How can a double insulated light be made of metal?

How can a double insulated light be made of metal?

A question that we come across from time to time is how can a class 2 double insulated light be made of metal? After all, a double insulated light is designed with safety in mind so why would metal be used in their construction as obviously metal conducts electricity! Without the safety of an earth connection, a metal product clearly can become highly dangerous. It is not only customers that ask us this but also some electricians as well.

The answer is hidden in the nature of the construction of the product. A double insulated light is always designed in a manner so that any wiring at all that enters the unit is fully protected should an issue occur. The actual term double insulated originated from the doubling of the outer material protecting the light fittings internal wiring but modern manufacturers have gone way past this with additional features such as fully insulated and sealed connector housings. Lighting designers & manufacturers use a ‘plan for the worst’ scenario when creating a class 2 light. This is also the approach taken by the regulators and law makers who determine what is acceptable and what is not. This is why double insulated lighting is consistently mentioned in each new version of the current electrical regulations that electricians follow.

Double insulated lights are designed with special wire connection housings  that protect any potentially loose cables from touching the actual product

With a ‘worst case scenario’ being the breaking or working loose of an internal wire and touching the housing of a light fitting, rendering it live (and potentially deadly) a double insulated light must demonstrate how if such an occurrence happened inside itself, the relevant safety features would deter any problems for the owner of the product. This is one of the aspects that a double insulated light must pass when being tested before it is given a safety certificate & approved for general sale.

With these safety features & the thorough testing that occurs before a product is available it allows manufacturers to make a double insulated light fitting out of whatever material is suitable. As most light fittings are metal in construction and appearance and the fact that nobody wants their light to look unusual or stand out, then this is the material of choice for manufacturers & customers alike.

Approximately 95% of all double insulated lights are made of metal

In the past, lighting that was to be fitted in to homes without an earth connection would often be plastic (for obvious reasons) however this was before the lighting and electrical industries took note and started to regulate the use of specialist class 2 products leaving us in a much safer place where regulated, tested & approved products now are available where as in the past a non-regulated, ‘do what you want’ approach was taken.

If an electrician tells you that you shouldn’t be using metal light fittings where an earth isn’t present, he is only using his extensive knowledge & obvious care for his client. They should however rest assured that a properly regulated & tested area of the lighting industry exists for such occurrences & works day in day out with experienced professional electricians up & down the country. A refresh of the latest ‘electrical regs’ would also confirm this for them.

The square within a square symbol on a lights manufacturer label  reassures  both the owner & the electrician that the fitting is suitable for an installation without an earth

Although double insulated lighting is the answer, you are in a far more comfortable situation if your electrician is unsure and researches it (if they happen to not have heard of class 2 lighting) than an electrician that justs wants to put up whatever & move on to the next job, which we have heard about from time to time. To sum up, if you don’t have an earth connection and you need lighting then the 2 most important things you need are double insulated lights & a good electrician who knows of class 2 products or is prepared to research them for you.