Hello All,

I am planning to sell a lamp i designed myself. It contains a small LED pcb powered from 5v USB-A. I am currently reading up on all the standards to fugure out what kind of testing I need to do to comply with CE.

One thing I'm confused about is how much electrical protection should be build into the pcb / lamp itself. I of course plan to specify in the manual what the requirements are for the power supply (or potentially that it should only be used with the one I include). However I'm still unsure to what extend my board / lamp as a whole should be able to handle e.g. someone using a faulty adapter.

Lets say someone connects a USB adapter that has accidentally shorted and there by sends mains voltage to my board. Would this be considered a realistic scenario that I should account for? In terms of risk of fire / electrical shock / etc.

Any input is much appreciated!

Best regards,
Olav

 

If your spec says 5V±5%, it has to withstand that. If someone connects mains to it, either deliberately or inadvertently, then it’s their problem not yours.
The mains thing you have to pass would be EMC.
For safety, there must be no dangerous voltages touchable when connected to the correct power supply. So, unless you have a step-up converter delivering more than 60V you are OK.
Test to be done “under fault conditions” refer to faults within your product, not faults in the supply the someone might connect it to.

 

I suggest a series fuse, rated about 50% more than the lamp draws,soldered into the PCB with the other parts.And the caution note"For continued protection replace fuse only with a ( voltage and current specification) fuse. Most devices include that because the right fuse will fail and prevent a fire, which is the big liability issue.

 

Thank you both for the input!

No step up or anything like that - just 5v. I will consider wether to put a fuse anyway.

I've been reading I don't know how many pages and documents about CE certification and it does seem the EMC part is the big headache. Or let's say the expensive one that is definitely not possible to perform by myself.