How to set the light switch (up or down)
It will be said in advance - UP. But is it? Let's figure it out!
As we already said, at the time of writing, there are no clear recommendations, but we can draw an analogy with other switching devices. For example, knife switches are structurally performed so that its blade contacts close when the lever-handle is turned up. Accordingly, when opening, the handle is lowered down, moving it from vertical to horizontal position.
Then in the event of an emergency, his contacts can be easily broken, for example, hanging on the lever with his whole body. This situation also provides protection against spontaneous switching on under its own weight, if for some reason the lever of the knife switch falls down or a foreign object falls on it - the contacts open. Therefore, when carrying out work on the line that is powered from it, unauthorized switching on cannot occur and this will not lead to electrical injuries.
However, in PUE 7 there is clause 4.1.9, which regulates the position of circuit breakers. Perhaps this is the only document in force today with such an indication.
All circuit breakers are structurally implemented so that when the flag is “up”, it is turned on, this is indicated by the signatures and indicators located on the front panel. When you turn off the machine, you always lower the flag down. Note that it turns off it is easier than cocking, which also facilitates shutdown in case of emergency. Accordingly, the power is usually supplied to the switching devices from above, and consumers are connected to the lower terminals - this rule also increases the safety when servicing electrical panels.
Even the old “AP” type assault rifles in square black cases have two buttons - the upper one turns on and the lower one disconnects the circuit, the same trend can be traced here.
From here we can derive a mnemonic rule:
Up - on, above there is tension. Down - off, no voltage down.
Remember that this is all true with proper installation and is a sign of good manners among electricians.
As for the light switches, in most cases they are mounted in the same way - into the gap of the phase conductor connected to the upper terminals, so that when you press the top of the key its contacts are closed and the light turns on.
But modern light switches are found in different designs, and in the form of keys familiar to everyone, and retro toggle switches, toggle switches of a more futuristic design and even touch screens, in which there is nothing to press at all.Therefore, their orientation in space can be determined by the manufacturer.
During installation, pay attention to the normal installation position the manufacturer has provided for - labels such as “On” and “Off”, “on” and “off”, or “I” and “O” can be applied.
If there is a backlight, then usually it is installed so that the indicator window is located on top.
Although there are models with a backlight window below.
Nevertheless, there is a horizontal arrangement of keys, sometimes it is provided for by the design, and sometimes it is done for the convenience of the user when installing the product at the desktop level.
The location of the light switch can also affect the convenience of turning it up or down. For example, it is believed that if the switch is mounted at the level of the hand down, it is easier to turn it on by pressing on its upper part. If the switch is at shoulder or eye level, it is easier to turn it on by pressing the bottom. But even in this case, we recommend setting it so that the light turns on “up”.
Also, do not forget about the old rotary levers, such models are still found in the catalogs of manufacturers of wiring accessories in retro style. Here, the vertical position of the lever usually says that the light is on.
Each person decides how to turn on the light - up or down, and determines how to set the light switch - high or low. The main thing is that in all rooms and rooms they should be installed identically and switched on in the same position. This is necessary so that when replacing the lamp or repairing the lamp, you can determine that it is turned off. If each time you work at a new facility, it is better to check for voltage in both positions before doing something.
We hope that now it has become clear to you what the correct position of the light switch to turn on and off should be. If you have something to supplement or you have not found your answer regarding this question - write in the comments under this article!