On Sat, 3 Feb 2018 03:59:42 -0800 (PST), wrote:

On Saturday, 3 February 2018 11:14:03 UTC, Archibald Tarquin Blenkinsopp wrote:
On Sat, 3 Feb 2018 02:15:07 -0800 (PST), tabbypurr wrote:
On Friday, 2 February 2018 20:52:01 UTC, Archibald Tarquin Blenkinsopp wrote:

Why should he change?

I can go to Asda tonight and buy a mains lamp that in all honesty look
far less safe than those in the photo.

to avoid the risk of expensive legal proceedings

The wall wart may be a good idea but are you aware that the light
still needs PAT testing if testing is required?

AB

If the light were powered from a SELV wallwart, only the wallawart would need PAT testing - at times when a PAT test is warranted that is. Which it isn't anyway. But with an external wallwart the safety requirements for the ELV luminaire become lower & easier to achieve.

For arguments sake, you remove the mains lamp from the box and insert
one lamp and PSU.

How do you gain?

I'm not recommending it, but you gain by the luminaire being exempt from the rules & regulations that apply to mains appliances. It's why wallwarts are so popular.

If the client demands a PAT test on the lamp, it's unlikely that he'll
allow the new version to go through also.

quite the opposite, wallwarts are trivial to pat test. A wallwart powered luminaire is exempt from PAT testing as it's not a mains electrical device. It would also be exempt from the need to be class I or II, for strain relief & so on.

A test is a test full stop. You plug a device into the mains, it's a
portable appliance. To argue that testing is somehow easier or less
stringent by adding a PSU is ridiculous.

AB

Then you need to brush up on your PAT testing knowledge. Laptops powered by a brick are PAT exempt, only the PSU needs testing.

And I can't see any way in which exempting the 19v laptop from PAT testing would be ridiculous. On the contrary it would be a bit ridiculous to PAT test it, as it's never connected to the mains.


NT
Let me make it simple for you.


A test is a test full stop. You plug a device into the mains, it's a
portable appliance.

There we are, I got rid of the confusing bits.


Is there anythin else you dont understand?

AB