6.17 Square-Wave Output RS 422
Optimal Connection Circuit
Signal Curve
In order to avoid electromagnetic interference, the cable adaptation with a terminal resistor of
R
0
= 120 Ω is necessary. When connecting more than one parallel signal input to an encoder output
signal (e�g� linear motors with parallel connection to position controller, speed controller or acceleration
controller) ensure that the resulting terminal resistance of these inputs is R
0res
≈ 120 Ω.
NAS high:
Encoder functioning properly, input signals within
tolerance range
NAS low:
Check the measuring system
a:
Minimum edge separation as a function of the
interpolation factor and traversing speed
Image 19
Image 20
RS 422 line driver
R
0
R
5 V
5 V
R = 120
0
Ω
RS 422 line receiver
(e.g. AM 26 LS 32, MC 34 86)
NAS
Z
Z
Z
1+
2+
0+
/
/
Z
Z
Z
1–
2–
0–
/
/
360° (Signal period)
NAS
Z
2
Z
0
Z
1
a
0
0
0
0
90° (Phase difference)
27/58
KIT
L
-Series
