Wall-Warts

[Anonymous]

Is there any particular reason why manufacturers couldn’t put a female power connector on the wall-wart itself and then sell connecting leads (with connectors on each end) in various lengths to suit the users’ needs? (I do realise there’s probably a maximum length limit).

So that when you have a bunch of equipment in close proximity you have something more manageable than the tremendous jungle of excess wire, whether folded/tied or not, to deal with.

[JourneymanParticipant @journeyman]

 

Like this perhaps, 2 5v USB out with through 13A

John

[Robert Atkinson 2Participant @robertatkinson2]

It’s down to cost. For small supplies a “wall-wart” is lower cost than a “soap-on-a-rope” power supply with a seperate lead.
Also if there is no mains lead it is much easier to meet radiated emissions requirements as the item being tested plugs directly into the line imedance stabilisation network (LISN a test box thet presents a standardised supply charateristic) with no cable to act as an antenna.

Robert.

[Anonymous]

Whoops! I think I’ve misled you by not being clear (mea culpa). I’m talking about the ubiquitous low-power 5V (or 9V or 12V etc) DC power adapters that plug into a mains outlet and have a lead coming out with the familiar low-voltage, coaxial power connector.

This kind of thing

https://www.amazon.co.uk/Adapter-Supply-100V-240V-24Volt-Available-Black/dp/B0BPY4MZJV/ref=sr_1_16?crid=266LBLQ7R1UI7&dib=eyJ2IjoiMSJ9.DUyjsDQgJP_4qvhKCHtzJLYv-J4WP65uQUatFzTPYVKED6r3RJpBOthxTNwHBleBTYznAZsQFYe5aDrjVaSmMpzet7E-XDqnEkiqkyPmEYkSsiylV5F7piYipFP6epIFkWajbcHSfLFJ5iYtkJ5vLvvrE_51Vget3jKRSs8i9CZrq_fUa1phkdkrOgUzYlCke65rNj1HfYeejT_G_1XzfSzpMDzzhB1suNpCq4dDVdE.fXycoFz6AqJEUjjd7ZPNtdxwAcDA8C5Tw1r6sWxIvs4&dib_tag=se&keywords=power+adapter&qid=1705346893&sprefix=power+adapter%2Caps%2C217&sr=8-16

[peak4Participant @peak4]

An issue might be one you’ve alluded to yourself.
USB ones are fine to have integral sockets, as the voltages and charging standards are clearly defined.

Other wall warts however are made in a large number of different voltages, and the devices they power even vary in polarity, as well as being a mixture of AC & DC.

Unless there is a dedicated style of connector for each voltage, then there are lots of options for damage or fire.
I’ve a universal laptop PSU, which does have a whole different set of connectors, each one telling the PSU what output to supply.

Bill

[Anonymous]

USB? What I said was “coaxial power connector” and the link above clearly shows what I mean.

[Peter Greene]

On Peter Greene Said:

USB? What I said was “coaxial power connector” and the link above clearly shows what I mean.

Yes I know, I referred to USB, as that defines the power characteristics as well as the shape of the plug, and thus creates a standard, where the only variation is the length of the cable, and requirements for ferrites etc.

Co-axial connectors often don’t follow any logical pattern.
I have wall-wart types, with co-ax connectors in at least 3, 3.7, 4, 4.5, 5, 6, 7.5, 9, 11, 12, 13V, etc, in both DC & AC variants, as well as at least half a dozen different diameters on the plugs, some of which vary polarity.
It’s a nightmare remembering which ones power which devices.
There doesn’t seem to be much in the way of a standard, other than with some laptop PSUs, where different voltages are different shaped plugs.

[Peter Cook 6Participant @petercook6]

As Robert says it’s down to cost. Not just the cost of the power supply, but the logistics costs – each cable length is an additional SKU to be managed, distributed and tracked. Which length would be included, or would all retail outlets be required to stock a choice and manage the pick and pack.

In addition there are the potential support and warranty costs. Customer plugs the wrong cable in and blows up the unit.

The manufacturing mantra is “keep it simple”.

 

[Anonymous]

Well, sure – that’s the stock pedantic answer. But it only really applies if the before and after versions of a product fulfil exactly the same function in the same way with no added value. (And if the after-version is intended as a replacement rather than a parallel product line).

[peak4]

On peak4 Said:

On Peter Greene Said:

USB? What I said was “coaxial power connector” and the link above clearly shows what I mean.

