PV Powered PVP260kW, Installation & Operation Manual

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PVP260kW Inverter
Installation and Operation Manual
!
CAUTION
The input and output circuits are isolated from the enclosure. System
grounding, when required by Sections 690-41, 690-42 and 690-43 of the
National Electric Code (NEC), ANSI/NFPA 70-1999, is the responsibility of
the installer.
!
WARNING
The AC output/neutral must not be bonded to ground within the equipment.
NOTE: The inverter is certified to UL1741 for installation without a neutral conductor.
Do NOT pull a neutral conductor from the AC service panel to the inverter.
The inverter is designed for use with 480VAC
Y
(WYE), three-phase power grids. The
voltage output is not selectable on these units. Do not attempt to change the AC output
voltage once it is set at the factory.
Use the National Electric Code to select the appropriate AC wire sizing for your
application. Correct wire sizing requires, at a minimum, considerations for ampacity,
temperature and conduit. In addition wire should be sized to minimize voltage drop.
Install the inverter on a dedicated branch circuit with a maximum 400A circuit breaker.
The inverter does not have internal AC fusing so it is important to size the branch circuit
protection appropriately.
When an inverter is installed on a 480VAC electrical panel the operational voltage range
is 422 VAC – 528 VAC for the inverter. Voltages outside this range will cause the inverter
to fault on a high or low voltage condition.
Connecting the AC and DC Wiring to the Inverter
The AC and DC connections are made through the user selected gland plates (plates and
dimensions are shown in
Appendix C - Mechanical Drawings ).
Connecting to the Electrical Grid
!
DANGER
Make sure the main breaker at the AC service panel is switched OFF before
connecting the AC wires to the inverter. This breaker should be switched ON
only after all wiring has been properly connected.
!
CAUTION
To avoid an increase in AC voltage to unacceptable values while the inverter
is connected, the grid impedance value at the connection point should be as
low as possible. By keeping the grid impedance value low, the system will
achieve higher efficiency.