Connecting the DC Wiring

DC Wiring for Multiple Inverters

For installations with multiple GT Inverters, separate solar arrays are required for each unit. The output of each GT Inverter feeds a separate dual-pole 30-amp circuit breaker (L1 and L2) in the main utility service panel.

For such installations, complete the wiring and perform the commissioning procedure for each inverter one at a time. For the commissioning procedure, see “Commissioning Multiple Inverters” on page 4–3.

WARNING: Shock hazard and equipment failure

Ensure each inverter is correctly connected to its own PV array(s) and that no wires are crossed. If inverters “share” more than one PV array, an input current difference of over 1 A between arrays can cause each inverter to fail—the ground fault protection fuse will blow, followed by short circuit failure. This failure will also generate hazardous voltages at the DC/AC disconnect switch on each unit.

For example, connect PV1 positive (+) and PV1 negative (–) to inverter 1 and PV2 positive (+) and PV2 negative (–) to inverter 2.

Do not connect PV1 positive (+) and PV2 negative (–) to inverter 1 and PV2 positive (+) and PV1 negative (–) to inverter 2. See Figure 3-6.

+

–

PV Array #1 (PV1)

+

–

PV Array #2 (PV2)

Grid Tie Solar Inverter

Grid Tie Solar Inverter

GT Inverter #1

GT Inverter #2

Grounding not shown.

Figure 3-8Improper Multiple Inverter Connections

975-0320-01-01

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