3-12
The fire main and lightning rod of a building are not good grounding options. The ground wire of the
access controller should be connected to the grounding system in the equipment room.
When a grounding strip is unavailable
1) If earth is available nearby and allows a grounding body to be buried
Hammer an angle steel or steel pipe longer than 0.5 m (1.64 ft) into the earth. In this case, weld the
yellow-green PGND wire of the access controller onto the angle steel or steel pipe, and treat the joint for
corrosion protection.
Figure 3-17
Ground the access controller through a grounding body
(1)
(2)
(3)
(4)
(5)
(1) AC power socket
(2) Grounding terminal
(3) PGND wire
(4) Earth
(5) Angle steel
2) If no grounding body is allowed to be buried
As the access controller is AC powered, you can ground the access controller through a PE wire of the
AC power supply. In this case, make sure the PE wire is well connected to the ground in the power
distribution room or on the AC transformer side.
