NI 9155 Operating Instructions and Specifications
10
ni.com
Removing I/O Modules from the Chassis
Complete the following steps to remove a C Series I/O module from the
chassis.
1.
Make sure that no I/O-side power is connected to the I/O module. If the
system is in a nonhazardous location, the chassis power can be on
when you remove I/O modules.
2.
Squeeze the latches on both sides of the module and pull the module
out of the chassis.
Connecting the Chassis to Earth Ground
You must connect the chassis grounding screw to earth ground. Refer to
Figure 4 for the location of the grounding screw. Complete the following
steps to connect to earth ground:
1.
Attach a ring lug to a 2.05 mm diameter (12 AWG) or larger wire.
2.
Remove the grounding screw from the grounding terminal on the right
side of the chassis.
3.
Attach the ring lug to the grounding terminal.
4.
Tighten the grounding screw to 0.5 N · m (4.4 lb · in.) of torque.
5.
Attach the other end of the wire to earth ground using a method
appropriate for the application.
Note
If you use shielded cabling to connect to a C Series I/O module with a plastic
connector, you must attach the cable shield to the chassis grounding terminal using 1.3 mm
diameter (16 AWG) or larger wire. Use shorter wire for better EMC performance.
For more information about earth ground connections, go to
ni.com/info
and enter the Info Code
earthground
.
Wiring Power to the Chassis
The NI 9155
requires an external power supply that meets the
specifications in the
section. The NI 9155
filters and
regulates the supplied power and provides power for all of the I/O modules.
You must connect a power supply to at least one pair of V and C terminals.
Optionally, you can connect a second power supply to the other pair of
V and C terminals. The chassis draws power from the power supply with
the higher voltage. The NI 9155 has one layer of reversed-voltage
protection. Complete the following steps to connect a power supply to
the chassis.
