3-11
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.
Figure 3-16
Ground the access controller through a grounding strip
(1)
(2)
(3)
(4)
(1) AC power socket
(2) Grounding terminal
(3) PGND wire
(4) Grounding strip
