National Instruments UMI-4A, Руководство пользователя

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UMI Accessory User Guide — UMI-7764 8 www.natinst.com
Figure 6. Encoder Signal Phasing—CW Rotation
The encoder inputs are filtered by both analog and digital noise filters. You
must use cables with twisted pairs and an overall shield for improved noise
immunity. When connecting the encoder to the UMI-7764, you should use
at least 24-AWG wire.
Caution Using an unshielded cable allows noise to corrupt the encoder signals, which
results in lost counts, reduced accuracy, and other erroneous encoder and controller
operations.
Limit Switch Terminal Block
Each UMI-7764 axis motion I/O terminal block has five terminals for
Forward and Reverse Limit and Home Input switch connections. Refer to
Figures 1 and 2 to help you locate the limit switch terminals on your
UMI-7764 accessory. See Figure 7 for the UMI-7764 limit switch terminal
block pinout.
Figure 7. UMI-7764 Limit Switch Terminal Block Pin Assignment
You can configure the axis Inhibit Input signals as active-low or active-high
inputs using switch S2. Setting S2 to the bottom configures the signal as
active-low; setting S2 to the top configures the signal as active-high. The
Inhibit Input signals include a 3.3 k
Ω
pull-up resistor on their inputs.
Phase A
Phase B
Index
Forward Limit
Home Input
Reverse Limit
Inhibit Input
Digital Ground