VIONiC REXM20/REXT20 installation guide
16
Output specifications
Digital output signals
Form – Square wave differential line driver to EIA RS422A (except limits P and Q)
Incremental
*
2 channels A and B in quadrature (90° phase shifted)
Signal period P
Resolution S
A
B
Z
Reference
*
Synchronised pulse Z,
duration as resolution.
Bi-directionally repeatable.
†
Limits
Open collector output, asynchronous pulse
(Not available with ‘A’ cable termination)
Repeatability < 0.1 mm
~
Length of limit actuator
P Q
Active high
E−
or 3-state alarm
Differentially transmitted signals forced open circuit for > 15 ms when alarm conditions valid.
Alarm asserted when:
– Signal amplitude < 20% or > 135%
– Readhead speed too high for reliable operation
> 15 ms
NOTE:
A wide reference mark option, outputting
a reference pulse for the duration of the signal
period is available.
Contact your local Renishaw representative for
more information.
Resolution
option code
P
(µm)
S
(µm)
D
20
5
X
4
1
Z
2
0.5
W
0.8
0.2
Y
0.4
0.1
H
0.2
0.05
M
0.16
0.04
P
0.1
0.025
I
0.08
0.02
O
0.04
0.01
Q
0.02
0.005
R
0.01
0.0025
Alarm
Line driven
(Asynchronous pulse)
(Not available with ‘A’ cable termination)
*
Inverse signals not shown for clarity.
†
Only calibrated reference mark is bi-directionally repeatable.