National Instruments PCIe-6323, User Manual

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X Series User Manual
Getting Started with X Series USB Devices
The following sections contain information about X Series USB device best practices and
features.
USB Device Chassis Ground
(NI USB-63
xx
Screw Terminal Devices) For EMC compliance, the chassis of the USB Screw
Terminal X Series device must be connected to earth ground through the chassis ground.
The wire should be AWG 16 or larger solid copper wire with a maximum length of 1.5 m (5 ft).
Attach the wire to the earth ground of the facility’s power system. For more information about
earth ground connections, refer to the document,
Grounding for Test and Measurement Devices ,
by going to
ni.com/info
and entering the Info Code
emcground
.
You can attach and solder a wire to the chassis ground lug of the USB X Series device, as shown
in Figure 1-1. The wire should be as short as possible.
Figure 1-1. Grounding an NI Screw Terminal USB-63x x Device through
the Chassis Ground Lug
(NI USB-63xx BNC Devices) You can attach a wire to a CHS GND screw terminal of any
NI BNC USB-63 xx device. Use as short a wire as possible. In addition, the wires in the shielded
cable that extend beyond the shield should be as short as possible.
Note (NI USB-636
x
Mass Termination Devices) USB Mass Termination
X Series devices have chassis ground connection through the I/O connector.