Bogus IP protection (?)

One reason may be marketing. A good percentage of people who order the wrong item won't bother to return it.

Another reason might be an attempt to reduce the return rate for wrong items.

A good percentage of people have no understanding of how to match a power adapter with a specific piece of equipment and no understanding of what may happen if you connect a 12V adapter to a 5V port.

So it's best to leave that to those who can actually measure the V and check the polarity and make sure there is enough A.

Then those who get it wrong can't make silly claims like I didn't see why 12V would be a problem for a 5V device because it was the correct connector so I'm suing you for $$$ for damaging my equipment.

I recall an individual who wouldn't let me get a

How about cordless power tools and the idea of making a simpled corded adapter so that at some future point it's simple to keep the tool running even if the battery manufacturer has moved on yet AC mains is still a thing?

These days it seems that the cordless tool manufacturers are simply using "USB charging" or a similar protocol.

Some cordless tool manufacturers do offer a corded adapter, or Ridgid does, and various owners of the tools have reverse engineered the protocols, and made their own.

The other day I bought a maintenance-free lead-acid battery with 900+ cold cranking amps, it cost less than a usual two or three hour drill battery these days, though I was able to find a remanufactured drill battery for my 20-year old drill, as the original manufacturer "went out of business", say, or rather, "ended support".

So it'd be simpler for me to have a little battery cart and corded adapters to tools, also much less expensive, also much less prone to becoming useless despite not being used, probably filed under "right to repair".

The "value engineering" here is a lifetime bit not the "value engineering" of the disposable variety.

Which is considered disposable itself, ....

There's no conspiracy. Most people who furnish a wart with a product just don't worry about it.

We assign a model number to the warts that we resell, and put a sticker on them.

When I buy something, a hub maybe, I write on its wart to keep track of what it's for.

I have some warts on my bench for general use. I color code the barrel connectors so I don't poke a 24 volt one into a 5-volt box (again).

A dual-banana-to-barrel cable is cool because it lets me power things from a bench supply and ramp up voltage and see the current.

We try to design products that tolerate +-24 volts without damage.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

But, they will *find* said items by searching for "power adapter for a thingamajig 2000" -- which may also be listed (as in "advertised") as "... and a whatchamacallit 9845, gizmolator 23 and discombobulator 8". You expect the vendor to stand behind these claims -- especailly to the extent of not *damaging* any of those listed products for which you may be purchasing it. (as that would likel motivate you to discredit the seller!)

How would they KNOW it was "wrong"? Presumably, the unwashed masses would just plug it in and see if it works. And, if you stand behind your claim for the listed applications, it *should*, right?

Then, those folks would likely not even know to look for such markings on the adapter *and* the powered device.

But, you're not telling those people what the offering can be expected to produce -- until they have it in their hands and can see the obfuscated markings.

"You CLAIMED, in the listing, that it would work for my thingamajig 2000. I don't bear any responsibility for *interpreting* the electrical parameters of said device as I relied on your assurances that it WOULD work for my thingamajig 2000. So, YOU have claimed fitness for a specific function..."

See? I just don't understand what it buys them to take the extra step of obfuscating that information PRESENT IN A PHOTOGRAPH (not *claimed* in the listing).

Sony and Siemens products seem to also be "backwards".

I have a few digitally programmable bench supplies to which I connect an appropriately terminated cable. This lets me monitor (and limit) power consumed (as there is no guarantee that the kit is functional and why would I want to risk damaging a power adapter?!)

I've seen cases where products were developed and advertised with the identities of "select" components obfuscated -- until you placed an order for one.

And, some products where the markings on the components have actually been ground off.

But, these are so easily worked-around as to be laughable (if I wanted to reverse engineer your device, do you think I'd need that information? Or, that the lack of a schematic would deter me?)

Putting charge *into* a battery is a lot less challenging than ensuring you can get it out, fast enough.

And, the corded adapter has to ensure it can make available the startup and run currents (accommodating cable losses) of the particular powered device.

One of the advantages in the designs of battery-powered tools is the proximity of the power source to the load.

I hate the new 'universal ' barrel plugs/sockets from Asia... they 'claim' to be universal 2.1/2.5 mm. IME they're utter crap. Plugging a universal plug into a 2.1 socket it will fall out with the slightest of pressure- e.g socket on the bottom of a wall mounted device, plug plugs in from below. Weight of cable means it's totally unreliable and likely to fall out onter it's own weight. Only solution, it seems, is to throw away my 2.1 sockets and replace with 2.5 version. Then all my legacy wall warts that are 2.1 are bin jobs...bummer

Some of my devices use a barrel connector that has small "wings"; plug in, rotate 90 degrees and the "wings" prevent it from being removed, accidentally.

About the *only* thing barrel connectors have going for them (from a user's perspective) is they mate easily -- assuming you already have the correct partner!

We use a threaded barrel connector on our products so a user can elect to use a threaded cable.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics