+5 V Power Source; User 1 And User 2 - National Instruments X Series User Manual

+5 V Power Source

The +5 V terminals on the I/O connector supply +5 V referenced to D GND. Use these terminals
to power external circuitry.
Caution
any other voltage source on the X Series device or any other device. Doing so can
damage the device and the computer. NI is not liable for damage resulting from such
a connection.
The power rating on most devices is +4.75 VDC to +5.25 VDC at 1 A.
Refer to the device specifications to obtain the device power rating.
Note (PCI Express X Series Devices)
supply less than 1 A of +5 V power unless you use the disk drive power connector.
Refer to the
information.

USER 1 and USER 2

The USER 1 and USER 2 BNC connectors allow you to use a BNC connector for a digital or
timing I/O signal of your choice. The USER 1 and USER 2 BNC connectors are routed internally
to the USER 1 and USER 2 screw terminals, as shown in Figure 3-1.
Figure 3-1. USER 1 and USER 2 BNC Connections
Never connect the +5 V power terminals to analog or digital ground or to
PCI Express Device Disk Drive Power Connector
Internal
Connection
USER 1 BNC
D GND
USER 2 BNC
D GND
Some PCI Express X Series devices
Screw
Terminal
Block
USER 1
USER 2
D GND
+5 V
AI GND
AI SENSE
AI SENSE 2
APFI 0
CHS GND
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