Xantrex Technology STXR1500, STXR2500 Connecting Inverters in Parallel

Installation

PV ARRAY

EXTERNAL

COMBINER BOARD

– +

STXR UNIT

	SOV			BYPASS TERMINALS		PV COMBINER BOARD
						–	+ 20 A
				PV GROUND FAULT				+
A	LIGHTNING						–
				BREAKERS (OPTION)
	ARRESTOR
							20 A	+
	(OPTION)			100 A	100 A
15 A							–
L1	L1		+	+			20 A	+
15 A							–
L2	L2	INVERTER						+
							20 A
G	G		–	–			–
							20 A	+
				1 A
							–
							20 A	+

–

Main

Breakers

G

L2

	Sun-Tie	NEUTRAL
L1	Breakers
		GROUND

MAIN SERVICE PANEL

NOTES:

INSTALLER CONNECTIONS REQUIRED AT POINTS (A) AND (B) TO THE INVERTER ENCLOSURE.

THE UTILITY METER MAY BE A BI-DIRECTIONAL METER OR DUAL METERS MAY BE USED.

OBTAIN UTILITY COMPANY APPROVAL BEFORE INSTALLING.

			B	Extra Ground Rod
				Only Required on
				Long Runs > 100
L1	L2			feet (30 m).
		L1
UTILITY METER			UTILITY
		L2	GRID
		N
	N
				975-S00-003A

Figure 2-15 Simplified electrical wiring diagram (using PV bypass terminals)

Connecting Inverters in Parallel

Reasons and requirements

Connecting AC and DC wiring

Sun Tie XR inverters may be connected in a parallel configuration to harvest additional energy from the sun. In this configuration, a separate solar array is required for each Sun Tie XR unit. The output of each Sun Tie XR feeds a dual-pole 15-amp circuit breaker (L1 and L2) in the main utility breaker panel.

The procedure for wiring the additional Sun Tie XR is exactly the same as previously described for the AC and DC wiring. Additional Sun Tie XR inverters can be added in the future as required.

An example of a parallel configuration is shown in Figure 2-16.

Note: If you are combining two Sun Tie XR inverters into a single dual-pole breaker (30 amp, for example), you will need to size the AC wires and conduit to the larger breaker. If this breaker trips, it will also shut down both inverters. For these reasons, we do not recommend using a single dual-pole breaker.

975-0053-01-01 2–21