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2010 Magnum Energy, Inc
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Installation
Method 2 (see Figure 2-17):
When the AC and DC service panels are near each other, then
the AC Grounding Electrode Conductor (GEC – AC) and DC Grounding Electrode Conductor (GEC
– DC) can be connected to a single grounding electrode. In this method — since there are multiple
connections to the DC Grounding Electrode (GEC – DC) — the size of the DC grounding electrode
conductor can not be smaller than the largest conductor in the DC system (usually the battery-
to-inverter cable).
A C
D C S e rvice
P a n e l
A C S e rvice
P a n e l
D C E lec tric al S y s tem
A C E lec tric al S y s tem
N eutral
Positive
N egative
D C
G rounding
S y s tem
N e g a tive
S B J
GC
GE
GE C -A C
E GC - A C
AC Ground
D C Ground
S B J
E GC - D C
GC
N e u tra l
H ot
GE C -D C
GB B
GB B
Grounding Electrode
(AC and D C sides shared)
R D S e rie s In ve rte r/C h a rg e r
Figure 2-17, Multiple Connections to DC Ground Rod (Method 2)
Method 3 (see Figure 2-18):
The AC Grounding Electrode Conductor (GEC – AC) is bonded to
the DC ground point and the DC Grounding Electrode Conductor (GEC – DC) is the
only connection
to the grounding electrode, which must be a rod, pipe, or plate electrode.
In this method, since there is only one connection to the ground rod, the DC grounding electrode
conductor is not required to be larger than #6 AWG (13 mm
2
) copper. The reasoning for allowing
this smaller grounding electrode conductor is that it is only required to stabilize the system voltage
with respect to earth and the other properly sized conductors in each electrical system will safely
carry any fault currents if they occur.
A C
D C S e rvice
P a n e l
A C S e rvice
P a n e l
D C E lec tric al S y s tem
A C E lec tric al S y s tem
N eutral
Positive
N egative
D C
G rounding
S y s tem
N e g a tive
S B J
GC
GE C -A C
E GC - A C
AC Ground
D C Ground
S B J
E GC - D C
GC
N e u tra l
H ot
GE C -D C
GE
GB B
GB B
Grounding Electrode
(D C side dedicated)
R D S e rie s In ve rte r/C h a rg e r
Figure 2-18, Single Connection to DC Ground Rod (Method 3)
