Westinghouse AC System, Installation Manual

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Westinghouse Solar AC Installation Guide
Copyright © 2011 - Westinghouse Solar 14 | P a g e
Section III. Creating an Electrical Diagram
It is important to understand the electrical design principles specific to Westinghouse Solar technology
before you begin your electric line diagram. Sample designs for 15 panels (or fewer), 30 panels and 45
panels are provided in an Appendix. Below are some important concepts to consider as you create
your roof layout and electric line diagrams:
1. Westinghouse Solar AC Electrical Requirements
A. Westinghouse Solar AC Panels may be arranged in branch circuits of up to 15 when working
with 240V single phase electrical systems. Each branch circuit will need to be isolated using
NEC compliant circuit protection
B. When Westinghouse Solar AC panels are arranged on a roof layout, they are wired in parallel,
and invert DC power on a per panel basis. For this reason, panels can be placed on roofs of
varying pitches, orientations, and shading scenarios. Their performance will not be hindered
by adjacent panels in the same branch circuit
.
C. Westinghouse Solar AC branch circuits require three proprietary components to complete a
multi row branch circuit. An AC branch circuit is ended with an “end cap,” which is a plastic
fitting that protects the last inverter in a circuit from moisture and exterior elements. Because
the wiring harnesses come built into the inverters at a preset length, a 6' extension cable is
necessary to wire branch circuits in the north /south direction, and also to route the inverters
past obstructions (such as a vent pipe). Finally, Westinghouse Solar AC circuits are completed
with a “Pigtail” connector; the Pigtail transitions the inverter's conductors from the UV rated
insulation to four color-coded conductors that can be utilized inside a junction box on the
edge of an array. Each Westinghouse Solar AC kit includes one Pigtail and one end cap.
D. Inverters mounted on Westinghouse Solar AC panels work most conveniently when the wiring
harnesses are aimed towards the junction box, or final destination for a circuit on a rooftop.
By carefully planning the direction and orientation of Westinghouse Solar AC Panels, your wire
management will be simplified and system will be installed with fewer extra components.
E. Westinghouse Solar AC inverters are attached to the panel frame using an UL-approved
bonding method. These attachments utilize thread-forming bolts in addition to star washers
to ensure a solid and redundant bonding path between the frame and inverter.