Owners Manual

© 2013 Magnum Energy, Inc.Page 23
I nst alla t ion
2 .6 .1 Sizing t he Grounding Elect r ode Conduct ors
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. One 8.4 mm
2
(#8 AWG) copper
conductor will serve as an AC grounding electrode conductor (GEC-AC) for AC power conductors
smaller than and including 33.6 mm
2
(#2 AWG) copper. See
Table 2-3 for additional values.
Table 2 - 3 , AC Grou ndin g Elect rode Conduct or Sizin g
Size of Largest
Un gr ounded Conduct or
Minim um Size of
Groun ding Ele ct rode Conductor
33.6 mm
2
(#2 AWG) or smaller 8.4 mm
2
(#8 AWG)
42.4 to 53.5 mm
2
(#1 to #1/0 AWG)
13.3 mm
2
(#6 AWG)
67.4 or 85.0 mm
2
(#2/0 or #3/0 AWG)
21.1 mm
2
(#4 AWG)
85.0 mm
2
(Over #3/0 AWG) thru 350 kcmil
33.6 mm
2
(#2 AWG)
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:
• Met h od 1 ( Figure 2 - 1 1 ) : 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 (GE-DC)—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-DC) must be bonded to the AC grounding electrode (GE-AC)
to establish a grounding electrode system; this bonding conductor (BC) cannot be smaller than
the largest grounding electrode conductor (GEC), either AC or DC.
Figure
2 - 1 1 , Multiple Conne ct ion s t o DC Gr ound Rod ( M et hod 1 )
AC
DC Service
Panel
AC Service
Panel
DC Electrical SystemAC Electrical System
Neutral
Positive
Negative
DC
Grounding
System
Negative
SBJ
GC
GEC-AC
EGC - AC
AC Ground DC Ground
SBJ
EGC - DC
GC
Neutral
Hot
GEC-DC
GE GE
GBB GBB
Grounding Electrode
(DC side dedicated)
Grounding Electrode
(AC side dedicated)
MS-PE Series Inverter/Charger
BC