How to connect two switches for two light bulbs: scheme, instructions, recommendations
Home electrics are among the types of work that most of us prefer to trust professionals. And, nevertheless, to replace the failed electrical outlet or a simple single-circuit lamp, many owners still decide on their own. But the task of how to connect a two-button switch for two light bulbs, raises some questions - and the switch itself with the “extra” contact, and again the “extra” wire in the mounting opening. And the abundance of connections in the split box simply leads to shock. We will try to dispel some of the fears and doubts. Moreover, two or even three-circuit lamps recently are not an exception, but rather a rule.
A separate conversation - dacha construction. What kind of lighting schemes for gazebos and adjoining territories are not thought up by the owners of the hacienda.How to connect two switches for two bulbs so that, depending on the need to increase or decrease the level of illumination?
A few words about electrical current
Without "loading" the theory and complex physical concepts, we recall the elementary basics of electricians. Household electrical network has a voltage of 220 V, the type of current is variable. What does it mean? One of the contacts, “phase”, has a constantly changing potential from “+” to “-” (50 cycles per second), and the other “zero” serves as a kind of accumulator, allowing electrons to accumulate in excess, then flow back.
Each lamp has two contacts: ground and center. In order for our lighting device to start working, zero and a phase must be connected to these two contacts. Moreover, in the case of alternating current and ordinary household lamp polarity does not play any role.
But the location of the "zero" and "phases" is still necessary to know. There is a special device - "probe", with which it is determined which of the wires is phase. This must be borne in mind for the correct inclusion in the circuit of the disconnecting device - the switch.He must break the "phase", such are the security requirements.
Connection diagram of the simplest luminaire
Using the example of the simplest single luminaire, “Illich’s light bulb,” we consider the main elements of an electrical circuit.
In any apartment wiring, as a rule, is laid in the wall around the perimeter at a distance of about 10-15 cm from the ceiling. This is the highway. It is equipped with junction boxes. They are needed in order to "crashing" into the trunk cable to power the outlet or switch with a lamp.
Consider the wiring diagram of the wires in the junction box. Down from it goes the cable to the switch, up - to the lamp, to the left and to the right - the trunk cable. In fact, this is, of course, a convention, the order in which the wires are inserted into the box is determined only on the basis of considerations of expediency.
Zero wire with it is simple. It branches off directly from the highway and goes straight to the lamp. The situation with the phase wire is not much more complicated, it also goes to the lighting device, but only through the switch. That's all the wisdom.
The usual one-key switch has two contacts behind for connection of wires. In this case, the polarity is not important.And how to connect the chandelier to the two switches? Is the task much more complicated?
Double-circuit chandelier - wiring diagram
For a more rational use of electricity in apartments, lamps with two or even more circuits are often used. In essence, this is the same as connecting two switches for two light bulbs. The scheme can be the following: one switch key lights two lamps in a chandelier of five, the second key turns on the remaining lamps. The scheme is not complicated, but, nevertheless, allows you to use three options for lighting in the room:
- weak light - the first key - two lamps;
- middle light - the second key - three lamps;
- strong light - both keys - all five lamps.
How to connect a switch with two keys, shown in the diagram. Zero wire straight from the junction box divorced to the lamps. “Zero” wiring for individual lamps, as a rule, has already been done at the lighting factory, and the electrician only connects “zero” to the black or blue terminal.
"Phase" is sent to a double switch, from which come two wires: for the first and second circuits.
Replacing the two-button switch with two single-button
If necessary, one double switch can be safely replaced by two single. The only thing needed for this is a short jumper wire between the receiving terminals.
How to connect two switches for two light bulbs, the diagram is shown in the figure. It shows how simple, without special tricks, the two-button switch is replaced by two single-key ones.
Such a scheme can be justified not only by the lack of a two-button switch in the household. Sometimes lighting, say, parking for a car in a country house, is well done to be controlled from different points: from the exit door of the house and from the device mounted on the gate pillar.
And here we smoothly proceed to the next topic. In the same way as connecting two switches to two bulbs, but much more practical, you can use pass-through switches.
What is a pass-through switch?
What are these devices and where do they apply? In addition to the considered option, how to connect two switches for two light bulbs, there is a better possibility: using two switches located at different points, to control one lighting device.
The device of standard household switches, as a rule, is of the same type.There are two contacts - fixed, fixed on the device case and mobile, mounted on the rocker arm. The yoke changes its position under the action of the key. The device, respectively, has two positions "On" and "Off".
The switch through passage (it would be more correct to call it “switch”) does not have the “Off” position. As can be seen from the figure, it has the provisions:
- 1 line included;
- 2 line included.
What are loop-through switches used for?
One option for using walk-through switches is the same as the one previously discussed: a lamp or a spotlight illuminating the parking of a private household. The use of walk-through devices will allow you to turn on the lighting of the platform from one point, say from the corridor of the garden house, and turn it off from the other. For example, just before departure, a switch mounted on the entrance gate. Moreover, the on-off order can be absolutely any.
The second option is a long corridor free from natural light. The light turns on at the beginning and turns off at the end or vice versa. Conveniently? Of course. So before you connect two switches for two light bulbs, it is worth a good deal to think about whether to replace this circuit with the option with pass-through switches.
Corridor lighting scheme using two pass-through switches
Externally, loop-through switches are almost indistinguishable from ordinary ones. Only on the reverse side instead of two there are three terminals:
- L № 1;
- L No. 2;
How to connect the lamp to two switches correctly, shown in the diagram.
"Zero" on the lamp comes through the blue wire. Phase - in red. From the figure it is clearly seen that the power to the lamp will come only if both switches are in the same positions. Changing the position of the key on any of the devices will cause the circuit to break and the power supply to the lighting device to stop. Well, and after the light is turned off, clicking any of the switches will close the circuit again, and our corridor will light up again.
On staircases, in long corridors or tunnels, instead of expensive infrared sensors, you can simply connect two pass-through switches.
Installation security measures
Here is a set of some standard rules to avoid trouble when installing lighting fixtures:
- The switch can not be set to "zero", they should always break the "phase".Only in this case, the switch in the "off" position allows any repair work with the lamp, up to its replacement, without de-energizing the whole house.
- When performing the connection of wires in the splitting junction box, in no case should aluminum and copper wires be interconnected. Metals with different potentials form a galvanic couple, contact with time will weaken, will begin to “spark”. Sometimes it causes fires.
- Before starting work, you should stock up with a probe to determine the phase wire and, just in case, thick rubber gloves.
- You should not stick open wiring (even in double insulation, even in triple, it does not matter) with paper wallpaper, other combustible finishing materials.
- Do not use used wiring. It is not known how it was subjected to loads in the past, and it is impossible to check the condition of each core inside the sheath throughout.
In order not to be confused with the installation of electrical wiring, it is better to buy wires with different color of wires. The phase is usually connected to a white or red wire, zero to blue or black, while yellow, green or yellow-green are used for grounding.
When laying wiring under a layer of plaster is to keep the layout of the wires. This may be needed in the future. The easiest way is to take a picture of the wiring that has not been immured yet, by applying chalk or a marker to the wall, ceiling, corners, window apertures and other landmarks directly with chalk or a marker.
Calculations of the cross section of the wire should not be made at a minimum, it is better to give some margin. Then the head will not hurt when buying a new large plasma panel or installing a dishwasher in the kitchen, and in the country, if necessary, you can safely connect a household welding machine or a power saw to the network.