- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 28 Nov 2017
DC isolators for photovoltaic systems (FB 68)
On 7 October 2014, BRE published DC isolators for photovoltaic systems (FB 68), by Steve Pester.
Photovoltaic (PV) power systems are becoming increasingly commonplace. But rapid expansion of the market brings with it a need to be vigilant in the maintenance of standards. Misunderstanding the details of the technology can prove dangerous.
DC isolators are a critical component for the safe design and installation of PV systems, and were made mandatory by the Wiring Regulations (BS 7671). But a lack of understanding has led to a few incidents of fire in UK installations. In most cases they are safe and reliable, but if they are incorrectly specified or installed isolators can cause fires. This 28 page guide explains the key points that should be taken into account when specifying DC isolators, including the standards and certifications required.
The guide describes the purpose, functions and features of isolators on PV systems as well as some of the available products. It explains some of the issues found in the field, with a rogues’ gallery of examples and reviews the relevant standards and guidance currently available
The contents of the guide include:
- What is an isolator?
- Current issues and rogues’ gallery.
- AC and DC electricity.
- Typical PV systems.
- Types of DC isolator on the market.
- Specifying DC isolators for PV systems.
- Standards and certifications.
- Conclusions and recommendations.
- Appendix: Utilisation categories.
- References and further reading.
 Find out more
 Related articles on Designing Buildings Wiki
- Battery energy storage systems with grid-connected solar photovoltaics BR 514.
- BRE articles on Designing Buildings Wiki.
- BRE Buzz articles on Designing Buildings Wiki.
- BRE National Solar Centre.
- BRE photovoltaic certification scheme.
- Building Research Establishment.
- Code of practice for grid connected solar photovoltaic systems.
- Future of electricity in domestic buildings.
- Large scale solar thermal energy.
- PV inverter.
- Solar photovoltaics.
- Solar thermal systems.
- The Future of Electricity in Domestic Buildings.
Featured articles and news
How it can benefit construction.
Free guide to commissioning for site managers published by NHBC and BSRIA.
Resolving quickly to minimise delay and costs.
Tackling domestic abuse.
Disallowed costs vs. defined costs. Which is which?
Coping with the loss of local authority conservation services.
Remedial works could save the NHS £95 million a year.
One of Europe’s largest waterfront transformations.
How BIM was used to produce an information model of a home.
Skyscrapers of the future will be built of wood.
How to increase your chances of winning.