Small Scale Offgrid Solar PV: Installation Manual
Offgrid Solar Energy: Electrical generation with Solar Panels without connection to the
electrical grid. This needs at least one battery so that the energy can be used when there is no
sun. This Manual is relevant to installations of one single solar panel, or lower than 235W.
Isc Short-Circuit Current: The short-circuit current is the current across a solar cell when the
voltage is zero (or when the solar cell is in short-circuit.) Published in the technical data on the
underside of a panel, it‟s one of the main parameters of a Solar Module. Normally it‟s quoted
under Standard Test Conditions („STC‟); 1000 W/m solar irradiation; 25 °C cell temperature.
Solar Panel: A module that makes use of energy from solar irradiation. This guides refers to
Photovoltaic Panels to generate electricity
Regulator (Charge Controller): This balances the voltage of the Solar Panel, Battery and DC
Circuits, and monitors the State of Charge (SOC) of the battery. It protects the battery from
overcharging by the panel, and disconnects DC loads when voltage is low to prevent over-
discharge.
MC4 Terminals: Connecters for the DC solar cable. In general they are the industry standard.
VOC Open Circuit Voltage: Difference in Electrical Potential between two terminals of a device
when no external charge is connected. Under these conditions there is no external electrical
current between the terminals. Voc of a solar panel should be published in the technical plaque
on its underside. It is quoted according to Standard Test Conditions („STC‟.)
Tools
Compass; Volt-meter; Pliers; Ratchet crimping tool; Hammer; Screw-drivers; Fixed Spanners;
Wire Cutters; Spirit level; Tape measure; Marker pen; Stanley knife; Battery drill (with two
charged batteries); Hacksaw; drill bits including a 3/8” socket bit and a screw-driver bit;
ladder.
Material
The success of the installation depends on arriving prepared with the right kit.
Solar Panel; Charge Controller; Inverter; Battery
Cable for different parts of the installation; Cable clips; MC4 Connectors (Solar Cable)
Hexagonal roof screws - 3 ½“ and other sizes; 4” nails
Threaded hexagonal bolts - 5/16 x 11/2". 5/16” nuts and washers. Silicone.
Angle aluminium 50mm x 50mm x 2.5mm (3m.) Wooden board (around 30cm x 3cm x 160cm.)
Crimp connectors (for batteries); Crimp connectors (for splicing); Light bulb sockets; Switches;
Energy saving 12V bulbs
Self tapping screws; wall plugs; Cable ties; Red and black electrical tape.
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