Hello Nigel,
Electrical enclosures for outdoor applications in coastal areas are exposed to particularly harsh environmental conditions. Therefore, special attention should be given to material specifications.
As with other solutions installed outside, your enclosure will likely be exposed to dirt, water and humidity as well as sunlight and UV rays. In addition, your enclosure will need to withstand a corroding, salt laden atmosphere.
In these situations, I strongly recommend you favour plastic-based solutions to metallic boxes or components, including screws, to maximise the equipment’s service life. For your outdoor application, materials such as polycarbonate (PC) and glass reinforced plastic (GRP) are ideal, as they are UV resistant and can withstand extreme temperatures as well as sudden changes.
In addition, you may want to look at enclosures that carry a 4X rating in accordance with the U.S. National Electrical Manufacturers Association (NEMA). NEMA 4X rated solutions are built to withstand two hundred hours of salt spray with minimal evidence of corrosive pitting, therefore, they can ensure optimal corrosion resistance.
NEMA 4X protection class corresponds to ingress protection (IP) 66 rating. You can find an overview on what enclosures are recommended for different environmental conditions as well as a comparison of NEMA and IP codes here: https://www.spelsberg.co.uk/service/technical-information/technical-information/assembly-and-installation-notes/
In addition, you should ensure that the fixing method you choose does not compromise the IP rating of your enclosure. To do so, it’s important to specify the correct number of entries needed as well as select a suitable fixing method, e.g. using internal fixing positions.
Spelsberg’s TK and TG series of PC and GRP-based enclosures and accessories feature optimal resistance against sunlight, dirt, water and chlorine-laden air to protect your electrical equipment in marine, coastal and offshore areas. You can use our ‘Product Finder’ to find a system that satisfy your requirements: https://www.spelsberg.co.uk/product-finder/
If off-the-shelf enclosures and fastening systems do not fully address the specific needs of your intended application, Spelsberg is able to support you by designing and delivering fully customised solutions. You can learn more about our capabilities here: https://www.spelsberg.co.uk/customising/
If you have additional specific requirements or need a bespoke solution, please feel free to send me a private message to discuss the specific requirements your enclosure needs to meet.