5 safety tips for photovoltaic systems
The current photovoltaic energy market offers a wide variety of options and prices for consumers. However, neither the cheapest nor the most expensive is necessarily the best. Customers must demand high quality equipments with high quality installation. One of the most important things that should not be sacrificed is the electrical safety. The installation must comply with national and international safety standards. In this blog we share 5 safety tips for photovoltaic systems and what you should ask your supplier before purchasing it.
Equipment must have manufacturer’s certification
It’s important to verify that the equipment to be installed (solar panels, inverters, batteries) is new, factory certified and of world-renowned brands that have support and guarantees. You should also verify that materials such as cables, charging stations, pipelines, among others, are also certified.
National Electric Code must be respected during installation
Safety standards are something that never stop evolving and updating. In 2019, Costa Rica updated the Costa Rica’s Electric Code for the Safety of Life and Properties, which today refers to the NEC2014 (United States National Electrical Code). This is a best practice reference to protect the electrical safety of people and properties. However, it does not include design specifications or a users guideline. This criteria is reserved for responsible engineers that supervise and approve photovoltaic designs. In Costa Rica, The Engineers and Architects Federal College is the entity that regulates the compliance of the code mentioned. Also, the Distributed Generation Chamber has a Best Installation Practices Code, which all members must comply with. At greenenergy® we are an active member of this Chamber.
System must include a Rapid Shutdown
One of the most important changes that impact photovoltaic projects is the Article 690.12. It refers to the “Rapid Shutdown for photovoltaic systems in buildings”. This refers to the use of special equipment that rapidly disconnects the system. The code indicates that it is a requirement for controlled conductors to be applied to PV system conductors longer than 1.5m inside a building, or to those longer than 3m from a PV array. These quick disconnection devices are certified for this application and allow the disconnection of direct current sections, improving the electrical safety of the systems.
This clause, which has been modified in later versions of the NEC, has allowed a large number of PV project developers to install inverters on rooftops, solely and exclusively to avoid installing this “rapid shutdown” protection mechanism and thus reduce project costs. Sacrificing compliance with safety standards in a PV project can reduce costs from 2% – 4%, depending on the type and complexity of the project. However, long-term damage can be much more costly.
While it is true that many brands of PV inverters are certified to be used outdoors and operate in the heat of the day, they tend to decrease their efficiency and lifetime under these conditions. From our perspective, this is not recommended for the investments of any interested consumer.
This article is later replaced in the NEC2017 (not approved in Costa Rica) by 30cm conductors, and later in the NEC2020 (not approved in Costa Rica) where compliance is requested at the level of photovoltaic modules. This shows how safety is always evolving to improve and this should always be the design criteria of any electromechanical project.
Verify compliance of safety aspects
The gaps that the National Electric Code has, allows a lot of different interpretations from the photovoltaic companies. It is important that the customer trusts the supplier and feels secure about the investment. These are some safety aspects that are sometimes sacrified in PV projects to make them cheaper, and that as a consumer, you should double check:
- Certified cables
- Specifications and certifications of circuit breakers
- Choice of unsuitable transformer equipments
- Grounding electrical systems
- Inadequate interconnection and protection equipment
- Engineering studies to evaluate the performance of the new electrical system
- Choice of conduit and its material
- Rapid shutdown equipment (as mentioned on tip #3)
Minimize risks and dangers
There are many risks and dangers in case safety standards are not followed in a PV installation. For example, there may be electric failures that put the equipments, site, or safety of the people in the building at risk.
Our final tip: ask for a meeting session with the Engineering Department before purchasing a system
At greenenergy® we recommend you ask for a meeting session with the Engineering Department. This should be done before choosing the company that will install your PV system. During this sessions they must share the components that will be used, why they were chosen, and request approval of all components to be installed. Finally, work with expert advisors who can recommend best installation practices from the start. If you want to know more safety tips for photovoltaic systems, contact us!