![background image](http://html.mh-extra.com/html/national-instruments/784xr/784xr_user-manual_709603050.webp)
Chapter 2
Hardware Overview of the NI 78xxR
©
National Instruments Corporation
2-29
R Series Intelligent DAQ User Manual
(NI 784
x
R/785
x
R Devices)
All NI 784
x
R/785
x
R devices have a
user-replaceable socketed fuse to protect the supply from overcurrent
conditions. When an overcurrent condition occurs, check your cabling to
the +5 V terminals and replace the fuse as described in the
Replacement (NI 784xR/785xR Only)
section.
Caution
Never
connect the +5 V power terminals to analog or digital ground or to any
other voltage source on the NI 78
xx
R 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 to +5.25 VDC at 1 A.
Refer to the
NI R Series Intelligent DAQ Specifications
document, available
at
ni.com/manuals
, to obtain the power rating for your device.
Device Fuse Replacement (NI 784
x
R/785
x
R Only)
NI 784
x
R/785
x
R devices have a replaceable fuse, Littelfuse part number
0453004 (NI part number 766247-01), that protects the device from
overcurrent through the power connector.
To replace a broken fuse in the NI 784
x
R/785
x
R, complete the following
steps:
1.
Power down and unplug the computer or PXI chassis.
2.
Remove the PCI device from the expansion slot on the computer, or
the PXI device from the PXI slot in the PXI chassis.