Wire Size And Over-Current Protection Requirements; Current Rating; Minimum Wire Gauge; Over-Current Protection - Xantrex XW4024-120/240-60 Installation Manual

Wire Size and Over-current Protection Requirements

Current Rating

Minimum Wire Gauge

Over-current Protection

Long-distance wire runs

975-0239-01-01
The wiring, over-current protection devices (fuses and circuit breakers), and installation
methods used must conform to all national and local electrical code requirements.
Wiring must be protected from physical damage with conduit or a strain relief clamp.
To preserve signal integrity on communication cables, the BTS, auxiliary output, and
network cables must pass through a different conduit than the conduits used for PV and
battery cables. You should pull the BTS cable through the conduit first as the connector
may not fit if other wires have been pulled first.
The XW SCC PV input is rated for 60 A maximum I
the array size or sunlight angle, the safe minimum wire size must be chosen for maximum
array short-circuit current. Consult PV array manufacturer specifications.
For installations where the PV array output is the maximum allowable 60 A I
minimum allowable wire gauge is #6 AWG (16 mm
insulation rating. This wire gauge is determined by electrical code requirements regarding
conduit knockout sizes, wire bending radius, and space available within the XW SCC
wiring compartment.
No crimp-on terminals or lugs are required.
Over-current protection must be installed to protect the XW SCC from short circuits and
to provide a means of disconnecting the XW SCC. Consult local electrical codes to
establish the correct fuse or circuit breaker rating.
Battery Circuit The NEC requires the battery circuit to be protected with a device rated
for 125% of the rating of the circuit. The DC-rated fuse or circuit breaker between the
battery and the XW SCC must be rated for 1.25 × 60 A (the maximum current rating of
the XW SCC).
PV Circuit A PV disconnect device between the PV array and the XW SCC must be
rated for 60 A.
If there is a significant distance between the PV array and the XW SCC or between the
XW SCC and the battery, larger wires can be used to reduce the voltage drop and improve
performance. Refer to Table 4-4 or Table 4-5.
WARNING: Equipment damage
Do not connect an array capable of delivering over 60 A I
2
#6 AWG (16 mm ) may be used to reduce resistive losses but should not be installed directly into
the XW SCC. Use a splicer block or similar to connect wires of different gauges together. Follow
manufacturer's recommendations for torque and mounting.
This manual for use by qualified personnel only
. Since PV outputs can vary due to
sc
2
) copper wire with a 90 °C (194 °F)
to the XW SCC. Wire sizes larger than
sc
Wiring
, the
sc
4–11