H3C Technologies H3C WX5000 Series Access Controllers - Manual (Page 29)

3-9
Make sure that there is at least 1 U (44.45 mm, 1.75 in.) height away from neighbor devices for heat
dissipation.
Installing the Access Controller on a Workbench
In case the standard 19-inch rack is not available, you can install the access controller on a clean
workbench. When installing the access controller on a workbench,
z
Make sure that the workbench is flat, sturdy and well earthed.
z
Keep the environment well ventilated and reserve a clearance of 10 cm (3.9 in.) around the chassis
for heat dissipation.
z
Place no heavy objects on the access controller.
z
Keep at least a vertical distance of 1.5 cm (0.59 in.) between access controllers when they are
placed one above the other.
Connecting the Ground Wire
The correct connection of the protection ground (PGND) wire of the access controller is an essential
safeguard against lightning strokes and electromagnetic susceptibility (EMS) interference. You must
first correctly connect the PGND wire when installing the access controller.
The power input end of the access controller is connected with a noise filter, whose central ground is
directly connected to the chassis, forming the chassis ground (also known as PGND). This chassis
ground must be securely grounded so that induced and leaked electricity can be safely discharged to
the ground, enhancing the anti-EMS capability of the access controller. Ground the access controller as
follows:
When a grounding strip is available
1) Remove the grounding terminal screw located at the right back of the chassis, as shown in Figure
3-16 .
2) Fasten the wiring terminal of the yellow-green PGND wire of the access controller to the grounding
terminal screw you removed in step 1.
3) Put the grounding terminal screw back to the grounding hole on the chassis and fasten it.
4) Fasten the other end of the yellow-green PGND wire to the grounding stud for the access controller
on the grounding strip.
5) On the grounding strip, use a nut to fasten the grounding stud that is attached with the PGND wire.