Work in many houses etc and lots of customers seem to be in the habit of always leaving phone, computer ipad, kindle etc chargers plugged into the mains some even have a bank of sx plugged into multiway sockets on the floor or on the worktop.

Question are they a fire risk as the power is still going through the transformer part and cable, eg overheating shorting out, wear and tear on cable, electrocution risk from the charger.

and

Are they using negligible amounts of power.

Place i worked in a few years ago every plug had to be switched off and plug removed every night in case of fire, and the plug would be seen in socket and their would be questions asked

It’s a potential risk. My son always leaves his phone on charge on his bed at night. He’s 19 and just won’t listen – the things get bloody hot. He nearly killed our ‘big’ laptop’s charger by having the brick under a cushon – it was red hot.

I tend to not leave chargers plugged in

fakey chargers more so than genuine ones, I personally switch off at wall when not in use

pics

I leave them plugged in but switched off when not in use.

Deffo a bigger risk when the device or charger is on soft furnishings (says the fire brigade).

https://www.dwfire.org.uk/safety/safety-at-home/mobile-phone-chargers/

It’s only a risk when they are either damaged or dodgy imported ones. They are designed to be left plugged in – in fact there was a campaign years ago to reduce the amount of standby current they (and other things) used, and they reduced it to tiny amounts.

There’s no ‘shorting out’ because this would blow fuses or explode things. And there’s no wear and tear either – everything’s static. Maybe some big old fashioned transformer would get warm and degrade over the years, but they aren’t made that way any more.

There’s probably more chance of the battery catching fire when it’s in use, but even then that’s not very likely because a decent device has overheating protection on the battery and charging circuit.

MacBook Pro chargers cut out if they get too hot.

An undamaged charger for a phone, tablet etc should be just fine left plugged, particularly if there’s no device charging on it.

Leaving the device constantly charging is a different matter altogether, not good for the battery.

As for having 6 or so plugged in to a multi-plug. No issue, even 6 MacBook Pros are only going to add up to about 600W so way way below what the socket is rated for.

The risks come from having too many high power devices; hair dryer, electric heater etc. And also from dodgy substandard cheap stuff.

And also from dodgy substandard cheap stuff.

This. Big Clive on YouTube has done some interesting teardowns of the cheap and nasty AliExpress stuff.

I’m not a fan of Apple’s latest decision to stop providing chargers on cost- sorry, environmental grounds because no-one is going to buy a genuine Apple charger if it’s not included.

We only have genuine chargers or Anker ones. FIL used to have various cheapo chargers for phones – they didn’t last long – burnt cables etc.

I’m not a fan of Apple’s latest decision to stop providing chargers on cost- sorry, environmental grounds because no-one is going to buy a genuine Apple charger if it’s not included.

If people upgrade their phones, tablets, etc on a regular basis, just how many chargers do you imagine the average, tech-oriented household is likely to have, and how many more are they likely to need?
Anyway, there are loads of quality chargers available from the likes of Griffin, Belkin, etc, which are reasonably priced for it not to matter a damn if Apple, or any other manufacturers go the same way.
Far more important is the complete cluster**** that is the introduction of USB-C, which is encouraging the production of loads of different cables, chargers and other products due to the lack of a coherent standards policy.
https://onezero.medium.com/usb-c-was-supposed-to-simplify-our-lives-instead-its-a-total-mess-626bb2ea3688

What Mols said.

My mum’s been pulling plugs out of walls before going to bed since the 1970s. Realistically the risk today is from shite Far East devices that don’t conform to BS1363.

How do you think those usb charging sockets work on mains switches? Mine have no on off switch. Use proper chargers and you’ll be fine.

I leave my chargers plugged in and the socket switched on permanently (they’re all either Anker or Apple, 5 total), never had an issue. An Anker one gets warm but not hot if there’s 2-3 things charging off it, the Apple ones don’t even get warm. The only charger I used to unplug was the cheap/nasty one that came with my Magicshine lights years ago and were known to explode.

