National Instruments UMI-4A, Руководство пользователя

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© National Instruments Corporation 15 UMI Accessory User Guide — UMI-4A
Encoder Terminal Block
For incremental encoder connections, each UMI-4A axis has a separate
8-position terminal block. UMI-4A accepts either single-ended TTL or
differential line driver inputs. You can connect open-collector encoders to
the UMI-4A accessory by installing a 2.2 k
Ω
pull-up resistor to +5 V.
Note Encoders with line driver outputs are recommended for all applications and must be
used if the encoder cable length is greater than 10 feet.
Power for the encoders is internally routed from the power input terminal
block and is available on pin 7 (+5 V). You must supply a +5 V source to
the power input terminal block for proper operation. Refer to Figure 12 to
help you locate the encoder terminal blocks on your UMI-4A accessory.
Figure 16 shows the wiring for the differential encoder.
Note
The dotted loop indicates a shielded cable.
Figure 16. Differential Encoder Wiring
Figure 17 shows the wiring for the single-ended encoder.
Figure 17. Single-Ended Encoder Wiring
1
2
3
4
5
6
7
8 Phase A
Phase B
Phase B
Index
Index
+5 V (Output)
Digital Ground
Phase A
Shield
1
2
3
4
5
6
7
8 Phase A
Phase B
Index
+5 V (Output)
Digital Ground
Shield