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SOLAR POWER SYSTEM DEPLOYMENT 131

the City of Hemet; several lecture halls, a bookstore, a cafeteria, and two auditoriums.
In this installation, PV panels were assembled on specially prefabricated sled-type
support structures that did not require roof penetration (Fig. 3.67). Roof-mounted PV
arrays were strapped together with connective ties to create large island platforms that
could withstand 120 mi/h winds. A group of three PV assemblies with an output power
capacity of about 6 kW was connected to a dedicated inverter. Each inverter assembly
on the support incorporated overcurrent protective circuitry, fusing, and power-collec-
tion bussing terminals.
The inverter chosen for this project includes all technology features, such as anti-
islanding, ac power isolation, and voltage and frequency synchronization required for
grid connectivity. In addition, the inverters are also equipped with a wireless monitor-
ing transmitter that can relay various performance and fault-monitoring parameters to
a centrally located data-acquisition system.
Strategically located ac subpanels installed on rooftops accumulate the aggregated
ac power output from the inverter. Outputs of subpanels, in turn, are cumulated by a
main ac collector panel, the output of which is connected to a central collector distri-
bution panel located within the vicinity of the main service switchgear. Grid connec-
tion of the central ac collector panel to the main service bus is accomplished by means
of a fused disconnect switch and a net meter. Figure 3.68 shows a nonpenetrating solar
power system.

Figure 3.67 Water and Life Museum rooftop solar power system. Photo courtesy of
Vector Delta Design Group, Inc.