38 practical guide to electrical grounding – ERICO Practical Guide to Electrical Grounding User Manual
Page 46
38
Practical Guide to Electrical Grounding
Fig. 2-28
If a projection extends over 40 feet, a downlead at
(A) must be provided on the projection.
Fig. 2-29
Using the structural steel as the down conductor.
If Over 40 Feet,
Add A Down Lead
At "A"
A
CADWELD
Connection
3/4" Schedule
80 Non-Metallic
Conduit
Concrete Slab
Finished Grade
#2/0
2'-0" Min.
Clearance
1'-0"
Depth
CADWELD
Connection
3/4" x 10'-0"
Driven
Ground Rod
Fig. 2-31
Using the structural steel as the down conductor.
#2/0
CADWELD
Connection
Finished Roof
Fig. 2-32
Detail of conductor through the foundation.
+ 6" To 1'-0"
CADWELD
Type GR
Ground Rod
Connection
5/8" x 10'
Copperclad
Steel
Ground Rod
Below Grade
Bare Copper Conductor
1" PVC Conduit By
Electrical Contractor
Fig. 2-30
Clamp to cast iron or copper water pipe.
Grounding Book 4/14/99 10/5/99 6:01 PM Page 38 (Black plate)