Leaving the device constantly charging is a different matter altogether, not good for the battery.

Not these days. Way back, if your battery charger was just a power supply connected to a battery then this was true. But when you have a modern electronic device it will shut the current off when it’s charged.

In fact, lithium ion batteries explode if overcharged, so they all have overcharge protection circuits built into the battery as well as the device.

My mum’s been pulling plugs out of walls before going to bed since the 1970s.

I had a girlfriend in the 70s who’s dad was a fireman. EVERY plug from every socket (except the fridge I assume) came out at bedtime. He’d been to too many fires started that way I suppose. Not strictly relevant to the op and bloody annoying if you’d set the ‘video’.

I hope not as we have 5 or 6 that are always plugged in and always switched on.
But as above, all are Apple plugs, maybe 1 Amazon one from a Kindle. None get warm.

I wouldn’t just equate Apple with “must be good cos it’s expensive and a proper brand”.
Certain genuine Apple chargers have a history of getting either very hot, or catching fire. Mine would be too hot to touch, but only if using laptop whilst connected to mains and charging at same time.

Does Amazon make chargers under their Amazon Basics branding? If so, having seen other Basics stuff, I wouldn’t trust it to be even fit for purpose, let alone safe to leave unattended. Kindle I would expect to be perfectly fine.

Also “unattended” while plugged in depends on whether the device is being charged or not. If it’s just the charger plugged in but not connected to anything, there’s basically no load so shouldn’t get hot. And if it does get hot when not charging then it’s probably failed and shouldn’t be used at all.

@andytherocketeer:

Take a look at this teardown comparing an Apple charger to a cheapo one. Big differences:
Apple version is one the left, cheapo on the right:

Full article: http://www.righto.com/2014/05/a-look-inside-ipad-chargers-pricey.html

Lots of similar teardowns by folk like EEVBlog and BigClive. Some of the dodgy import chargers have basically no protection circuitry and dangerously small tolerances between the primary and secondary voltages.

If people upgrade their phones, tablets, etc on a regular basis, just how many chargers do you imagine the average, tech-oriented household is likely to have, and how many more are they likely to need?

When I upgrade my phone, the old one plus charger goes on eBay, or to a family member. It’s then their charger and I’m not going to steal it to refill my own phone.

Secondly, most new phones support fast charging (typically 25-40W, but up to 120W is now available). Your old iPhone charger dribbles out electricity at a miserable 5W.

Not that many devices come with a charger any more – a USB cable, certainly, but typically you need a phone or a tablet to get a charger.

Anyway, there are loads of quality chargers available from the likes of Griffin, Belkin, etc, which are reasonably priced for it not to matter a damn if Apple, or any other manufacturers go the same way.

I suppose you could argue that if you’re willing to spend more than a grand on a phone anything less is reasonably priced. Ultimately I object to being asked to spend another 15 quid (which is roughly the price of the cheapest USB-PD charger from Currys, when it costs Apple about 50p to include one in the box.

On top of that, to fast charge an iThing you need a USB-C to Lightning cable, not the generic USB cable that’s in the box. Add another tenner to the price.

At least they’ve standardised on the USB-PD standard, but good luck identifying that on PC World’s website or on the rack at Tesco. I think your average person will pay the Apple tax at the time of purchase and give them another thirty pounds in the shop for their OEM charger and cable (kerching) or they’ll look on eBay for the cheapest thing that’s advertised as a “100% GENUINE APPLE IPHONE CHARGER HONESTLY NOT A DANGEROUS FAKE IMPORT THAT MIGHT BURN YOUR HOUSE DOWN ONLY 99p”.

molgrips
Free Member

Not these days. Way back, if your battery charger was just a power supply connected to a battery then this was true. But when you have a modern electronic device it will shut the current off when it’s charged.

In fact, lithium ion batteries explode if overcharged, so they all have overcharge protection circuits built into the battery as well as the device.

