Mains USB charger for small devices ???

[Wayners]

@Jurassicspark

Op mentioned headphones and bike lights so tv would be fine.

Yeah they tend to be low power unless you have a realy good TV which can have a 2 amp USB

 

[frank999]

Thanks all for your replies, will try and answer best I can.

I dont have a TV any more.

The USB sockets on my laptop (used the charge the lights and headphone) are wearing out, so decided I need to stop using them - hence the search for a charger.

So surely the below devices must have some 'charging' circuitry, and on my laptop I have different standards of USB - which from what I understand have different load capacities ... I have one of these I should use, think that can tell me the current drawn and supplied between device and charger ...

The headphones and bike light simply came just with a USB cable - no charger, this is my light below, rated 5v 1.0a:

The headphones (these are similar - but not the exact ones), are the same, no charger, just a USB cable:

 

[Harry Bloomfield]

The headphones (these are similar - but not the exact ones), are the same, no charger, just a USB cable:

Rare is the item these days, which is supplied with a USB charger. The reason being most people already own lots of suitable chargers, so why supply more?

 

[ebee]

wishing to avoid the terrible chinese tat chargers found on Ebay

Are you thinking that you do not trust a race of people that wear hats that look like lampshades?

 

[frank999]

The spec is 5v 1a for the Ikea 'charger' = point taken that it is not actually a chargrer - could one say inverter ?

I have an IOT device I have also bought the charger for, again the IOT device rated at 5V, 1.0a and comes with no charger, it has no battery - so one could presume that is a simple case of the charger acting as PS, ie no battery to charge.

Load tested the 'charger', and it cut out at about 1.2a:

 

[morqthana]

Hi,

I have been looking for a quality mains USB charger/hub, and wishing to avoid the terrible chinese tat chargers found on Ebay.

Anker make good products.

 

[ericmark]

The power supply, cable, and device all can limit the charge rate, found even turning the connector over can change the charge rate.

I like everyone else I should think have a load of leads, and I know the colour of the plastic in the plug.

Should show the charge rate etc. But I also know this is not always the case. And even with Samsung written on the charger, it does not mean it will be fast.

Two extension leads, both from Lidi, and one is fast and the other slow. As for rear bike lights, I have one which seems to last longer than the main battery, but the other seems to last no time at all. And one does not realise when the rear lamp has failed, and the front one comes from the traction battery, so how long it lasts depends on how hard I peddle.

I liked the old hub dynamo (not really a dynamo, it was an alternator) but it was decided the output was not high enough, so discontinued, today will LED they would have been ample. And the clip on can wreck a tyre.

 

[Harry Bloomfield]

And the clip on can wreck a tyre.

Back in the day, I found the metal drive cog wore out, on top of the 'bottle', quicker than the tyre sidewall.

 

[ebee]

Back in the day, I found the metal drive cog wore out, on top of the 'bottle', quicker than the tyre sidewall.

Blooming Heck Harry, thou must have been a fearsome peddler!

 

[frank999]

OK, so I tried testing the headphones:

Amazon.in

.. but I think the batteries are stuffed, so cant get any good readings, ie its not taking any curent (0.018a 0.086w @ 5.12v)
I had up till I stuffed the batteries (by charging with the Ikea charger) been charging it on my laptop ... so @ericmark - could one assume the headphones are only designed to be charged on a Laptop USB port ??, and the output from the Ikea charger is greater than the USB ports on my laptop ?, my laptop US port spec is:

USB 3.0 (2)​

USB 2.0 (2) 1 port with USB charging support
I read in this link

How Much Power does USB Port Output? (USB 1.0, 2.0, 3.0)

Different USB ports give different output power. The output power from a USB port varies according to the version of the USB as well as the

www.etechnophiles.com

... that USB 2.0 can provide up to 500mA 2.5w, and USB 3.0 900m,A 4.5w.
I have plugged the headphones into each, and assuming the USB 3.0 port has been used, 900mA is nearly the 1.0a ourput of the Ikea Charger, so bit confused as to why the IKEA charger I have used has stuffed the headphones.​

 

[endecotp]

could one assume the headphones are only designed to be charged on a Laptop USB port ??

No.

bit confused as to why the IKEA charger I have used has stuffed the headphones.

It would take a lot of work to discover what has gone wrong. You haven't done anything wrong and the headphones have died, that's all you will ever know.

 

[Harry Bloomfield]

I had up till I stuffed the batteries (by charging with the Ikea charger) been charging it on my laptop ... so @ericmark - could one assume the headphones are only designed to be charged on a Laptop USB port ??, and the output from the Ikea charger is greater than the USB ports on my laptop ?, my laptop US port spec is:

No, as I already said - the USB charger, will output current up to it's maximum, only if allowed to by the device you plug in to charge. The device will accept a charge, only up to it's maximum, and no more. So the actual charge, is set by whichever of the two has a lower charge limit.

 

[frank999]

'It would take a lot of work to discover what has gone wrong' - guess we'd need to do a BigClive.com style breakdownof the headphones ...
But I'm now paranoid of plugging small devices into this new Ikea charger

'So the actual charge, is set by whichever of the two has a lower charge limit'.

I remember I plugged my bike light into a samsung phone charger, - I think it may have been a fast charger - but that it stuffed the battery on that ... in that circumstance how did the bike light not 'limit' the charger, and in the same way - why the Ikea charger.


If a device is plugged into either 1) a USB 3.0 900ma 4.5w capacity laptop port - or 2) the Ikea 1.0a 5.0w charger - one should expect it to be charged in a similar manner, yet the Ikea charger stuffed the batteries ... dont know, still confused.

 

[morqthana]

It would take a lot of work to discover what has gone wrong.

No it won't.

my rechargable headphones (these are cheap chinese ones)

 

[spile]

But I'm now paranoid of plugging small devices into this new Ikea charger

Think of a 240v socket in your house. It can provide any current from 0 to 13A without you having to worry about it. Presumably, you don't get paranoid when you plug in Christmas tree lights or a fan heater in the SAME socket!