Sizing The Grounding Electrode Conductors (Gec); Figure 2-13, Method 1 - Dc Ground Rod With Multiple Connections; Table 2-3, Ac Grounding Electrode Conductor (Gec-Ac) Sizing - Magnum Energy Sensata MagnaSine Owner's Manual

System Grounding – Takes one of the current-carrying conductors (Grounded Conductor–GC) and
attaches it to the common ground point (Ground Busbar–GBB), usually by a System Bonding Jumper
(SBJ) in each electrical service disconnect panel. On the DC side that is the negative conductor;
on the AC side it's the neutral conductor. The closer the grounding connection is to the source,
the better the protection from surges due to lightning.

2.4.1 Sizing the Grounding Electrode Conductors (GEC)

AC Side – The size of the AC grounding electrode conductor (GEC–AC) depends on the size of the
largest ungrounded conductor feeding the AC load center. A #8 AWG (8.4 mm
will serve as an AC grounding electrode conductor for AC power conductors smaller than and
including #2 AWG (33.6 mm
Table 2-3, AC Grounding Electrode Conductor (GEC–AC) Sizing
Size of Largest Ungrounded
Conductor (Copper)
2 AWG (33.6 mm
1 AWG (42.4 mm ) or 1/0 AWG (53.5 mm
2
2/0 AWG (67.4 mm
2
Over 3/0 AWG (85.0 mm
DC Side – To size the DC grounding electrode conductor (GEC–DC), you must fi rst determine
which one of the following three methods will be used to connect the DC and AC grounding points
in the inverter's two electrical systems to the common "earth" ground:
Method 1 (see Figure 2-13): This method uses a separate grounding electrode (GE) for the
DC system and the AC system. In this method—since there are multiple connections to the DC
grounding electrode (GE)—the size of the DC grounding electrode conductor (GEC–DC) cannot
be smaller than the largest conductor in the DC system (usually the battery-to-inverter cable).
The DC grounding electrode (GE) must be bonded to the AC grounding electrode (GE) to make
a grounding electrode system; this bonding conductor (BC) cannot be smaller than the largest
grounding electrode conductor—either AC or DC.
AC Service
Neutral
GBB
Grounding Electrode
(AC side dedicated)
Figure 2-13, Method 1 – DC Ground Rod with Multiple Connections
© 2017 Sensata Technologies
) copper. See Table 2-3 for additional values.
2
) or smaller
2
) or 3/0 AWG (85.0 mm
) through 350 kcmil
2
AC Electrical System
MS-PAE Series Inverter/Charger
Panel
Hot
AC
GC
Neutral
SBJ
AC Ground
EGC-AC
GEC-AC
GE
(using multiple grounding electrodes)
Minimum Size of Grounding
Electrode Conductor (Copper)
#8 AWG (8.4 mm
) #6 AWG (13.3 mm
2
) #4 AWG (21.1 mm
2
#2 AWG (33.6 mm
DC Electrical System
Positive
DC
GC
Negative
DC Ground
EGC-DC
Grounding
System
GEC-DC
GE
BC
Grounding Electrode
(DC side dedicated)
Installation
) copper conductor
2
)
2
)
2
)
2
)
2
DC Service
Panel
Negative
SBJ
GBB
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