Chapter 3
Signal Connections
©
National Instruments Corporation
3-13
NI 951x User Manual
You can set the index reference criteria in software to change the line state
of Phase A and Phase B used in the Index search. Refer to the
NI SoftMotion
Module
book of the
LabVIEW Help
for more information about encoder
settings.
Encoder Input Circuit
The NI 951x drive interface modules support RS-422 differential and
single-ended inputs for Phase A, Phase B, and Index signals, and provide a
+5 V output for encoder power.
You also can set the encoder active state for Phases A, Phase B, and Index
to high or low using software. Refer to the
NI SoftMotion Module
book of
the
LabVIEW Help
for more information.
Tip
Refer to the
Signal Connection Recommendations
section of Chapter 4,
Accessory
and Cable Connections
, for additional wiring and cabling recommendations.
Figures 3-11 and 3-12 show simplified schematic diagrams of the encoder
input circuit connected to differential and single-ended inputs.
Figure 3-11.
Differential Encoder Input Circuit
Figure 3-12.
Single-Ended Encoder Input Circuit
Receiver
Phase +
Phase –
Encoder
NI 951x
+5 V
COM
Receiver
Phase+
Encoder NI
951x
No
Connection
Phase–
+5 V
COM
+5 V
Com