Why do circuit breakers go up for on and down for off?

Why do circuit breakers go up for on and down for off? Would they work installed upside down?

It goes back to the early days of electricity, when knife switches were used in distribution boards. They had no spring to hold them in place, so gravity would pull them down and it took an intentional action to move them up. It was considered that meant it was safer for down to be off and up to be on.

That I did not know. And I have a degree in electrical engineering!

"That I did not know. And I have a degree in electrical engineering!"

But in a domestic setting they replaced fuses, which didn't have a switch. In a domestic setting, lightswitches and switches for appliances are all down for on. So are car windscreen wiper switches except for Renaults which are up! I've had this Renault for 5 years and still move it the wrong way. There are some things in life which should always be one way. Down or right is always more, it's the way we read a book. Accelerator on the right, brake on the left. Volume on a stereo is louder to the right and quieter to the left. Bass and treble the same. You tighten a screw by turning it to the right. Linux and Mac correctly have ok on the right and cancel on the left. Microsoft got it wrong. Despite using Windows every day (I'll touch a Linux or Mac machine about once every 6 months), I'm always pressing the wrong button, because I assume the button on the right will be the affirmative action, since that's the way it is on most everyday things.

As for knife switches, I always mount those horizontally.

I tighten most screws by turning to the left.

You must be looking at the top of the screw head instead of the bottom like you should.

Maybe you're shorter than me and all screws are above your head?

I wonder if you're as thick as the PE teacher I had at school. He thought clockwise round the gym hall was by looking at the ceiling.

Of course they would. Its interesting, since many breakers use just a button that comes out to disconnect. Its a bit like the history of on off switches. Being an oldish house, the light switched are down for on, but in many pieces of electronic mains equipment it is the other way by around. This has something to do with shock hazard. IE if you do get a shock and are rendered unconscious, then as you fall, you will push the switch down, however in the real world it probably makes no difference whatsoever. Brian

Because that's the 'right' way for switches to work! :-)

If there's a mechanical failure of some sort in the mechanism it falls down into the off position.

Professional test gear and such nearly always has up for on (or at least it used to when I worked in that field). Also up for on is the norm in many countries.

I'm sure the modern ones will work any way around you wanted. If you don't like it simply do a head stand before you change them.

My main question, however is why are some breakers so sensitive they trip more often than others? I think they are way too complex now with earth leakage as well as just looking for overloads. Brian

Too much health and softy nowadays. But they always get it wrong. For example they fuss about silly little things in cars, but allow 3 door cars where the rear passengers can't get out in a crash. And no mudguards so on a wet motorway nobody can see where they're going.

In America, they are crazy about GFCI (their name for ELCB) to compensate for their stupid plugs and sockets. The sockets have no switch, and the plugs have no sleeves on the pins, so you're always exposing live (sorry, hot, yes they really call it that) and neutral to your fingers.

Which never happens. Much more likely is confusion over which way it operates. The majority of everything in the world is down or right for more of it.

Always buy the least sensitive ones. I had a 32A breaker in my house (where did that extra 2 amps come from?) which tripped every time I switched on 7 computers at once. The inrush current to charge the caps I guess. I changed it to a 30A fuse and it's fine. The total load even when the computers are running flat out (which they're not at startup) is 16A. Similar thing at work (a school). 20 computers on a breaker (can't remember the rating). If they all pressed the power button around the same time (which happens in a class when the teacher tells you to start the computer), it tripped. Odd, as that wouldn't invoke the charging of the bulk caps, maybe the output caps? I told the electrician who'd just installed it to make it a less sensitive one. He refused, because the stupid regulations state in a school full of kids, they have to trip faster.... than for the same kids at home?! So I bought less sensitive ones on Ebay, changed them when nobody was looking, then sold the old ones.

I used to have a problem with random tripping of the whole house RCD. Removing that and replacing all the previously RCD protected MCBs with RCBOs, split any base leakage (mainly filters on power supplies of a lot of electronic items) across separate circuits and we have not had a single false trip since.

Anyway, if you think that adding earth leakage detection to overcurrent protection is too much, wait for the AFDDs (Arc Fault Detection Devices), which are RCBOs, plus a microprocessor that monitors the circuit and analyses the waveform for changes that indicate arcing in a loose terminal, but *shouldn't* trip on the arcing of a motor's brushes!

We once owned a right-hand drive Ford Taunus Mk 5 (it was built as a right-hand drive for the first owner, stationed with the British Army in Germany) - although when it was imported to the UK, the Taunus badge was replaced by a Cortina one and it was registered as a Cortina.

The only "obvious" sign that it was not a UK Cortina, was that the heated rear screen switch and the hazard warning light switch (the only two rocker-switches) operated "upside-down".

Yes. I always understood that down for OFF was safer, because in an emergency it was a more-natural human action to swipe a switch downwards.

That's the trouble with safety devices, they're too stupid to know why there's current going to earth. Just like a burglar alarm which gets upset with a sparrow hitting the window. It took 5 calls to the police in the middle of the night before they got fed up and my neighbour was forced to remove his alarm.

It would have been easier to remove the ELCB altogether. And since when did it join the gay community and get renamed to RCD? What next, RCDLGBTQ+?

Yeah right. Fuses for me. They break on an overload and nothing else. No girly shit here. They're to stop a fire. For what other reason would you have a device shut off power?

Nothing protects you from live in one hand and neutral in the other. It doesn't matter how much pansy shit you install, there's always a danger. Just live with it.

Was the DVLA really so pathetic it couldn't be registered as a Taunus? Is that a rude word in English or something?

I can't remember which way up those usually are, since I've not had a car with a rocker switch for either of those for years. Which way are you calling "upside down"?