Parker 401XR Series, Product Manual

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401/402XR Series Product Manual
Chapter 3 - Component Specifications
17
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Parker Hannifin Corporation
1140 Sandy Hill Road
Irwin, PA 15642
Chapter 3 - Component Specifications
Linear Encoders
Description Specification
Input Power 5 VDC +/- 5% 150mA
Output (incremental) Square wave differential line driver (EIA RS422) 2
channels A and B in quadrature (90) phase shift
Reference (Z channel)
– see below
for additional information
Synchronized pulse, duration equal to one resolution
bit. Repeatability of position is unidirectional moving
toward non-motor end.
Positional Accuracy +/- 3 microns after linear slope correction
Maximum Speed
– see page 14 for
additional information
1.0 micron resolution = 3.0 meters/sec
0.5 micron resolution = 1.5 meters/sec
0.1 micron resolution = 0.3 meters/sec
Z-Channel Position Reference
The Z channel is an output on the encoder. Many servo controllers support this input. The Z
channel on the 401/402XR is located at mid travel. The Z channel is a unidirectional device. This
means that the final homing direction must occur in one direction. The 401/402XR is set so that the
final home direction is to be toward the non-motor end of the table. The repeatability of the Z
channel is equal to +/- 2 resolution counts of the encoder (except for 0.1 micron scales which have
a repeatability of +/-1 mi
crons). Thus the repeatability of the “Z” channel equals:
Encoder Resolution Z Channel Repeatability
1 micron +/- 2 micron
0.5 micron +/- 1 micron
0.1 micron +/- 1 micron
NOTE: Home repeatability is also very dependent on controller input speed and homing algorithms.
The above repeatability does not include possible controller tolerance. Additionally, to achieve the
highest repeatability the final homing speed must be slow. Slower final speed usually results in
higher repeatability.
NOTE
: The “Z” channel output is only one resolution count wide. Thus the
on-time may be very
brief. Due to this some controllers may have difficulty reading the signal. If you are experiencing
the positioner not finding the “Z” channel during homing, try reducing final homing speed; also refer
to your controller manual for frequency rates of the “Z” channel input.