Xantrex GT5.0-NA-240, Руководство пользователя

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Installation
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The short circuit current (I
sc
) rating of the array at any temperature must not
exceed the I
sc
rating of the inverter. For maximum solar energy harvest, it is
recommended that the effective power output of the array be matched with the
input power capacity of the inverter.
Guidelines for Matching PV Array Size to Xantrex Grid Tie Solar Inverter Input
• Consider the expected V
oc
of the string under all possible conditions. The
panel manufacturer provides a V
oc
rating per panel, but it is usually rated at
25
°
C (77
°
F). Ensure that the V
oc
rating at the coldest ambient temperature
does not exceed 600 Vdc. Panel voltage increases in cold temperatures—the
panel manufacturer should be able to provide a coefficient of voltage increase
per degree.
• The NEC also has required temperature/voltage deratings that must be used;
these can be found in Article 690 of the NEC. You need to determine the
coldest temperatures expected on the site, and size the array strings
accordingly. To prevent inverter damage, the array’s maximum DC voltage in
the coldest expected temperature, with both manufacturer coefficient and
NEC derating, must not exceed 600 Vdc.
• Panel voltage decreases in high temperatures. This will affect the panels’ V
MPP
and V
oc
. Again, the manufacturer’s coefficient must be used with the highest
expected temperature to determine the minimum V
MPP
and V
oc
.
Mounting the Inverter
Dimensions and Knockout Locations
Inverter dimensions and knockout locations are shown in Figure 2-1.
Four 27 or 35 mm (1 or 1-3/8 inch) dual knockouts are provided on the back and
bottom of the unit to accommodate wiring. -POS models have four 22 mm
(7/8 inch) knockouts on the back of the wiring/disconnect box.
Four 27 mm (1 inch) conduit holes on the sides of the wiring/disconnect box (two
on each side) are filled with plastic plugs (thread size Pg 21). These plugs can be
removed to insert conduit nipples as required for multiple inverter installations.
Side conduit holes may be used to accommodate network communication cables
connected between multiple inverters.
Note:
The GT PV array sizing tool is available at www.xantrex.com .
Important: Do not drill, cut, or punch holes in the wiring/disconnect box. Use only the
knockouts provided for conduit entry.