Installation manual
CNC 8035
CONCEPTS
feedback system
5.
(SOFT M: V15.3X)
(S
OFT T: V16.3X)
·201·
Example 5:
Resolution in "inches" with squarewave encoder
Calculate the necessary squarewave encoder line count and parameter settings to obtain a 0.0001
inch counting resolution on a 4 pitch ballscrew (4 turns/inch = 0.25 inch/rev.).
Since the CNC applies a x4 multiplying factor to squarewave signals, we would require an encoder
that provides the following number of pulses (lines) per turn.
Nr of pulses = ballscrew pitch / (multiplying factor x Resolution)
Nr pulses = 0.25 / (4 x 0.0001) = 625 pulses/turn
Therefore:
Allthough the CNC accepts a maximum squarewave frequency of 400 kHz, when using Fagor
squarewave rotary encoders their output frequency is limited to 200 kHz; thus, the maximum
possible feedrate (F) will be:
Max. feedrate = (200.000 pulses/sec. / 625 pulses/turn) x 0.255 inch/turn
Max. feedrate = 80 inch/sec. = 4800 inch/min.
Example 6:
Resolution in "inches" with sinusoidal encoder
We would like to obtain a 0.0001 inch resolution by using a 250-line sinusoidal encoder mounted
on a leadscrew with a 5 turns/inch pitch.
We must calculate the multiplying factor "SINMAGNI" to be applied by the CNC to the pulses
provided by the encoder in order to obtain the desired resolution.
SINMAGNI = ballscrew pitch / (Nr pulses x Resolution)
SINMAGNI = 0.2 inch/turn / (250 x 0.0001) = 8
Therefore:
Although the CNC accepts a maximum squarewave frequency of 250 kHz, when using Fagor
sinusoidal rotary encoders, the output frequency is limited to 200 kHz; thus, the maximum possible
feedrate (F) will be:
Max. feedrate = (200.000 pulses/sec. / 250 pulses/turn) x 0.2 inch/turn
Max. feedrate = 160 inch/sec. = 9.600 inch/min.
Example 7:
Resolution in "degrees" with squarewave encoder
We would like to obtain a 0.0005º resolution by using a squarewave encoder mounted on a x10
reduction gear.
Since the CNC applies a x4 multiplying factor to squarewave signals, we would require an encoder
that provides the following number of pulses (lines) per turn.
Nr of pulses = º/turn / (multiplying factor x gear ratio x Resolution)
Nr of pulses = 360 / (4 x 10 x 0.0005) = 18,000 pulses/turn
Therefore:
Allthough the CNC accepts a maximum squarewave frequency of 400 kHz, when using Fagor
squarewave rotary encoders their output frequency is limited to 200 kHz; thus, the maximum
possible feedrate (F) will be:
Max. feedrate = (200,000 pulses/sec) / (18,000 pulses/turn)
Max. feedrate =11.111 turns/sec = 666.666 rpm
INCHES = 1 PITCH=0.25000 NPULSES = 625 SINMAGNI=0
INCHES = 1 PITCH=0.20000 NPULSES = 250 SINMAGNI=8
INCHES = 0 PITCH=36.0000 NPULSES = 18000 SINMAGNI=0