Which way should be "on" for a switch?
Most of us use switches every day in various forms. And although there are sometimes general norms in countries as to which direction is "on", there is variation between countries.
So when developing a product with a switch in it, which direction makes the most sense for "on", and why?
I'm not talking about other ways of showing that they will be on or off, I'm more talking about whether "on" is up, down, left, or right. Any research on this would be appreciated.
How about a pushbutton that is on when you press it, and when you press it again turns off? No direction needed, works everywhere... Just my $0.02...
@JeroenLandheer: Good point that this is another option. But that *is* another direction (inward). It's also a toggle, and the toggle characteristic could apply to switches that are pushed in other directions as well.
The image you embedded is a SPDT (single pole, double throw) switch having three states, both up and down can be on and middle is off. So...? (interesting)
@AlvinWong It was just an example of what I meant by a switch, so that people don't start thinking of networking switches.
@LarsH, A pushbutton doesn't have to have an inward state, optionally can have a light associated with it (even on the button itself), is used in all kind of forms (even on ballpoint pens) and works globally the same... Pushbuttons with lights behind it can also used to indicate state of a device or operation, alert conditions, etc. The thing is though, not every pushbutton is technically a 'switch' (as in switching from one state to another), you can look at your keyboard for an example of that :)
Intuitively I would go for up/right is ON. If I had to explain I would say that for slider, you would increase energy by going up. About the horizontal choice, LTR writing direction is influencing me (progress bars go from left to right as well).
Personally, and there's nothing to support this but my opinion, I prefer off to be down, on to be up. As a SF writer, I've always thought that if anything falls on a switch, brushes against it or it's hit in some other way, I'll want gravity on my side so that as a fail-safe the switch defaults to off in the direction of gravity. If there's no gravity, then on is outward, off is inward (because if it's stuck pressed, it's often better to be off). Generally, make the 'safe' position for the most stable state, whether on or off.
@JeroenLandheer: I generally agree with what you said. But the direction I was talking about wasn't the direction of *state* ('inward state'); rather it's the direction of *pushing*. The pushbutton you're talking about *does* have that direction.
Wonder if NASA has any guidelines for switch positions (operated in anything between 3-g and 0-g environments).
Symmetrical looking switches are confusing. Apart from that, I find the action "On" or "engaged", more close to actions "lift up" or "move forward to right" (popular reading direction).
Even if we just look at mplungjan and Guillaume86's comments we can see that intuition isn't enough here :-)
Most replies mention either `up` or `right` as most natural to reflect `on`. If the most important thing is that you know what the position means when you see the switch, I would therefore recommend you to place it diagonally where `upright` means `on`.
"Cultural question: which position is on, which is off?" http://en.wikipedia.org/wiki/Talk%3ALight_switch#Cultural_question:_which_position_is_on.2C_which_is_off.3F
Interesting to note that in switch panels (breaker boxes) if you mount the breaker on the left, ON is to the right (center), and if it is on the left, ON is to the left (center) at least in the US where the panel is mounted vertically - which matches the "power is in the middle, neutrals are on the outside so the ON is towards this power bar - such as the manual old fashion clasp type switch. (throw switch)
Funny you should ask this. A few months ago I built a hardware project in which I re-used the power switch (among other components). It is a rocker switch. Annoyingly, in the original device it was installed so that down was on. When I replaced the front panel with my own, I reversed it so that on is up. It is not only my preference, but consistent with other devices in the rack. It's easy to reverse that kind of switch. Just pop it out of the rectangular aperture, turn, and replace. http://www.kylheku.com/~kaz/smf-1/
It appears to be dependent on country or region, as Wikpedia states in the article Light Switch:
Up or down
The direction which represents "on" also varies by country. In the USA and Canada and Mexico and the rest of North America, it is usual for the "on" position of a toggle switch to be "up", whereas in many other countries such as the UK, Ireland, Australia, and in New Zealand it is "down." ... In countries prone to earthquakes, such as Japan, most switches are positioned sideways to prevent the switch from inadvertently being turned on or off by falling objects.
So there is really no direction globally true, if we believe in Wikipedia. Up or down or sideways differs by region. From what I learned in school (but I can't find a reference too now) is that vertical motion elecric switches use a metaphor for determin which is which. As an eyelid opens, the eye can see, meaning the switch is on. When the eyelid closes, we can't see, meaning the switch is off.
This metaphor works for electric switches, light switches and (modern) fuses.
But there is a problem. Electronics switches seems to have the metaphor crushed if you do image searches. You find all sorts of switches where Up is off and Down is on.
Or at least there are no consistency in direction
To conclude - be careful relying only on direction. An informative text or indicator light would certainly make it easier for your users.
Note that of your examples, only the ones with `ON` and `OFF` written on it can't trivially be mounted with either short side up. I think that's a big reason why the `on` state is represented as a simple vertical bar rather than a more elaborate `1`: you can mount it either side up and it will look the same to the casual observer.
Actually, it's just UK and Ireland that are reversed. In Australia and New Zealand, the light switches are the same as ours, it's the countries that are upside-down.
@MichaelKjörling true, but I often have trouble remembering which symbol represents "on", especially in the heat of troubleshooting when something in "|" acts "off", and I start thinking things like maybe "O" = "open"? etc.
I/O is the most miserable way to label a switch that I can imagine. Yes, I understand the binary interpretation now. But there have been so many times when I have been trying to get an engine to start when the logical interpretation has seemed to be: "I" means that something is closed, therefore nothing can pass through it, therefore "I" means off. "O" means that something is open, therefore things can pass through it, therefore "O" means on. This leads to frustration.
Please note that if you have 2 switches for the same function, you are not guaranteed to have the button state and power state always be consistent. For example: if you have a light switch at each end of a corridor, someone can turn on the light at switch A, and turn it off at switch B, leading to the light being in the same state as before, but both buttons being in the opposite state from before they were pressed.
Was wondering what "parts let us call 'em", of Japan, have their switches' directionaliy set, whether they'd be moving towards a more specific direction, and if so, at what pace if there isn't one standard for it in place already (what if for instance one part of the switch was uncomfortable to touch or sth, maybe it had a protruding light bulb a blind person could easily break if coming into contant with the switch at an extensive speed.
@KateKerhofs, this is what I originally had, parallelly-aligned versus cross-aligned. I would pick, from a purely psychological perspective... well, I couldn't decide. So, suggest some other way. Perhaps two equally functionin switches on each side with two lights, and then the reverse, with two walls. And then with the 4 lights and 8 switches there would still be plenty to decide. Some "derangements" set free would make a king's palpable toy switch.
@NateKerkhofs, yes but this is not the lovelyness of discreteness, or is it perhaps a live of sequences; maybe both, so, whatsoever, the world goes on and on and on. Don't forget we're trying our best to solve a "problem".
@jackmaddington I know that. The problem is "Which direction should be the on position of a switch?" And I am just trying to say that there are situations where the position of the switch and the state of the device the switch controls are not tightly coupled. In such a case, the direction of the on position of the switch can change depending on the sequence of actions performed on the system as a whole. My second floor hallway light has a switch on both floors to turn it on or off and the position of the switches is not linked. The bottom switch can be in either position with the light on.