Figure 2-4; alternate grounding, pn-3 and pn-4, Pre-installation, Continued – Alpha Technologies PN-4 User Manual
Page 14: 3 enclosure grounding
2. Pre-Installation
14
031-103-B0-003 Rev. C
© 2002
TM
2.3
Enclosure Grounding,
continued
Lightning Protection (Optional)
1/2" x 8' copper ground rod, four places, driven about 2 feet (typical) from the corners of the pad.
#2 bare copper wire loop terminated to each ground rod and buried below grade 2 to 12 inches.
Corrosion-proof connections (25+ year life-span) and hardware suitable for direct burial MUST be used.
#2 bare copper wire from loop to the enclosure
When the electrical supply is a primary service (not a secondary or feeder service) a #2 bare copper wire
must be bonded to the lightning protection loop to the Grounding Electrode Conductor where they are
closest.
Service Grounding (required)
#2 bare copper wire from Service Neutral / Ground Bar down 30 inches and out 20 feet beyond the pad
edge. This is often called a UFER ground (Ground Ring in the NEC).
Opening for
Sweeps
Opening for
Sweeps
Enclosure Footprint
20 feet (minimum)
2 f
ee
t
(m
in)
8
211(&7,21
Г
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:,7+
7
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1
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25
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8
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7
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25
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30
i
n
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hes
Side view
UFER Ground
SE
conduit &
wires
GEC
#2 bare
copper
wire
No
separation
is required.
#2 AWG
#2 AWG
Opening for
Sweeps
1
2
3
4
5
4
5
1
2
3
Figure 2-4; Alternate Grounding, PN-3 and PN-4