Xantrex GT2.8-AU-QC-230, Руководство пользователя

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Planning the Installation
975-0466-01-01 2–7
3. To achieve maximum energy harvest from your array, ensure that the V
MP
(voltage at maximum power) does not drop below 195/240 Vdc or increase
above 550 Vdc under most conditions.
Guidelines to help you meet these requirements:
• 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. Ensure that the V
OC
rating at the coldest ambient temperature does not
exceed 600 V
OC
. Panel voltage increases in cold temperatures—the panel
manufacturer should be able to provide a coefficient of voltage increase per
degree.
• Panel voltage decreases in high temperatures. This will affect the panels’
V
MP
. Again, the manufacturer’s coefficient must be used with the highest
expected temperature to determine the minimum V
MP
.
Once you know the specifications of your panels, all these factors will help
determine the maximum and minimum number of panels that can be used.
Visit the Support page at www.xantrex.com to use an online PV array sizing tool.
Grounding Requirements
AC Grounding
AC system grounding is governed by local codes. The GT2.8-AU and GT5.0-AU
inverters will function properly in AC systems with a grounded neutral or with
two ungrounded lines. The GT Inverter must be provided with an equipment
grounding conductor connected to the grounding terminal on the AC output
connector (GT2.8-AU) or in the wiring compartment (GT5.0-AU) and routed to
the ground bus of the AC load panel to which the inverter is connected.
DC Grounding
The GT Inverter is designed to work with ungrounded PVsystems (neither the
PV+ nor the PV– are connected to earth). The array frames and other PV
equipment must have equipment grounding connections as required by applicable
codes.
WARNING: Shock hazard
The GT Inverter must be grounded in accordance with the following and with all
applicable codes.