Xantrex Trace SW4024, Installation Manual

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© 2002 Xantrex Technology Inc.
P/N 975-0041-01-02 Rev A 03/02
1
1.0 INTRODUCTION
INTRODUCTION
The Grid Tie Interface (GTI) is an integrated assembly used with the Trace™
SW Series II inverter/charger with Revision 4.2 (or higher) software. This new device
provides active anti-islanding protection and reduces current Total Harmonic
Distortion (THD) as required in UL-1741-2000.
The Grid Tie Interface is an accessory, which is connected between the grid, the
AC loads, and the SW Series II inverter to optimize the “SELL” feature. While there
is a small inductor in the GTI, this device is not a “filter”; rather it contains an
additional control microprocessor, which connects to the SW Series II with a
communications cable.
When the GTI is connected and the Inverter “SELL” mode is selected, the
microprocessor of the GTI takes control of the SW Series II and operates the inverter
“SELL” feature. The GTI affords a dedicated microprocessor and new, sophisticated
control algorithms that are able to optimize the sell function.
The SW Series II with the GTI meets all power quality requirements of UL1741,
including harmonic distortion, power factor, and anti-islanding requirements. In
addition, it has increased the SW Series II’s efficiency in SELL mode to within 1% of
the impressive off-grid efficiency of the SW.
The GTI also contains an automatic transfer/shorting relay, which the SW
Series II uses to disconnect the GTI from the circuit when it is not needed, for
example when the SW Series II is charging batteries from the grid. This is also used
to disconnect the GTI so that it does
NOT NOT NOT NOT NOT represent a phantom load or parasitic
loss to the system.
All new SW Series II units (manufactured since December of 2001) are
equipped to allow the GTI to be installed in the field. The SW Series II inverter is
Certified to UL1741 for off grid and backup power applications. The SW can be
connected to the grid as a battery charger; however, it is
NOT NOT
NOT NOT
NOT approved to use the
SELL feature (net meter) without the GTI accessory. The GTI carries all necessary
approvals and markings to allow a safety inspector to approve the installation for net
metering.