Messtechnik Sachs Irinos IR, User Manual

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Irinos IR Users Manual © 2015 - 2016 Messtechnik Sachs GmbH, Germany
Application notes
Below or above the threshold values, a reliable interpolation is not
possible. An integrated signal examination detects such errors. The
error status can be read by software in parallel to the measurement.
In case of an error, the counter channel should be reset. The
referencing procedure should be redone.
Signal quality
The signal quality depends on various factors. Important ones are:
o
Speed of the incremental encoder
The higher the speed of the incremental encoder, the smaller the
actual differential voltage. Some incremental encoders have a very
good signal quality while standing still or at low speed. As soon as
they are moved / turned, the signal quality decreases rapidly.
o
Mechanical stability of the incremental encoder and the mechanics
An incremental encoder or a measurement device, which does not
move smoothly, leads to variations in the measurement signal.
o
Adjustment of the incremental encoder
Some incremental encoders (e.g. glass scales) need to be
adjusted. An improper adjustment can lead to an insufficient
sensor signal (especially for dynamic movements).
o
Cable length and cable quality
The longer the cable, the worse the signal quality.
The more connectors are used, the worse the signal quality.
A cable with insufficient shielding or wrong line impedance
deteriorates the signal quality.
Often the reason for a signal problem is a combination of these
factors.
Suggestions
o
Please observe the cut-off frequency of the incremental encoder.
It can be found in the encoder datasheet.