Owner`s manual

Page 13
© 2009 Magnum Energy Inc.
2.2.1 Sizing the Grounding Electrode Conductors
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
2
) copper conductor
will serve as an AC Grounding Electrode Conductor (GEC –AC) for AC power conductors smaller
than and including #2 AWG (33.6 mm
2
) copper. See Table 2-1 for additional values.
DC Side - To size the DC Grounding Electrode Conductor, you must ¿ 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 ¿ gure 2-5): This method uses a separate Grounding Electrode for the DC system
and the AC system. In this method - since there are multiple connections to the DC Grounding
Electrode (GEC – DC) - the size of the DC Grounding Electrode Conductor cannot be smaller than
the largest conductor in the DC system (usually the battery-to-inverter cable).
The DC Grounding Electrode (GE – DC) must be bonded to the AC Grounding Electrode (GE – AC)
to make a grounding electrode system; this bonding conductor (BC) cannot be smaller than the
largest Grounding Electrode Conductor, either AC or DC.
Table 2-1, AC Grounding Electrode Conductor Sizing
Figure 2-5, Multiple Connections to DC Ground Rod (Method 1)
AC
DC Service
Panel
AC Service
Panel
DC Electrical SystemAC Electrical System
Neutral
Positive
Negative
DC
Grounding
System
Negative
SBJ
GC
GE
GEC-AC
EGC - AC
AC Ground DC Ground
SBJ
EGC - DC
GC
Neutral
Hot
GEC-DC
GBB GBB
Grounding Electrode
(AC and DC sides shared)
MS-PAE Series Inverter/Charger
Size of Largest
Ungrounded Conductor
(Copper)
Minimum Size of
Grounding Electrode
Conductor (Copper)
2AWGorsmaller #8AWG
1or1/0AWG #6AWG
2/0or3/0AWG #4AWG
Over 3/0 AWG
through 350kcmil
#2 AWG
AC Grounding Electrode Conductor Sizing
Installation