MID-7604/7602 Power Drive User Guide
18
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Figure 6 shows the typical encoder wiring pin assignment for differential
line driver signal inputs.
Figure 6.
Typical Differential Line Driver Encoder Wiring Pin Assignment
If the encoder cable length is greater than 3.05 m (10 ft), use encoders
with line driver outputs for your applications. Power for a +5 V
encoder—generated by a power supply inside the MID-7604/7602—is
available on pin 7.
Note
If you require other encoder power voltages, reference an external power supply to
the Digital Ground signal on the 8-pin encoder terminal block.
The MID-7604/7602 supports differential inputs for Phase A, Phase B, and
Index signals. You can easily accommodate encoders with various phase
relationships by swapping the signals and/or connecting them to the
inverting inputs as specific applications require. The Index signal must
occur when both Phase A and Phase B signals are low, as shown in
Figure 7. If the Index polarity is inverted, try reversing the Index and Index
signals on differential encoders or using the Index input on single-ended
encoders.
Figure 7 shows the proper encoder phasing for CW (forward) motor
rotation.
Figure 7.
Encoder Signal Phasing, CW Rotation
1
2
3
4
5
6
7
8
Encoder A
Encoder A
Encoder B
Encoder B
Encoder Index
Encoder Index
+5 V
Digital Ground
Phase A
Phase B
Index
