Photovoltaic Solar Generator Systems need Surge Protection

Rooftop photovoltaic solar generators mostly consists of a metal frame that all the panels are screwed down, with all the cables and plugs fitted underneath them. This can make your roof very susceptible to a lightning strike and damage to your property and equipment.

This is why all rooftop solar generators should be fitted with some kind of Surge & Lightning Protection. LPS (Lightning Protection Systems) as in a lightning rod and earthing tape down the side of the property will help, but SPDÂ’s (Surge Protection Devices) should always be part of a professionally designed and installed photovoltaic solar installation. Some insurance companies will insist on you having this installed or may even drop your policy pricing if it is fitted. (Always check this with your insurance company)

With the new 18th Edition Wire Regulations changes for Lightning and Surge Protection, Section 443 states;

Protection against transient over-voltages SHALL be provided where the consequence caused by over-voltage could:

result in serious injury to or loss of human life, result in interruption of public services and or damage to cultural heritage, result in interruption of commercial or industrial activity or affect a large number of co-located individuals.

So for public and commercial buildings, lightning protection will be used in pretty much all cases.

For all other installations a risk assessment should be carried out using the calculation method listed in BS7671:2018, except for single dwelling units where the total value of the installation and equipment therein does not justify such protection.

NB – if no risk assessment is carried out – Surge Protection measures SHALL be provided.

Resultant figure from Risk Assessment –

Less than 1000 – Surge Protection measures SHALL be provided

Greater than 1000 – No Surge Protection is required

The installation of SPDÂ’s should then be carried out in accordance with Section 534 of BS7671:2018

Also remember that surges are not just coming in from your roof via photovoltaic solar generators they can come in from TV Aerials, Satellite Dishes, CB/ RF Radio Aerials, Telephone Lines, Internet Cables, Metal Piping, Gas, Water and any Underground Electric Cables entering the property. All of these could be at potential risk from surge spikes entering if there is a lightning strike in the vicinity of your property.

If a surge enters the wiring system via any means it could be a very costly problem. The spike of power from the lightning could cause a power surge through the main income supply line of the house to the main fuse distribution board and spread throughout the whole houseÂ’s wiring circuit, ring mains, spurs and lighting. This could damage all appliances connected to plug sockets, unprotected extension leads, etc. in the house.

We always believe that you should take a coordinated approach when choosing surge protection. For more info see downloadable PDFS below.