Sorry but he’s right, leaving them constantly charging does **** them up and I’ve had that verified by a Windows tablet manufacturer (linx) recently. We were planning to use one of their tablets as a display on a product we’re working on.

The reason is because it charges to 100%, then stops charging. Over time the battery runs down to 95% and the charger kicks in again and tops it back up. For whatever reason this kills the battery in a much shorter number of cycles than regular use does.

Maybe you meant leaving them plugged in overnight? In which case you’re absolutely right.

The reason is because it charges to 100%, then stops charging. Over time the battery runs down to 95% and the charger kicks in again and tops it back up. For whatever reason this kills the battery in a much shorter number of cycles than regular use does.

This is a slightly different situation though. It strikes me that Linx, being a cheapo manufacturer have done something on the cheap. My laptop for example charges the battery to 100% then it stops charging and runs off the power supply, if the battery/charging indicator on the desktop is anything to go by. This is also backed up by the temperature of the thing – it does not keep getting warm then cool as it charges and discharges; and the fact that back in the days of removable batteries you could remove the battery once charged to 100%.

You can work it out for yourself.
See how hot the charger is when it is connected to a device and charging (it range from warm to hot). Do the same when it is not connected to a device and not charging (it will be cold as it is not doing anything)

An FM for a large company reported that they had a small number of phone charger fires. For their new office fit outs, twin sockets are installed with USB charging outlets, no personal chargers allowed. I would recommend the installing the same at home where you regularly charge phones tablets or bike lights. It also frees up the sockets and generally looks tidier.

For their new office fit outs, twin sockets are installed with USB charging outlets

How is that safer than a separate charger? You’ve just moved the charger inside the wall where it has poor airflow, you can’t tell if it is getting hot, and you can’t do anything about it if it catches fire.

Plus you’ll need to change the socket as charging standard change.

Personally I use this as my main living room charger:

Four PowerIQ USB ports and one 30W USB-C PD port for my iPad Pro. If you’re worried about it looking “untidy” it can be mounted under a table.

Lithium batteries don’t like being left at 100% for very long; it will damage them, even if charging has stopped. EVs and other devices with very large batteries always have a buffer so 100% from the user’s point of view isn’t really 100%; they often come with the ability to set even lower limits as well. Those battery ferries in Norway cycle their batteries between 40% and 60% IIRC to maximise battery life.

Phones (and I guess laptops) don’t do this; 100% is 100%, as it means they can advertise a longer runtime and people tend to replace their phones in a few years anyway so running down the battery’s state of health doesn’t really matter.

I wish phones would come with an option to restrict the maximum charge, though. Especially when new I don’t need it to charge to 100% most of the time, I would rather extend the useful life of the battery instead so it still lasts a full day years down the line.

molgrips

This is a slightly different situation though. It strikes me that Linx, being a cheapo manufacturer have done something on the cheap. My laptop for example charges the battery to 100% then it stops charging and runs off the power supply, if the battery/charging indicator on the desktop is anything to go by. This is also backed up by the temperature of the thing – it does not keep getting warm then cool as it charges and discharges; and the fact that back in the days of removable batteries you could remove the battery once charged to 100%.

No, you’ve misunderstood because i’ve written my post badly.
When I said ‘runs down’ I didn’t mean say the device runs off the battery (and indeed the Linx devices do not), but rather it naturally discharges from 100% over a few hours/days. At some point it reaches 95% (or whatever the OEM has specified) and the charger boosts it back up to 100%. Repeat.
When I’m next in work i will grab the email and you can read it verbatim.

That was my point. Using your iPad for 1hr a day and then plugging it back in each day is going to degrade you battery performance faster.

However it’s not really relevant to the topic, it’s not dangerous to do that, just not ideal.

@phiiiiil: iPhones give a “Battery is sufficiently charged” message at 80%.

I think most modern smartphones optimise the charging so they charge at faster rate at lower capacity and slow it down as they approach full to avoid damage to the battery.

I wish phones would come with an option to restrict the maximum charge, though.

They do, if that helps.

