15
Installation of an Earth Rod
Notice
If you install an extension outside of the main building, the following precautions are recom-
mended:
(1) Install the extension wire underground.
(2) Use a conduit to protect the wire.
Note
• The lightning protector for an extension is different from that for CO.
(1) Installation location of the earth rod ...... Near the protector
(2) Check obstructions ................................ None
(3) Composition of the earth rod ................. Metal
(4) Depth of the earth rod ............................ More than 50 cm
(20 inches)
(5) Size of the grounding wire .................... Thickness is greater
than 16 AWG
Notes
• The above figures are recommendations only.
• The length of earth rod and the required depth depend on the
composition of the soil.
CO
Lightning
Protector
Grounding
Wire
Main
Unit
(Underground)
Earth Rod
Installation of Lightning Protectors
Outside
Ground
SLT
PT
EXTN
EXTN
EXTN
EXTN
CO
CO
CO
Protectors
(Another Building)
(Main Building)
Terminal
Board
Main
Unit
Lightning
Protector
TEL
TEL