Outback Power Systems Systems manual Parallel Stacking More power at same output voltage

Stacking

At OutBack, we adhere to a philosophy that a power system should be fully customizable to address your specific needs. Therefore we set out to create the world’s only group of inverter/chargers that use a truly modular architecture. This modular architecture uses the next generation of a technique referred to as “stacking” to enable you to tailor your system for higher output power, increased charging capabilities and/or three-phase power configuration.

Whether stacked in parallel, classic series, series/parallel or three-phase there is always an inverter/charger which performs the task of Master. The Master talks to the other units through the HUB system communications manager while performing three major roles, keeping all inverter/chargers properly phased, controlling inverter and charger output levels, as well as putting unused inverters into Power Save mode to improve efficiency at low AC load levels.

Parallel Stacking - More power at same output voltage

When the inverter/chargers are stacked in parallel all inverter and charger outputs are combined. This means that each inverters AC output is added up to equal your total system AC output, up to 36,000 watts, in phase at the same 120 VAC/60 Hz or 230 VAC/50 Hz output voltage. Charging output amperage is also combined in this same manner.

			Load
			9 kW
3 kW 120 VAC	3 kW 120 VAC	3 kW 120 VAC	120 VAC

Classic Series Stacking - More power at higher output voltage

Stacking inverter/chargers in classic series provides a system with split phase 120/240VAC. This method does not allow balancing between separate legs on a system and is can only be used in dual inverter/charger systems without the X-240 Auto Transformer.

		Load
	3 kW		6 kW
3 kW 120 VAC	120 VAC
			240 VAC
	Leg 1	or
			Leg 1
	3 kW
			and
3 kW 120 VAC	120 VAC		Leg 2
	Leg 2

OutBack Series/Parallel Stacking - More power at all output voltages

Series/Parallel stacking or OutBack (OB) stacking is unique to OutBack inverter/chargers. Never before has it been possible to have inverter/char- gers balancing loads intelligently between two legs of AC power while seamlessly changing between series and parallel. OB Stacking uses the X-240 auto transformer to balance the loads between the two separate series legs of a system. The X-240 allows AC loads on leg 1 and leg 2 to be powered by any combination of inverter/chargers within your system. Even if there are only two inverter/chargers, connected in series, they can also func- tion as if connected in parallel. This allows larger AC loads to be operated by a system without risking overloading one of the 120 VAC outputs.

					Load
				9 kW		12 kW
3 kW 120 VAC	3 kW 120 VAC			120 VAC
						240 VAC
				Leg 1
					or	Leg 1
				9 kW
						and
3 kW 120 VAC	3	C	X-240	120 VAC		Leg 2
				Leg 2

3-Phase Stacking - More power for three-phase loads

Three inverter/chargers can be configured to provide 120/208 VAC or 230/400VAC four wire “Wye/Star” three-phase AC Power. An inverter/ charger is used to power each of the three legs for 3-phase AC power. The loads on each of the inverters does not need to be kept balanced, each phase is independently voltage regulated.

		Load
	3 kW
3 kW 120 VAC	120 VAC		9 kW
	3 kW	or
			208 VAC
	120 VAC
			3-Phase
3 kW 120 VAC	3 kW
	120 VAC
2005	OutBack Power Systems Inc. l 2811