National Instruments cRIO-9068, User Manual

Figure 5. cRIO-9068 Grounding Screw

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1. Grounding Screw

For EMC compliance, you must connect the cRIO-9068 to earth ground through the chassis
ground screw. Use wire that is 2.0 mm

2

 (14 AWG) solid copper wire with a maximum length

of 1.5 m (5 ft). Attach the wire to the earth ground of the electrode system of the facility.

Caution

If you use shielded cabling to connect to a C Series module with a plastic

connector, you must attach the cable shield to the chassis grounding terminal using
2.0 mm

2

 (14 AWG) or larger wire. Attach a ring lug to the wire and attach the wire

to the chassis grounding terminal. Solder the other end of the wire to the cable
shield. Use shorter wire for better EMC performance.

For more information about ground connections, visit 

ni.com/info

 and enter the Info Code

emcground

.

Internal Real-Time Clock

The cRIO-9068 contains an internal real-time clock that maintains system time when the
cRIO-9068 is powered off. The system clock of the cRIO-9068 is synchronized with the
internal real-time clock at startup. You can set the real-time clock using MAX, or you can set
the clock programmatically using LabVIEW.

Refer to the specifications on 

ni.com/manuals

 for the real-time clock accuracy specifications.

Battery

The cRIO-9068 contains a lithium cell battery that stores the system clock information when
the cRIO-9068 is powered off. There is only a slight drain on the battery when power is
applied to the cRIO-9068 power connector. The rate at which the battery drains when power is
disconnected depends on the ambient storage temperature. For longer battery life, store the
cRIO-9068 at a cooler temperature and apply power to the power connector. Refer to the
specifications on 

ni.com/manuals

 for the expected battery lifetime.

The battery is not user-replaceable. If you need to replace the battery, contact NI. Refer to the
specifications on 

ni.com/manuals

 for information about battery disposal.

File System

LabVIEW mounts USB devices to the 

media/sdx1

 directory and creates symbolic

links 

/u

, 

/v

, 

/w

, or 

/x

 to the media mount point, starting with 

/u

 if it is available. To prevent

any file corruption to external storage devices, verify that any file IO operations with the

NI cRIO-9068 User Manual

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