My laptop maintains the battery at about 60% charge and if I know I’m going to need a full charge I can boost it up to 100% with a click.

Phone does the same thing – when it’s plugged in overnight it doesn’t actually refill the battery until just before I normally wake up.

How is that safer than a separate charger? You’ve just moved the charger inside the wall where it has poor airflow, you can’t tell if it is getting hot, and you can’t do anything about it if it catches fire.

… and I can’t imagine they’re particularly high quality either. You’ll likely get 2A shared across both ports, PowerIQ etc it won’t be. (If you find one that is I’d love to see it, I’d buy them myself.)

Phone does the same thing – when it’s plugged in overnight it doesn’t actually refill the battery until just before I normally wake up.

How’ve you managed that?

How’ve you managed that?

Modern phones monitor your use and charging habbits and so know that, generally, if you plug it in at 22:00, you’re not going to touch it again until 06:00 and so will not charge at max rate.

That’s good to know, I assumed my phone was recent enough but obviously not! On Android at least you used to have to root it to use an app that would stop charging at a certain point, it’s great stuff like this is starting to be built in now…

some interesting stuff above, think i will continue to unplug stuff and not leave charging unattended

There is some element of risk, but I’m going to suggest that it is often massively overstated. Why do I think that? Because the reality is most households up and down the country have chargers plugged in all the time, and devices left unattended charging; many offices and other workplaces will do too. There are only a small number of fires each year and only a fraction of them are caused by chargers. If people want to encourage them to be switched off either on environmental or safety grounds I’m ok with that, but the bit I don’t understand is:

Place i worked in a few years ago every plug had to be switched off and plug removed every night in case of fire, and the plug would be seen in socket and their would be questions asked

I had a girlfriend in the 70s who’s dad was a fireman. EVERY plug from every socket (except the fridge I assume) came out at bedtime. He’d been to too many fires started that way I suppose.

some interesting stuff above, think i will continue to unplug stuff and not leave charging unattended

The risk of a charger causing a fire whilst plugged in and turned off must be absolutely tiny. You need that particular charger on that particular day to have the particular fault which causes a fire without blowing the fuse (or RCD) AND the particular socket it is plugged into to be faulty such that the on/off switch doesn’t work. If your wiring/sockets are that bad, the charger is probably not the biggest worry!

Personally I’d suggest that its more important you think about where the device being charged is left. I see people leaving phones/laptops charging on sofas (where they can fall between cushions and get VERY hot) or on stacks of paper in offices.

I wondered whether not only does unplugging not help, it may hinder:

– Extra strain of repeated unplugging / replugging causes mechanical failure which may lead to an electrical fault
– Risk of standing on all those unplugged plugs in barefeet, which is far worse than having your house burn down

Incidentally, a few years ago a roadie friend of ours lost their kitchen after their dishwasher caught fire. 😲 Luckily (?) they were not home at the time.

https://www.hertsad.co.uk/news/dishwasher-fire-prompts-st-albans-dad-to-go-on-bike-ride-for-fire-fighters-charity-1-4538413

How many people are unplugging their dishwasher or only running it when they can supervise it?

but rather it naturally discharges from 100% over a few hours/days

I don’t dispute the content of the email, however I don’t think that a quality battery is going to lose 5% in a matter of hours. I use this laptop plugged in a lot and the charge indicator never moves off 100%. Unless it’s lying to me, I dunno. But you would assume that a laptop has been designed for this ussage pattern.

Personally I’d suggest that its more important you think about where the device being charged is left. I see people leaving phones/laptops charging on sofas (where they can fall between cushions and get VERY hot) or on stacks of paper in offices.

This feels more plausible to me, however again decent devices have thermal cutouts. My Samsung S6 did because I triggered it using wireless charging whilst using satnav.

If you are worried, look out across your town or city at night from a high vantage point, and consider that all the houses you can see probably have half a dozen charging devices and half a dozen chargers left plugged in during the day – along with a load of other appliances both digital and not. How many of them are on fire?