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USB power supply puts 220 Mains power out on USB jack

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Re: USB power supply puts 220 Mains power out on USB jack

#111
A true isolation transformer has an earthed copper shield wound in between and physically separating the primary from secondary windings, anything less is unsafe.

One of the many reasons I detest "double insulated" equipment, as it is impossible to determine if it has been designed for safety or not without ripping it apart and destroying it.

This is a real issue in Australia as our regulators do no regulating and most equipment I have investigated does not comply with Australian Standards even though manufacturers lie and put standards compliance numbers on them.

Also the Australian Standards should be considered an absolute Minimum not "super safe".

Re: USB power supply puts 220 Mains power out on USB jack

#112
post #66

Not sure if HN knows about Mehdi Sadaghdar's (aka ElectroBOOM's) YouTube channel, which is somewhat similar - but takes a more lighthearted view on electronics. E.g. Compare Big Clive's mention of a full bridge rectifier in the video vs Mehdi's YouTube video of the same thing :) https://youtu.be/sI5Ftm1-jik

Ah, yes - the FULL BRIDGE rectifier-man :D

Re: USB power supply puts 220 Mains power out on USB jack

#113

A true isolation transformer has an earthed copper shield wound in between and physically separating the primary from secondary windings, anything less is unsafe. One of the many reasons I detest "double insulated" equipment, as it is impossible to determine if it has been designed for safety or not without ripping it apart and destroying it. This is a real issue in Australia as our regulators do no regulating and mo…

Does the Australian Standards body require that devices are sent to them for testing? Then there could be a database you could check as to whether a device has passed.

Re: USB power supply puts 220 Mains power out on USB jack

#114

Earlier quoted context omitted.

>for them to study For them to study, or for them to destroy the evidence so that you absolutely could not take them to court.

> so that you absolutely could not take them to court. Did he miss an opportunity or an opportunity cost?

I wish their was a class action every time a developer leaves an unpatched bug in their software...

Re: USB power supply puts 220 Mains power out on USB jack

#115
post #93

Earlier quoted context omitted.

I don't get it. They made transformers like that for about 80 years in America, but if a Chinese person does it, it's crazy and dangerous? It looked like she was doing a pretty good job.

Nobody said anything about America or China. The listed uploader on the video even suggests it's from India. So quit yer trolling. The transformers made 80 years ago were indeed dangerous. Generally they used paper insulation soaked in fire retardant chemicals. There are a couple of observations I make about this video: 1. She's working amazingly fast and clearly with great skill. However, there's very very little ti…

But would a machine do better? Machines can miss too.

Re: USB power supply puts 220 Mains power out on USB jack

#116

If you are wondering "How could an isolation transformer ever get past QC with abraded or nicked insulation?", you might find this video interesting: https://www.youtube.com/watch?v=HEJn74Z3wHk

I think that video has been sped up somewhat....

Why do you think it's sped up?

There's surprising amounts of skill in these unskilled / semi-skilled jobs.

If you're sitting at a machine winding transformers for 8 hours a day, and paid for each item you make (and fined for each item that fails test) you quickly get faster at winding transformers.

Re: USB power supply puts 220 Mains power out on USB jack

#118

How do I know what I'm buying is safe? I've sworn by the Nexus chargers in their various incarnations and http://www.amazon.com/Charge-Charging-Station-Micro-USB-Sams... (I have a Tronsmart and an Aukey vertsion)

I play Ingress a lot (a GPS based mobile game where you run around a lot in the real world so most players use external batteries) and at least 60-70% of the whole community uses Anker products. I personally know at a dozen people who use Anker wall plugs and all of them (including me, 1 wallplug and 2 battery packs) are very happy.

When talking about Ingress, I suppose you primarily talk about USB power packs. These are not as dangerous as power supplies that are connected to 110V or 220V (although they can catch fire).

Instead of trusting a particular brand, I think it makes more sense to trust the various security certifications that were created for this purpose.

The ones I am aware of are:

* TÜV Nord, TÜV Süd, TÜV Rheinland (TUV, Germany)

* GS (Geprüfte Sicherheit, Germany)

* UL (Underwriter Laboratories, US)

* CCC (China Compulsory Certification, China)

There are probably more that are trustworthy and that actually check the safety of the devices.

Re: USB power supply puts 220 Mains power out on USB jack

#120
post #45

Earlier quoted context omitted.

Anker and recently Aukey. And iOrange for cables. The problem is that smaller brands hit the Amazon lottery and get a lot of early 5-star reviews, then swap out their product with one made of cheaper components. I think for Anker, their brand has become a bit bigger than is gamble-able on a bait and switch, so I'm continuing to use their products.

Anker is ex-Google employees.

Interesting! Source?
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