Snag: Electrical enclosures, such as junction boxes and luminaires, located outdoors are susceptible to water entry. A Common defect observed in equipment located outdoors is the entry of Water. In almost all cases, water entry into electrical equipment will cause corrosion of metallic parts and water allowed to accumulate inside equipment will result in an electrical fault.
The Solution from the NICEIC
The likelihood of water penetration must be carefully assessed.The customer should be consulted upon the utilisation of equipment that might influence the assessment. The full performance details of equipment must be written into the specification or summarised on any quotation. Equipment must be specified and selected with a suitable IP (International Protection) rating to be suitable for the external influences and erected in accordance with the manufacturer's instructions. Solid foreign objects and water are both external influences, an assessment of which must be carried out for each installation (Regulation 300-01-01 refers) ............
The document attached below in PDF format provides a full answer to this common problem and is clearly illustrated with diagrams and tables. Click on 'Downloadable attachment(s)' below to find the full answer from the NICEIC.
A short slide show below will give you an ideal of the images and tables contained in the answer.
This is just one of the 50 Snags in Snags & Solutions (A Practical Guide to Everyday Electrical Problems - Part 2 Wiring Systems) published by the NICEIC. To buy you own copy of this invaluable reference book, click here.