The current prices for electricity make you think about saving where you did not even think about it earlier. For example, lighting on the stairs. It does not matter in a private or multi-storey house - you still need to pay. Previously, just left the light to burn. Today you are thinking about turning it off, but running up / down is also unhappy. It turns out there is a solution. To ensure that the light does not burn constantly, there are schemes for controlling lamps from several places. That is, one or more luminaires can be turned on and off from several points. Switches for this need special. They are called walk-through. Sometimes there are names "duplicating" or "flip-flops". All this is one type of electrical equipment. Differ from the usual large number of contacts. Accordingly, the circuit of connecting the pass-through switch is more complicated. Nevertheless, you can sort it out.
How the passing switch looks and works
If we talk about the front side, then the only difference: a barely noticeable arrow on the key up and down.
If we talk about the electrical circuit, everything is also simple: in the usual switches only two contacts, in the passageways (also called throw-over) three contacts, two of which are common. In the scheme there are always two or more such devices, here with the help of these common wires they are switched.
The principle of operation is simple. By changing the position of the key, the input is connected to one of the outputs. That is, these devices have only two working positions:
- the input is connected to output 1;
- the input is connected to output 2.
There are no other intermediate provisions. Thanks to this, everything works. Since the contact switches from one position to another, electricians believe that it is more correct to call them "switches". So the pass-through switch is also this device.
To not rely on the presence or absence of arrows on the keys, you need to inspect the contact part. On branded products should be put a scheme that allows you to understand what kind of equipment you have in your hands. It is definitely on the products of the companies Lezard (Lezard), Legrand (Legrand), Viko (Vico). On Chinese copies, they are often absent.
If there is no such circuit, look at the terminals (copper contacts in the holes): there must be three. But not always on inexpensive copies of the terminal that stands alone is the entrance. Often they are confused. To find where the common contact is located, you need to call contacts between each other at different positions of the key. To do this is necessary, otherwise nothing will work, and the device itself can burn.
You will need a tester or multimeter. If there is a multimeter, translate it into a sound mode - it squeaks when there is a contact. If there is an arrow tester, call for a short circuit. Place the probe on one of the pins, find with which of the two it is ringing (the device is ticking or the arrow is showing KZ - it is deflected to the right until it stops). Do not change the position of the probes, change the position of the key. If the fault has disappeared, one of these two is common. Now it remains to verify which. Without switching the key, move one of the probes to another contact. If there is a fault, then the contact from which the probe is not moving and there is a common (this is the input).
It may become clearer if you watch a video on how to find the input (common contact) for a loop-through switch.
How to connect the hob is written here, and about installing and turning on the water heater - in this article.
Scheme for connecting a pass-through switch from two places
This scheme is convenient in a two-story house on the stairs, in the passage room, in a long corridor. You can apply it in the bedroom - turn off the top light at the entrance and near the bed (how many times did you have to get up to turn it on / off?).
Zero and earth (if any) are fired immediately on the lamp. The phase is fed to the output of the first switch, the input of the second is wound onto the free wire of the luminaire, the outputs of the two devices are connected together.
Looking at this diagram, it is easy to understand how the loop switch works. In that position in the figure, the lamp is switched on. By pressing a key on any of the devices, the circuit is torn. Similarly, when the position is turned off, by switching any of them to another position, we will close the circuit through one of the jumpers and the lamp will light up.
To make it clearer what and with what to connect, how to lay wires, we will result some images.
If we talk about the room, then you need to lay the wires roughly like in the photo below. By modern rules, they should all be at a distance of 15 cm from the ceiling. They can be stacked in mounting boxes or trays, the ends of the wires are put into the mounting boxes. This is convenient: if necessary, you can replace the punched wire. Also, according to the latest standards, all connections take place only in the installation boxes and with the help of contactors. If you do twists, it is better to dissolve them, and top them with a piece of electrical tape.
The return line of the lamp is connected to the output of the second switch. White indicates the wires that connect the outputs of both devices.
How to connect everything in the terminal box is told in the video.
How to connect the chandelier yourself here.
3 point scheme
To be able to turn on / off the light from three places, it is necessary to buy a cross (cross) switch to the two switches. From the previously described it is distinguished by the presence of two inputs and two outputs. He switches a couple of contacts at once. As everything should be organized, look at the picture. If you understand what is above, to understand this simple.
How to assemble such a scheme? Here is the procedure:
- A zero (and ground, if any) is wound directly on the lamp.
- The phase is connected to the input of one of the pass-through switches (with three inputs).
- The second input is applied to the free wire of the lamp.
- Two outputs of one three-pin device are set to the input of a cross switch (with four inputs).
- The two outputs of the second three-pin device are connected to the second pair of switch contacts with four inputs.
The same circuit, but in a different perspective - where to connect the wires on the housings.
But about so to plant on the premises.
If you need a scheme for four, five or more points, it differs only in the number of cross switches (four inputs / outputs). Switches (with three inputs / outputs) are always in any circuit two - at the very beginning and at the very end of the circuit. All other elements are cross devices.
Remove one "crossroads", get a control scheme of four points. Add more - there will already be a scheme for 6 management places.
To finally put everything in the head, look at this video.
On the rules for connecting the wires in the junction box, read here.
Two-key through-hole switch: wiring diagram
In order to control the illumination of two lamps (or groups of lamps) from several places from one switch, there are two-key pass-through switches. They have six contacts. If necessary, the common wires are found on the same principle as in a conventional device of this type, only a greater number of wires will need to be called.
The wiring diagram of the 2-way key switch differs only in that the wires will be larger: the phase must be fed to both inputs of the first switch, as well as from the two inputs of the second one, it must go to two lamps (or two groups of lamps, if it is a multi-hood chandelier ).
If it is necessary to organize the control of two light sources of three or more points, you will have to put two cross switches at each point: there are simply no two cross key switches. In this case, one pair of contacts is started on one crossroad, the second - on the other. And further, if necessary, they join together. At the last in the chain, a two-key transfer switch connects the outputs of both crossroads.
If you think about it, everything is not so complicated, and the circuit for connecting a two-point pass-through switch, so simple at all. Only a lot of wires ...