…I have wall-wart types, with co-ax connectors in at least 3, 3.7, 4, 4.5, 5, 6, 7.5, 9, 11, 12, 13V, etc, in both DC & AC variants, as well as at least half a dozen different diameters on the plugs, some of which vary polarity.It’s a nightmare remembering which ones power which devices.
There doesn’t seem to be much in the way of a standard, other than with some laptop PSUs, where different voltages are different shaped plugs.

I do electrical testing and repairs for a local charity shop, and I have dozens of PSUs stashed away in my work-room, all different and mostly not compatible with anything.  As far as I can tell there are no standards of any sort, apart from USB, and even there one has to check the available current output.

There are some wall-warts with built in female connectors, but I have only encountered them on low voltage light strings.  They are as un-standardised as all the rest.  It’s all a bit of a nightmare, and very frustrating when things are donated without a PSU (as they regrettably often are).

George

[peak4]

On peak4 Said:

Yes I know, I referred to USB, as that defines the power characteristics as well as the shape of the plug, and thus creates a standard, where the only variation is the length of the cable, and requirements for ferrites etc.

Co-axial connectors often don’t follow any logical pattern.

 

I wasn’t trying to create a standard – just seeking to give more flexibility to what’s already established. And yes, I too have the nightmare of different voltage supplies, and of different sizes of coax power connectors but those are separate problems. using USB connectors may solve that – if it can handle the current – and when it does, I’ll be glad. But until everyone agrees to it ….

[BazyleParticipant @bazyle]

I can assure you the leads on the low voltage side are no longer than thought necessary to please the customer. About 10 years ago for a product I had to alter the spec from 1m to 1.5m so the device could more easily be placed on a table. This increased the unit cost by about 40p in half million volumes.

[Martin KyteParticipant @martinkyte99762]

What’s stopping you cutting to length and fitting the connector of your choice?

regards Martin

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Peter, maybe you are looking for something like this;

https://pro.maplin.co.uk/products/3-12v-1a-mini-regulated-voltage-adjustable-power-supply

Regards Nick.

[noel shelleyParticipant @noelshelley55608]

Nick has pre empted me BUT for people who understand, it MIGHT work ie the universal wall wart ! but as there are so many plugs/sockets/polarity/ voltages it would be a nightmare more likely to destroy things than be a God send ? Noel

[Peter Cook 6Participant @petercook6]

If cost is not the issue, something like this Ciocks DC7 PSU could do the job. Seven independently switchable 9/12/15/18v outputs ( albeit only 6W each), plus cables.

[Nicholas Farr]

On Nicholas Farr Said:

Hi Peter, maybe you are looking for something like this;

https://pro.maplin.co.uk/products/3-12v-1a-mini-regulated-voltage-adjustable-power-supply

Regards Nick.

Not really Nick. As explained in my original post, it’s the length of the wire that I’d like to be able to easily customise.

[JourneymanParticipant @journeyman]

There you go😄

John

[Neil WyattModerator @neilwyatt]

Most do nowadays, don’t they? Certainly in the future this will be a no-brainer.

The new USB-C chargers typically offer up to 24W at 5 V, 9 V, 15 V and 20 V at between 0.5 and 5 amps. Which means they can supply MOST things needing charging around the house, even laptops, the only caveat is that unless 5V at low current is required the device needs to be ‘smart’ and able to ask for the supply it needs.

They also have a USB-C socket so you can choose any length you want.

Alternatively, lots of simple 5V chargers which take USB-A allowing you to swap leads.

I have a variety of leads with USB-A to various power connectors in several lengths that came with different items.

Neil

[peak4Participant @peak4]

I appreciate what Peter is after; that is tidying up the wiring, but I’m not sure there is an easy solution.
Personally, coming from a telecoms background, I use double sided Velcro tape, which does make a neat job, and is easily removeable for future modifications.
I also change cable lengths with solder and heat shrink tubing, but that’s more problematic if the manufacturers have used co-ax cable as well as plugs; some just use round or flat 2 core.

To add the usual topic diversion, my issue when travelling is too many mains connector cables needed.
Again my solution is heat shrink and solder; two layers of insulation on each core, with a further 2 layers on top, and checked with a megger.

I have others with UK & US plugs; there’s no issue with overloading as the high voltage power demands are quite small.
The end with the blue band, has been Dremmel modified to fit a cloverleaf, so it can be used for my laptop  charger.
I did check, the original cloverleaf – UK cable is only 2 core.

Bill

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