dynax":3hetxb7j said:
Hi Eric, i was thinking of only doing limited edition runs of say 10-20 pieces, as far as i can see the product i make would be exempt from the lvd as it's power requirement is well under the minimum of the standard, and as the psu will have it's own compliance there should be no problems
AIUI, it's not quite like that: if you modify a CE marked item, or combine it with something else into a new item (as Sheffield Tony mentioned, I think) it becomes a new product in the eyes of the law, and thus requires a declaration of conformity in its own right.
So if you sell PSUs separately you can to an extent rely on any declaration they have, but if you sell them WITH something you have made, then the whole lot, TOGETHER, has to have a declaration. That's when a dodgy PSU would get you (in the main).
I guess that's reasonable. I can think of any number of items which independently are reasonably safe, but together are dangerous. Sugar (or burned toast) and weedkiller, for example.
For the consumer market, Trading Standards departments (at the local council) are responsible for prosecutions. Again AIUI, they'll only get involved if a trader is knowingly selling something that doesn't have a valid Declaration (or has false documents), or has deliberately turned a blind eye suspecting something might not comply.
If you bought a PSU in, in good faith, and had done diligence to establish it came from a reputable manufacturer, etc., you should be fine. Assuming it does work as stated... But if it is dangerous, or if you bundle it as one product, any misbehaviour it may have does become your responsibility.
The current topical disasters are really cheap mobile phone chargers and Christmas lights. Some of these things can electrocute, or start fires, and retailers can't hide behind documentation provided. And IMHO, that's entirely reasonable.
But Damien Hurst got away with selling animal carcases in tanks of formaldehyde, because it was "art" (the "F" is silent).
I'm not making them for profit, it's just something to make in my spare time and making use of surplus materials,
The profit element is sadly irrelevant. If you sell them you're trading.
But as I said, you can protect yourself by being careful with the quality of bought-in items you sell. You can also use circuits that are unlikely to be a problem. Make some, try them out, run them right next to an AM radio (or find someone with an RF spectrum analyser who might be persuaded to check).
If the circuits are all analogue, you're on much safer ground (speaking of which, pay attention to electrical safety, if that has relevance). Digits tend to cause problems where clock oscillators are involved or high speed data lines, but for low frequency oscillations the remedies are pretty well understood - ferrites and the like usually work well. That said, for years a well known retailer sold audio amplifier kits that, if carelessly assembled, would settle into oscillation around 100kHz, and I still own a rather nasty car booster amp that does the same.
The problem nowadays is the number of RF bands actually in use. In the old days things generally didn't oscillate much above a few MHz, and even then (a) it didn't get very far, (b) things had good metal cases (Faraday cages), and there was nothing in the domestic environment that might be upset (well, possibly the telly), Now we use every bit of the RF spectrum we safely can, so life is much harder. The EMC rules include susceptibility to interference as well as emissions for that reason.
Can you use batteries instead of mains? That makes your compliance much easier, probably.
E.
