Selling a house with solar panels: One off solar PV system testing and inspection is particularly useful and often used by those selling or letting a house with solar panels installed. In addition to providing evidence that the system is working alongside up to date electrical test results, we'll make sure that all the documentation is in order, plugging any gaps and provide an easy to understand inspection report that will contain all of the information anyone might ever need to know about the solar PV system in one place, giving you, your buyers and their solicitors confidence in the solar PV system.

Buying a house with solar panels: If you instruct us as a buyer, as well as testing everything, making sure that the system is safe and that all the required paperwork is in place; we are always happy to spend time talking you through your new system, showing you how everything works, what to look out for, how to take meter readings and how to ensure that you get the most from your system.

Commercial, Industrial and Agricultural Buildings: Insurers of commercial, industrial and agricultral buildings will often ask to see evidence that the solar PV systems installed on them and or supplying them with electricity are regularly inspected, tested and maintained. We provide testing and inspection reports in accordance with IEC62446, that as well as confirming the ongoing safety and performance of these systems, can also be used to satisfy insurers.

• Equipment compliant with standards, correctly selected and not damaged
• Equipment accessible for operation, inspection and maintenance
• Equipment and accessories correctly connected
• Particular protective measures for special locations
• Equipment and protective measures appropriate to external influences
• System installed to prevent mutual detrimental influence
• Conductors correctly identified
• Conductors correctly selected for current carrying capacity and voltage drop
• Equipment and protective measures appropriate to external influences
• Conductors routed within safe zones and / or protected against mechanical damage
• Presence of fire barriers, seals and protection against thermal effects

• Ventilation provided behind the array to prevent overheating / fire risk
• Array frame & material corrosion proof
• Array frame correctly fixed and stable
• Panels in good condition, in working order and undamaged
• Roof fixings weatherproof
• Cable entry weatherproof

• Live parts insulated, protected by barrier, enclosure or class II
• Array frame equipotential bonding
• Surge protection correct and installed
• Additional protection by RCD

• Physical separation of AC and DC cables
• DC switch disconnector fitted (to IEC60364-712.536.2.2)
• DC cables correctly routed and protected with reinforced insulation
• All D.C. components rated for the system maximum (Voc and Isc x 1.25)
• PV String fuses or blocking diodes fitted

• AC isolators lockable in the ‘Off’ position
• Solar inverter correctly set and commissioned for local supply regulations

• General labelling of circuits correct
• PV System schematic displayed on site
• Protection settings & installer details displayed on site
• Emergency shut down procedure displayed on site
• AC and DC Isolators clearly labelled
• Signs and labels of a type suitable for the environment and correctly fixed

Once we have recorded this information, we then cross reference this against the data provided by the solar panel manufacturer and compare our data with how the solar panels should perform at standard test conditions.

Once differences in irradiance and temperature levels have been accounted for, we can then see if the solar panels are performing to the level that they should be. A solar panel or series of panels may test fine from a safety perspective but traditional testing and the basic safety testing carried out by solar inverters is not likely to help identify a poorly performing solar panel.

Given that most solar PV systems are wired together in strings and the performance of the string is determined by the weakest panel, 'safe' but unidentified poorly performing solar panels can have a big effect on overall power yields.

Environmental Degradation

Damage or corosion to cabling and connectors can decrease performance and increase the risk of fire. Solar panels can become dirty or contaminated over time and this can reduce their operational efficiency. Objects dropped by birds can result in physical damage to solar PV panels, which may also result in reduced output performance.

Regular electrical tests and inspections ensure that any damage or reduction in performance due to environental factors are discovered so that remedial action can be taken.

Damage to Wiring

Unprotected cables hanging below solar panels, touching roofs, bending around corners, chewed by rodents or rubbing against masonary can become damaged, presenting a shock hazard.

The insulated coating on the cables can degrade and expose bare wires. As well as allowing moisture to penetrate, this could also present a serious shock or fire hazard. Deterioration of cable connections and wiring can't usually be seen but they can be easily identified by applying regular electrical testing to identify potential faults.

