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Installation manual
CNC 8055
CNC 8055i
7.
CONCEPTS
SOFT: V02.2X
Feedback systems
7.4.1 Counting speed limitation
Sinusoidal signals
The maximum counting speed (frequency) for sinusoidal feedback is 50 kHz at the 8055 and 250
kHz at the 8055i.
The maximum feedrate for each axis on linear systems will depend upon the selected resolution
and the signal pitch (distance per pulse) in use, whereas on rotary encoders it will depend on the
number of pulses per revolution.
Example 1
When using a Fagor linear encoder, the signal pitch is 20 µm. Therefore, with a counting resolution
of 1 µm, the maximum feedrate will be:
When using Fagor linear encoders, the maximum feedrate is limited by their own characteristics to
60 m/min.
Example 2
Using an indexer with a sinusoidal Fagor encoder of 3600 lines per turn, for a feedback resolution
of 1 µm, the maximum axis feedrate will be:
Since Fagor sine-wave encoders admit a frequency of up to 200 KHz, the maximum feedrate for
the 8055i will be:
(360 degrees/turn / 3600 pulses/turn) x 200,000 pulses/s. =
= 20,000 degrees/sec.= 1,200,000 degrees/min.
Squarewave signals
The maximum frequency (speed) for squarewave differential feedback is 400 KHz. with a separation
of 450 ns between A and B flanks. Which is equivalent to 90º ±20º.
The maximum feedrate for each axis will depend upon the selected resolution and the signal pitch
(distance per pulse) in use.
When using Fagor linear encoders, the maximum feedrate is limited by their own characteristics to
60 m/min.
When using FAGOR rotary encoders, their intrinsic output frequency limit is (200Kz).
8055 20 µm/pulse x 50,000 pulses/s. = 60 m/min.
8055i 20 µm/pulse x 250,000 pulses/s. = 300 m/min.
8055 (360 degrees/turn / 3600 pulses/turn) x 50,000 pulses/s. = 5,000 degrees/sec.= 300,000
degrees/min.
8055i (360 degrees/turn / 3600 pulses/turn) x 250,000 pulses/s. = 25,000 degrees/sec.= 1,500,000
degrees/min.
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