Like clockwork, my daughter bounces around in her bed demanding companionship and hugs and silly voices until about ten thirty. Like clockwork, my son, despite many and varied threats, comes downstairs at eleven thirty, midnight, and zero dark thirty, to demand we turn his music player back on. This is just kind of background to why it’s so damn hard for me to get any writing done. I’ve been hovering at “Just gotta draw some sort of conclusion and we’re good to go,” on the next War of the Worlds article for like three weeks now. I totally should have it ready for next week, I mean, unless some other big exciting distracting thing were to happen Thursday or something.
So instead, I’m going to rant for a bit about AC Adapters. You know what’s bullshit? AC Adapters.
As part of cleaning up my workshop, I went through and sorted all my AC adapters and made notes of what I had and their identifying markings. I have 95 AC adapters, not counting the USB ones. Here is what I have found:
- Despite there being a wide range of kinds of connector for an AC adapter, there is absolutely no relationship between the kind of connector and the voltage, amperage, polarity, or even whether the output is AC or DC. There is also no standard set of names for the different sizes or form factors of connector.
- Speaking of, AC to AC adapters are a thing. I’ve got three of them, which output 9, 8 and 24 volts AC. Only the 24-volt one is visibly different from every other AC/DC wall bug I’ve got, which seems like a recipe for blowing myself up.
- There’s almost a correlation – the 5.5mm barrel plugs mostly belong to 12 volt supplies and the 3.5mm barrels mostly go with 5 volt, but there’s loads of exceptions, and there’s also a handful of other sizes at complete random.
- In addition to the critical features of length, inside diameter, and outside diameter, connectors have a number of other physical properties which don’t directly impact what they can be plugged into, such as the color of the dielectric, whether or not there’s a ridge on the sleeve to improve friction, or whether the inside is a complete metal sleeve or a spring clip. These traits could easily encode information by correlating to, say, the voltage, amperage, or polarity of the output. They do not.
- The overwhelming majority of the adapters I have use 5.5mm barrel plugs. The thing is, there are two common inner diameters for that form factor. Measuring the inside is not something I have a convenient way of doing, and the larger size will fit a jack meant for the smaller one – it might even work, just be a little loose. To make matters worse, a lot of these have a spring clip inside, so potentially they actually could fit both sizes fine.
- There seems to be great disagreement among the manufacturers of these things whether it’s “Adapter” or “Adaptor”.
- Most of them don’t have a wattage listed, but among those which do, only some of them make sense. Watts should equal volts times amps, but sometimes… They don’t. Is this an efficiency thing? Or is one a max and one an average?
- When did the NEMA C5 (“Mickey Mouse”) plug become a thing? I know a few years ago, I had to buy one because I owned zero and suddenly needed one because I bought a new computer which needed it and didn’t come with one, But suddenly, about half the power bricks I have use them. The older ones use a C15 (Traditional computer power cord) or a C7, but it seems like C7 is on the way out. There’s one that takes the non-official variant asymmetric C7.
- I’ve got twelve adapters whose markings do not specify the sleeve polarity. D-Link is particularly lackadaisical about this. This wouldn’t be a huge problem, except…
- One. I own one AC-DC Adapter which is marked with a positive sleeve polarity. Every other one that has a marking is negative. 9 volts, 800 milliamps, 5.5mm plug. A normal sort of voltage, normal sort of amperage, the most common kind of plug…. But it will definitely explode whatever I might plug it into.
So there we are. I do not need ninety five of these taking up space in my house. And yet without any rhyme or reason to the combination of parameters, how am I ever meant to safely discard some of these?
There’s never been any effort to enforce a standard on mains transformers. The only thing that’s come close is USB (and here in the UK you can now buy a mains socket plate with an integrated transformer and USB sockets on it too – though personally I wouldn’t want a cheap transformer embedded in my wall). What you’re meant to do, I think, is keep them with the device and throw them away when the device breaks.
Requiring all new phones to work off standard connectors so that you didn’t need a charger for each one took the EU to enforce.
C7 in the UK is a 1970s thing, and was on the way out by the 1980s. I have some C5s for laptop power adaptors and such like, but anything that can fit them usually has a C13. (I don’t really do consumer electronics, though, so I’m talking about computers here; kitchen appliances just have an integrated power cable.)
(Bear in mind that when electricians from other countries visit the USA they tend to drink heavily. 110V is a terrible standard because of I²R heating, and stud construction doubles down on the problem.)
If you’re talking about DC, then yes, watts = volts × amps. With AC it’s more complicated; the wattage is usually based on root-mean-square voltage, which is a factor of sqrt(2) below peak voltage. This gets moderately complex quite quickly.
110v AC has the advantage that it is significantly less likely to kill you by direct means. Though it’s also the reason for another thing I hear folks from the UK find bizarre: our lack of electric kettles.