Effective grounding

Solar panels and their mounting systems sometimes need to be grounded to mitigate potential electric shocks and fire hazards. If the grounding system degrades over time, anyone who comes into contact with a metal piece of the system may receive a shock. Should this occur, the chance of substantial injury is great because of the high voltages present and the potential danger of falling from height.

Ground faults

Poor levels of insulation in cables can allow energy generated by the PV system to leak to earth. This can be particularly problematic during damp or wet conditions where the insulation monitoring function within a solar inverter or external RCD prevents the solar inverter from starting up, which in turn can significantly reduce the operational efficiency of the PV installation.

Avoiding fire risks

As the number of rooftop solar installation systems have grown over the years, so have the number of reported incidents of fire. The periodic testing of the electrical cabling and components associated with solar power systems will ensure the safe operation of the system and reduce the potential fire risk associated with any electrical faults.

Compliance with IEC 62446

IEC 62446 recommends that periodic verification of an existing installation shall be performed. The standard defines the minimum requirements for system documentation, commissioning tests and inspection for solar power systems.

A periodic verification report should be provided and include a list of any faults and recommendations for repairs or improvements.

Verification of system performance

The value of a solar power system is linked to it's performance. Verification of system performance is essential to ensure that systems are returning on their investment in terms of power gain, carbon savings and realising FIT returns.

Simple electrical faults or wiring failures can cause a serious inefficiency in the ability of the system to produce power. Periodic electrical testing is vital to verify ongoing functional performance over extended periods.

Warranty & insurance fulfilment

Periodic electrical testing of solar PV systems to identify and confirm continued safe operation can be required as part of an equipment warranty or insurance claim.

A whole house surge protector is installed to provide protection from transient overvoltages originating from the mains/grid. A whole house surge protector is installed directly inline and as close as possible to the mains/supply meter, this allows for surge protection for all circuits and equipment including solar inverters, routers, stereos and other sensitive electrical equipment within the network. The addition of a 100Amp lockable isolator also allows for safe and convenient isolation of all electrical equipment within the network including consumer units, solar inverters, battery storage units and EV chargers from the mains/grid in one place.

Surge protectors are in compliance with the recently updated 18th edition amendment 2 of BS7671.

DC surge protection devices (SPDs) are installed between the solar panels and the solar inverter to protect both the solar inverter and the downstream electrical equipment from transient overvoltages of an atmospheric origin impacting the electrical system via the DC side of the system / the solar panels.

DC Surge protectors are in compliance with the recently updated 18th edition amendment 2 of BS7671.

Deliveries to anywhere in the UK are quick, tracked and accurate, technical support (by phone and on site if needed) and design/product advice is available before, during and after installation. The recording and collating of serial numbers, factory and other test results, manuals any other information required for equipment warranties, add ons and extensions is included.

Trade, DIY and Retail Clients Welcome.

Solar PV, Safety & The Building Regulations

Residential PV systems notifiable under Part P. Special consideration needed for Part A. A combination of serious risks for solar PV installers.

BSI - PAS 63100:2024 - Protection Against Fire of Battery Energy Storage Systems for use in Dwellings

This Publically Available Specification (PAS) from the British Standards Institution (BSI) was sponsored by The Department for Energy Security and Net Zero. Although not yet a British Standard, this guidance was developed in response to an urgent demand for clarity as to good practice across the industry including product, service and process standards.

Ground Faults, Isolation (ISO) Faults, RISO Low Faults and Insulation Resistance Faults with Solar PV Systems

After a number of years exposed to wind, rain, snow, ice and sometimes animals; solar panel systems can start to develop faults. The most common faults we find related to exposure are ground faults, isolation (ISO) faults, RISO low faults and insulation resistance faults. In this article we take a look at what these faults are, the possible causes and what steps are taken to identify and resolve them.