46
Freedom SW Installation Guide
Stacking Features
Stacking Cable
For series stacking (120 and 240 volts), connect the Xantrex stacking cable
between the two
STACKING
ports.
To order the stacking cable, call Xantrex and order part number 808-9005.
Theory of Series Stacking Operation
The inverter is designed to accept power input from a single-phase, three-
wire 120/240-volt AC system with 120 volts to each inverter. The input line
(
INPUT L
or
L1
) terminal of each inverter accepts one leg of 120 volts each
and the input neutral (
INPUT N
) terminals of both inverters are tied together
and connected to the power source neutral leg.
Any AC loads being powered while AC input is present to the inverters will
be in addition to the power being drawn for charging the batteries. Each unit
in the stack can provide a full pass-through current of 50 amps for 120-volt
systems.
When AC input power is lost, both units in the stack switch from charger to
inverter mode. Once this switch is made, 120 volts AC is available from
each individual inverter or 240 volts AC is available across the output line
(
OUTPUT L
or
L1
) terminals of the stacked pair.
Stacked inverters will typically support about twice the surge power of one
standalone unit. For example, a Freedom SW 3012 stacked pair will surge
about 12000 watts.
Figure 19
Stacking Cable for Series Stacking
CLEAR FAULT
RESET
INVERTER
ENABLED
Inverter
On
AC/
Charge
Fault
FREEDOM
SW
INVERTER/CHARGER
STACKING
XANBUS INTERFACE
CLEAR FAULT
RESET
INVERTER
ENABLED
Inverter
On
AC/
Charge
Fault
FREEDOM
SW
INVERTER/CHARGER
STACKING
XANBUS INTERFACE
Two Freedom SW 3012 units shown.
Freedom SW 3K2K InvChg Install Guide.book Page 46 Wednesday, October 12, 2011 4:40 PM