MidNite Solar Barcelona Breaker Box, Manual

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MNBCLNA BB Manual
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DC Over-Current Protection
•
The NEC requires both over-current protection (UL489 standards) and a disconnect switch.
If a circuit breaker is used as the over-current protection device, it can also be used as the
required DC disconnect.
•
The DC over-current protection device must be installed on the positive DC cable. It must
be correctly sized according to the size of DC cables being used, which means it is required
to open before the cable reaches its maximum current carrying capability.
Grounding
•
The negative battery conductor should be solidly bonded to
the grounding system at only one point in the system. The size
for the conductor is determined by the size of the largest
phase conductor, per the NEC/CEC.
NOTE
– If using the optional ground fault (GF) toroid in the
Barcelona, DO NOT solidly ground Batt- to ground. This will
prevent the GF sensor from working.
•
Figure 1 shows the Barcelona equipment ground terminal.
•
Figure 2 shows the Ground busbar in the Breaker Box .
•
Use #6 AWG (or larger based on grounding system design) ground
electrode conductor.
Arc Fault -
The NEC requires a PV system DC circuit operating at 80VDC
or greater must be protected by an arc fault (AF) circuit interrupter.
Ground Fault -
Since 2008 the NEC requires a DC Ground Fault (GF)
Protection device on all PV systems to indicate when a GF condition
exists.
Figure 2
The Barcelona may be used in a positive, negative, or
ungrounded installation. For a grounded system, bond
either Battery Negative to ground, or bond Battery
Positive to ground (but not both at the same time!!).
CAUTION!
Figure 1