While browsing my filing system (also known as the office floor) I came across a news item from 2013 about a real dodgy Chinese knockoff of the Apple iPhone chargers. A Chinese women was electrocuted when she answered her Apple phone. Now you cannot get electrocuted from an iPhone of course because it runs on extra low voltage (ELV) but it was plugged into a charger at the time. This suggests that the charger, which was not Apple branded, did not have any isolation between the mains power and the ELV output.
Credit where credit is due and while we can easily criticise Apple for all sorts of things they did the right thing by offering their replacement chargers at a discounted price in many countries, including New Zealand.
It was not the first time that phone chargers has caused electrical shocks and there was another case in China soon after the fatal one mentioned above. As a technician I am very interested in the results of any investigation into dangerous phone chargers but a quick poke around the internet did not bring anything to light.
Designing a charger that gives sufficient isolation between the mains voltage and the ELV output is not rocket science! Insulation, isolation, testing, compliance etc are all important things. So come on manufacturers get your act together!
UPDATE: Yep, sure enough, these crappy chargers don’t have enough isolation between the primary and secondary (amongst a whole lot of other problems)! This is a video from Dave Jones over at the EEVblog who did a teardown of two of them: