Outback Power Systems GS8048 Operator Manual - Manual (Page 21)

Operation
900-0020-01-00 Rev B 19
The inverter does not filter or clean up the power from the AC source. The voltage and power quality
received by the output loads is the same as that of the source. If the voltage or quality do not meet
the inverter’s input requirements (see page 17), it will disconnect and return to the inverting mode.
 If the AC source meets the inverter’s requirements but is irregular, any fluctuations will be transferred to the
loads. If the loads are sensitive, it may be necessary to improve the quality of the AC source.
 To ensure a smoother transition, it may be advisable to raise the inverter’s lower acceptance limit. The
default setting is 108 Vac on each leg. A higher setting will cause the inverter to transfer sooner in the event
of a quality problem.
 The Generator input mode is intended to accept irregular or unfiltered AC sources and is more likely to do so
than other modes. Since it will transfer the irregular power to the output as noted above, this should be
considered before using this mode with sensitive loads. (See page 9.)
In a stacked system, slaves are ordered to transfer at the same time as the master. If a slave does not
sense an AC source at the same time as the master, it will continue inverting, and will experience a
Phase Loss error (see page 40). This appears as an Event on the MATE3 system display, as described
in the MATE3 Owner’s Manual.
Offset
This function is designed to use excess battery energy to power the loads, even when an AC source is
present. This allows the system to take advantage of renewable energy sources, in effect “offsetting”
dependence on the AC source.
When a renewable source of energy raises the batteries above a designated reference point (or
“target”), the inverter exports power to the loads in order to bring the voltage back down or to
prevent it from rising further.
The inverter uses several set points as targets for the offset function, particularly the battery charger
settings. In the MATE3, the
Absorb Voltage, Float Voltage, and Equalize Voltage settings are all used
as reference voltages. While the battery charger is operating, it will regulate the voltage at a level
appropriate for the target setting.
If none of the battery charger’s timers are active, the target voltage used by the Radian inverter is
Sell Voltage in the Grid-Tie Sell menu. Unlike the other target voltages, the Radian inverter cannot
import AC power to raise the batteries to the
Sell Voltage set point. It can only use excess DC power,
if it is available, and export it as AC power.
(See page
Error! Bookmark not defined. for more information on how Offset relates to the battery
charger. See the MATE3 Owner’s Manual to change any of these settings.)
NOTES:
 If the Radian inverter is in the Grid Tied input mode and more renewable energy is available than can be
offset by the loads, the inverter will sell the remainder to the utility grid. Although the inverter can use the
Sell Voltage setting as a target in most input modes (see below), it is unable to sell power to the utility grid
unless the
Grid Tied mode is selected.
 If the inverter is in the Support, UPS, Backup, or Mini Grid input modes and more renewable energy is
available than can be offset by the loads, it means the inverter is capable of running all of its loads using
renewable energy. The inverter will disconnect from the AC source as long as the excess renewable energy
is present.
 The Offset function is not active when the Generator input mode is selected.