Xantrex Technology power Inverter Stacking manual DC Wiring

Installation

DC Wiring

The success of series-stacked, inverter systems is dependent on the quality and maintenance of the DC connections. Stacked inverter sets are far less forgiving to long, undersized, uneven, and/or poor connections than are single inverters.

Battery Requirements for Series-stacked Inverters

When inverters are “stacked” they must operate from a common battery bank. In other words, the DC negative of one inverter must be common with the second inverter and likewise for the DC positive.

For example:

If you have eight 6-volt batteries in a 24-volt configuration, they would be arranged in two rows of four batteries (see Appendix C of the Sine Wave Plus Owner’s Manual for diagrams of various arrangements). The negative ends of the two “strings” of batteries must be jumpered together to become common with each other. Likewise, the positive ends of the two “strings” must also be jumpered together so that they are also common with each other.

Battery-Bank Configuration for Series-stacked Inverters

When using inverters in a stacked configuration, the same battery bank must be used for both inverters. To ensure even charging of the batteries, each inverter must be connected to both strings (i.e., positive cable to string two, and negative cable to string one for inverter 1, and positive cable to string one and negative cable to string two for inverter 2) as shown in Figure 2-1. In other words, a separate positive (+) and negative (–) cable pair is required for each inverter in the series-stacked configuration. This means there will be four battery cables from the stacked inverters to the battery bank.

Refer to the Owner’s Manual for the Sine Wave Plus to determine the correct size and length of cable required.

DC conduit for	DC conduit for
L2 Inverter	L1 Inverter

–	+	–	+	Series String 1
	12 Volt	12 Volt		24 Vdc/200 Ah
		Battery
Series-strings	Battery
		200 Ah
wired in Parallel	200 Ah
24 Vdc/400 Ah
				Series String 2
–	+	–	+	24 Vdc/200 Ah
	12 Volt	12 Volt
	Battery	Battery
	200 Ah	200 Ah

Figure 2-1Example of Battery Connections for Series-stacked Inverters (24 Vdc shown)

2–2 975-0059-01-01 Rev A