Discuss iPhone chargers. To test or not to test? in the Electrical Testing & PAT Testing Forum area at ElectriciansForums.net

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I used to test phone charges in a charity shop, never fried any at 500 volts.
Failed a few on cracked cases damaged wiring and pins.
 
Edition 5 of the Code of Practice takes a more risk assessment based approach. In other words, what is the product used for, what environment is it used in, what Class of construction is it, who will be using it etc...
Once that risk assessment has been made for a particular item of equipment, then a decision can be made on how and how often to inspect and/or test the said equipment.
 
Edition 5 of the Code of Practice takes a more risk assessment based approach. In other words, what is the product used for, what environment is it used in, what Class of construction is it, who will be using it etc...
Once that risk assessment has been made for a particular item of equipment, then a decision can be made on how and how often to inspect and/or test the said equipment.
Mmmm! That's their £2.50 per item down the swanny before they've started thinking about whether to test or not. ?
 
Trying to test a Class II charger for differential leakage or insulation via the plastic ISOD is not very sensible. But testing it for insulation or touch leakage to the USB output is a real thing and IMO should be done, given the number of counterfeit chargers in circulation with possibly inadequate insulation between the live side and the output. Plug a USB cable in and use the tester's earth probe to take an earth to the shield. You won't damage a good charger, or put another way, any charger that can't withstand 500V between the mains and user is not a good charger.

If there was some certainty that all the OP's chargers were genuine and have not had a hard life, the risk assessment might realistically limit it to visual inspection. Take any bunch of random chargers instead and while the probability is still low, the hazard associated with insulation failure of a substandard charger is a phone body connected to mains line, possibly even while it is charging happily, so there is measurable risk.
 
I may owe the OP an apology as I've just observed that an iPhone charger actually appears to have a metallic earth pin (and a class II symbol). Without pulling one apart I don't know the value of IR testing it that end. I like the comment about testing the USB output side.
 
Our first positive result for an insulation breakdown between input and output was on a laboratory power supply in a school in the 1990s. The Radford Labpack was a multi-output bench PSU of the 1960s/70s which, although generally well made, had a flaw in the wiring loom construction. Amongst the outputs was a 6.3V 8A floating (not earthed) supply for valve heaters and optical ray lamps, which unlike the other outputs was not separately fused, relying on the mains fuse to protect the transformer. Unfortunately the wiring in the loom was the wrong gauge and could not withstand the short-circuit current for long if this output was shorted by the user, resulting in general insulation damage to the loom. One possible result was the 6.3V wiring melting into contact with the mains line to the fuseholder, making the 6.3V sockets live with mains. As the secondary was floating, it continued working, with the experimental apparatus that students used to connect with bare 4mm plugs all being live with mains on one side and mains +6.3V on the other.

We sent out a warning to all organisations using our testing service, to send all units in for inspection and modification (the manufacturers were no longer in existence.) Dozens of units had insulation damage, although I can't remember how many actually had the output live with mains. I remember the head of the PAT department who might have been the first to discover the problem, having a rather heated conversation with one of the teams whom he suspected of not always testing insulation to PSU outputs. 'Why wouldn't you ******* test them?' was his question.
 
Our first positive result for an insulation breakdown between input and output was on a laboratory power supply in a school in the 1990s. The Radford Labpack was a multi-output bench PSU of the 1960s/70s which, although generally well made, had a flaw in the wiring loom construction. Amongst the outputs was a 6.3V 8A floating (not earthed) supply for valve heaters and optical ray lamps, which unlike the other outputs was not separately fused, relying on the mains fuse to protect the transformer. Unfortunately the wiring in the loom was the wrong gauge and could not withstand the short-circuit current for long if this output was shorted by the user, resulting in general insulation damage to the loom. One possible result was the 6.3V wiring melting into contact with the mains line to the fuseholder, making the 6.3V sockets live with mains. As the secondary was floating, it continued working, with the experimental apparatus that students used to connect with bare 4mm plugs all being live with mains on one side and mains +6.3V on the other.

We sent out a warning to all organisations using our testing service, to send all units in for inspection and modification (the manufacturers were no longer in existence.) Dozens of units had insulation damage, although I can't remember how many actually had the output live with mains. I remember the head of the PAT department who might have been the first to discover the problem, having a rather heated conversation with one of the teams whom he suspected of not always testing insulation to PSU outputs. 'Why wouldn't you ******* test them?' was his question.

I remember the Labpack power supplies well from the physics labs at my secondary school. Lots of different outputs, but absolutely no regulation.

I also remember melting a line right across the bench I was working at once. I had connected a length of wire across one of the outputs ready to create an electromagnet. Teacher not impressed!
 
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A few people on YouTube have some videos of them tearing down cheap usb chargers and the like

Alot of the cheaper ones have very poor seperation between mains input and low voltage output, and there have been quite a few reports of the seperation failing and mains voltage being present on the usb, this presents a shock risk & I would thinking the device plugged into it wouldn't be to happy also

So I would say testing that isolation is a good idea, likewise spending a little bit more on chargers
 
I’ve just spent the day testing about 40 iPhone chargers. Sticking 500v through them and they all pass. Does everybody agree that they have to be tested?
What are you ACTUALLY testing with a PAT tester and a charger? like what is there to test??
these types of switched mode powerpacks only have accessible 230v on the inlet pins. All the rest is either inaccessible or ELV output. Yes I've had issues with induced 230v but when you test the output with a low Z voltmeter the 230 disappears. I reckon if you want to be safe ( like in a school for example) have the supply sockets protected with a 10mA RCD.
 

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