Magnum Energy Series Stacking Cable Kit (ME-SSI) - Manual (Page 23)

©
2010 Magnum Energy, Inc.
Operation
18
Inverter Operation
Invert Mode - The units are turned on by pressing the Power ON/
OFF switch on either inverter. Alternatively, they can also be start-
ed by pressing the INVERTER ON/OFF button on a remote control
connected to either inverter. When the two inverters are inverting,
they communicate over the Stacker cable. This cable communi-
cates to monitor the AC output from each inverter and shift it 180°
out of phase from each other to provide 240VAC on both units,
and to verify that there are no faults on either unit to prevent only
one unit from inverting. The two units also use the DC negatives
as a reference point while they are communicating; hence, the
reason why the DC negatives must be tied together – to ensure
there is no negative voltage difference between the two units.
Inverter settings - When the units are inverting as a series
stacked confi guration, certain settings must be coordinated in each
unit for proper operation. Without a remote control, the default
settings on each unit will be coordinated. If using a remote con-
trol, check that the following settings are the same between the
two units:
1. Ensure the Adj LowBatCutOut setting is the same for both units.
2. If the Search mode is needed, then set the Adj Search Watts
setting for each inverter to determine when to start powering
120VAC loads. The two inverters are independent, which means
one inverter can come out of Search mode and start inverting,
while the other unit continues in the Search mode until a load ex-
ceeds the search watts threshold of that unit. If powering 240VAC
loads, then the search watts sensibility is determined by combining
the ‘Search Watts’ setting on both units.
For example: Given a 15 watt Search Watts setting on the L1
inverter and a 10 watt Search Watts setting on the L2 inverter,
and a 20 watt/120VAC load on the L1 inverter and no load on the
L2 inverter. This would cause the L1 inverter to start inverting, but
the L2 inverter would continue in Search mode. With the same
Search Watts settings, a 25 watt/240VAC or greater load would
cause both the L1 and L2 inverters to come on and start inverting.
Charger Operation
Charge Mode – The series stacked confi guration is designed to
accept 120VAC to each inverter, typically from a split-phase, 3 wire
120/240VAC power source. The HOT IN terminals of each inverter
accepts one line of 120VAC each and the NEUT IN terminals of
both inverters are tied together and connected to the AC power
source neutral line. When the AC line voltage and frequency are
good to both units, they both transfer and go to Charge mode and
begin charging – if enabled. However, it is not necessary for either
unit to have charging enabled for the pair to operate.