PV Overview

PV Array

PV Modules were assembled in trio, prewired and lifted in place by hand.

The modules are SunWize 120Watt modules. A total of 21 modules will complete the array for a total array capacity of 2520 Watts peak.

These modules are all connected in series to create a single array.

The first step to assemble the PV array was to bolt the PV modules to the mounting rails, 3 at a time. Each 3-module panel weighs about 100 lbs.

All connections were assembled finger tight at first; then we squared by measuring diagonals, then tightened. Once tightened, Locktite (shown at left) was used to prevent the bolt-nut-lockwasher assemblies from coming loose.

Dulci and Carl prewire the PV modules. This eliminated the need for wiring on the roof.

Module interconnects between the 3 modules were run in outdoor rated non-metallic conduit, called flex. THHN wires were run in the conduit between junction boxes. At the left is the quickconnect module interconnect wire available from Sunwize. It is a #10 AWG single stranded wire, rated USE-2. This means it is rated for outdoor use with resistance to sunlight and a 90C temperature rating. It is the only type of wire commonly available which is suitable to be run as exposed single cable between PV modules.

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Jeff and Dulci are checking the Open Circuit voltage and Short Circuit current of each module and the trio assembly. At least two of the modules seemed a bit low in voltage and may have been at or below the low end of the the specified voltage window.

This may not be significant given that the entire array is a wired in series and is run through the Sunny Boy Inverter which is equipped with Maximum Power Point Tracking.

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