How to Install Photovoltaic Systems in Pennsylvania

Determine if your home is a good candidate for installing a photovoltaic system. Homes should have maximum southern exposure with full sun from 9 a.m. to 3 p.m. during the day. However, your home can have a deviation of 30 degrees or less from true south and still be a good candidate for a photovoltaic system. For a roof-mounted photovoltaic system, the ideal roof slope is between 39 and 42 degrees in Pennsylvania, according to PA Solar. Roof slopes that are between 20 and 60 degrees are also acceptable. Also check the condition of your roof by consulting with a structural engineer. A roof should be able to support three pounds per square foot to hold a photovoltaic system.

Complete the paperwork for installing a photovoltaic system. The paperwork will vary depending on which municipality in which you live. Your municipality in Pennsylvania might enforce different codes than others when it comes to photovoltaic systems. Building and electric permits will need to be in hand before beginning the installation.

Choose an installation site for the photovoltaic system. The rafters in your home need to be identified, which will determine where the mounting rack for the photovoltaic system is placed. The rafters can be located by using a stud finder or examining the underside of your home's roof from the attic.

Install the mounting clips for the photovoltaic system into the roof by following the manufacturer's instructions. PA Solar recommends using a UV-resistant sealant around the mounting clips to avoid leaks in the roof. The mounting clips should be installed so that they allow for a 3- to 4-inch gap between the roof and the photovoltaic system.

Check all parts of the photovoltaic system for cracking or any other problems before hauling it up onto the roof. Depending on the system, you may be able to assemble some parts of the module on the ground. Check the open circuit voltage and current before placing the unit on the roof, as well. Use wire nuts or electrical tape to cover the ends of the wires on the module before lifting it onto the roof.

Lift the system onto the roof. This can be done by standing on a ladder and handing the photovoltaic system to another person on the roof or by creating a pulley system to haul the module up onto the roof. The size of your photovoltaic system will greatly affect how much help you need in installing it. A smaller system can be installed with just two people, while a large system will need a whole team of helpers.

Attach the photovoltaic system to the mounting clips on the roof according to the manufacturer's instructions. This is generally done by tightening downs screws and bolts. Check all mounting screws and bolts to ensure that the system is secure on the roof before you proceed with wiring the module.

Turn off the electric panel breaker and turn all switches off before connecting any wires. Attach the frame ground wires and all other wires in the appropriate junction and combiner boxes. Check the connections on all the wires and tighten them up if any are loose.

Flip the panel breaker back on. Use a voltmeter to check the open circuit voltage and polarity of the combiner box. If the current registers too high for the voltmeter to read, use a DC ammeter to determine the level. Label the breaker panels to identify the photovoltaic circuits.

Turn on the inverter. At this point, the photovoltaic system should start to produce power. If it does not, consult an electrician to assist you in troubleshooting the system.

Write an electric schematic of your photovoltaic system to show to the electrical inspector. Schedule your electric inspection and follow any instructions the electricians gives to ensure your photovoltaic system is up to code for your municipality in Pennsylvania.