Solar System Components

Solar System Components – Balance of System (BOS)

Solar systems consist of more than solar panels, batteries, and inverters. Surge protection, safety disconnects, labeling, and grounding are all essential solar system components.

There is an endless list of system components you can incorporate into your renewable energy system; don’t hesitate to get in touch with us if you can’t find what you are looking for.


Every day, solar photovoltaic installers struggle with correctly marking their installations in a way that is practical to implement and that meets the expectations of inspectors. The labels in this section comply with NEC requirements, are easy to attach, are durable, and resistant to sunlight for years.

Surge Protection

A lightning arrester is a device used on electrical power systems to protect the circuit and the insulation in case of an unexpected surge in the voltage. Lightning Arresters can also be found as Surge Protectors or Surge Arrester. The typical lightning arrester has a high voltage terminal and a ground terminal. When a lightning or a high voltage surge travels down the power system to the arrester, the current from the surge is diverted around the protected insulation, in most cases to earth.


The proper methodology for grounding solar arrays and solar systems is dictated by the National Electric Code (NEC). As an extension of the NEC, every equipment manufacturer, especially PV module makers, have their suggestions for grounding their PV modules. Manufacturer’s suggested grounding practices must always comply with the NEC and UL article 1703.

Even though all electrical equipment in a solar photovoltaic system must be properly grounded, including inverters, racking, and electrical boxes, PV modules are inspectors’ main grounding safety concern. Grounding lay-in lugs have been extensively used for grounding PV modules; now, grounding lay-in lugs are being replaced by grounding clips, which eliminates screwing the set screw by clipping the cable. There is also stainless steel grounding bolts for solar systems installed in corrosive environments.

Another grounding practice that has gained a lot of momentum is grounding washers, commonly called WEEBs, which eliminate screwing lugs or clips to individual modules altogether. By piercing the solar modules to the mounting rails, the WEEBs can properly ground an entire row of solar modules with only one lug, reducing labor and copper cable consumption considerably.

Combiner Boxes / Fuses / Breakers

A Combiner Box is an electrical distribution box where multiple series of solar PV modules are connected and combined in parallel into one DC output. Combiner boxes used in off-grid systems generally use DC rated breakers. Combiner boxes used in Grid-tie solar applications use 600VDC rated fuses. Please note that fuses, breakers, and in some cases fuse holders need to be purchased separately.

To choose the correct combiner box, it is necessary to determine the number of strings of solar panels and the breaker or fuse size. A typical breaker size is 15 – 20 Amps.

Cables and Connectors

PV modules require special connectors for connections between the modules and other devices. In this section, we display the connectors that PV module manufacturers widely use. We also include a selection of heavy-duty cables for battery interconnection. PV Cable will be required in a particular type of application, especially in larger PV systems.