 360° revolution of the encoder shaft. This function allows to set
the point in the revolution at which the 0 pulse will be output.
It is useful, for example, when you want the zero position of the
encoder and the zero mechanical position of the axis to match.
When you want to set the position of the 0 signal in the revolution
you must move the axis to the desired position, then press the
PRESET button while the encoder and the mechanical assembly are
in stop. In the Z Pulse Position field next to the PRESET button the
real physical position.