How to wire a dimmer switch in 10 steps
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When you’ve got a multi-bulb light fitting, chandelier, or downlights, it’s not always possible to go down the smart-bulb route to be able to control their brightness and sometimes, their colour – whether it’s due to lack of compatibility, or cost. This was the case for me in my lounge, where I’d found the most perfect light fittings – but there was a catch, they required 6 bulbs per fitting.
For someone whose home is filled with smart gadgets – hoovers, lawnmowers, lights, speakers, tv etc., buying 12 smart bulbs just for one room didn’t really seem like an economical option. 12 standard LED bulbs also let off a LOT of light – blinding in fact!
- Find your favourite living room lighting ideas.
To remedy this, I looked into swapping the switch to a dimmer. A straightforward DIY, and one that will save me over a hundred pounds vs buying smart bulbs. Full disclosure, I am not an electrician, nor have any electrical qualifications, all knowledge has been gained through research and trial and error and hope to pass this knowledge onto you, so you too can try things for yourself.
The most important thing to note here, is ALWAYS turn off the electrics at the fuse box before touching wiring, light fittings or their switches.
Having wired in all the lights in my house, I knew wiring a switch wouldn’t be that much more complicated, especially if it’s a multi-light switch or if there are multiple switches for the same lights. The key is to ensure you know which wires go where, so taking a photo of the current wire setup and labelling each wire with a bit of masking tape and a pen can make the process a lot easier for you.
What you’ll need for this task:
- A small flat head screwdriver to loosen and tighten the wire clamps
- A larger screwdriver to remove and secure the fittings to the wall
- Tape or blu tack to remove any decorative screw covers
- An AC non-contact voltage detector – available on Amazon
- Wire strippers (not always necessary)
- Masking tape and a pen to label wires for ease
- Your phone to take photos of the setup (or you could draw this out)
- Dimmable bulbs available on Amazon
(Image credit: Jasmine Gurney)
How do you wire a dimmer switch?
Whether you’re switching to a shiny new fitting, switching from a standard on/off switch to a dimmer, re-wiring two lights into a single switch or splitting two lights into separate switches, the process is essentially the same. Provided you copy the existing working setup and label the wires before disconnecting, there’s not much room for error!
Of course, this does come with another safety warning to turn the fuse off before touching any electrics, but also, if you go wrong, see any sparks, or just don’t want to give it a go yourself, get in a professional electrician to help.
1. Turn off the power on the main circuit switchboard
Turn off the light ring on the main circuit switchboard/fusebox and check they’ve been turned off by flicking the switch on and off.
(Image credit: Jasmine Gurney)
2. Remove the screw covers
Using tape or blu tack, remove the decorative screw covers of the existing fitting and use your larger screwdriver to undo the two screws and carefully pull the fitting away from the wall. If you did not remove this fitting when decorating, you may need to score the paint around the edge of the fitting with a Stanley blade to prevent the fitting lifting any paint.
(Image credit: Jasmine Gurney)
3. Double check the wires are not live
Using your voltage detector, triple check that the wires are not live. If they still are, go back to the fuse box and shut off the main power (everything!) to be safe. You don’t want to be thrown across the room having touched 240 volts!
(Image credit: Jasmine Gurney)
Draw out your wire setup
Take a photo or draw out the layout of the current wire setup. You will have a 2-core cable (or multiple) from the wall with a yellow and green (earth) wire earthed inside the wall box, a brown (live) wire going into the switch and a blue (neutral) wire. This is connecting the switch to the fuse box.
There will also be another brown wire, or a blue wire with a brown sleeve coming out of the switch into the wall. This is a ‘switched live’ wire connecting the light to the switch. If you live in an older property, the wires may be black and red, red being Live and black being the Neutral.
The live wire brings the power supply to the switch. The neutral wire takes power to the light and the switch sits on the live wire to complete/break the circuit. If your setup differs from a standard 2-wire system, it could be a 3-wire lighting system which usually includes an additional neutral wire that goes into the light via a connector block as per the poorly drawn diagram below.
(Image credit: Jasmine Gurney)
5. Identify and tag your wires
You will notice that the brown wires from the wall goes into the COM port on the existing switch and the blue with a brown sleeve switched live wire will be going into the numbered L ports. (To make things even more confusing, the switched live wires can sometimes be completely brown.) You may also have a separate wire connecting the two switches via the COM port on a multi switch fitting to connect the circuit. For mine, the wire was a little too short, so I had to trim some spare wire I had to ensure it reached between the COM ports.
Your new light fitting should come with an instruction leaflet to help you identify which wires go where. Using masking tape and a pen, label which wires went into which port before you disconnect them. It can get very confusing when there’s more than one switch and lots of brown wires floating around!
6. Release the wires from the switch fitting
Using your small flat head screwdriver, loosen the screws clamping down the wires, releasing them from the switch fitting.
(Image credit: Jasmine Gurney)
7. Re-wire the new switch
Using your diagram/ photo, it’s time to re-wire the new switch, stripping the wire if needed to ensure better contact in the port or if the copper wires is damaged or crimped. You will notice in the setup above that the COM ports are labelled with a wavy line with an arrow through it instead, but this is where the Live wires from the electrical circuit go into.
Again, the switched live go into the L ports. The switch above is a dual light fitting, meaning it controls two lights, hence the jumble of live wires.
If you have one switch that controls multiple lights (rather than multiple switches, each controlling one light each), you will need to use the L2 ports which would control the second light with the same switch.
8. Set the brightness level
Your dimmer switch will also have a dim level control screw to adjust how dim (minimum dimness) or how bright (maximum brightness) you want the lights to go when turning the dial. Set this to whatever setting you like. Give each of the wires a little tug to ensure they can’t easily come loose.
9. Add your dimmable bulbs and check the wiring
Add your dimmable bulbs to the light fitting, then it’s time to check the wiring. Go and turn the fuse back on and return to the switch. Without touching any of the wires, turn on the switch on the front, adjust the brightness and ensure all is okay. It is normal for the unit to hum quietly when dimmed, however if the humming or buzzing is loud or there is any crackling sound, you will need to turn the fuse off again and check the wiring setup. A loud hum could also indicate that the bulbs you are using are not in fact dimmable. They will usually say DIM on them if they are dimmable.
(Image credit: Jasmine Gurney)
10. Mount your new fitting
If all works, it’s time to mount the new fitting on the wall, using the screws it comes with to fix it to the existing box unit. Put the decorative caps back on and touch up any paint that may have been lifted when removing the original switch. You can now enjoy your new dimmable lights!
- Living room wall lighting ideas to brighten up your home.
(Image credit: Jasmine Gurney)
How to Fit a Dimmer Switch
How to fit a dimmer switch; advice and wiring instructions for fitting or installing a dimmer light switch and swapping an existing light switch for a dimmer switch. Understand how to safely wire in a dimmer switch and find out about the regulations that cover this sort of project.
Adding a dimmer switch to the lighting in a room can have a dramatic effect on the overall ambience of a room, allowing you to lower the lighting levels to create a much more relaxed environment.
In this DIY guide we look at how to fit a dimmer switch in place of a standard light switch.
Regulations for Fitting Dimmer Switches
In accordance to the Building Regulations and the BS 7671 wiring regulations, if you are simply exchanging an existing standard 1 or 2 gang light switch for a dimmer switch then this is entirely possible to do on a DIY basis, as long as you have the knowledge to do so.
However, if it is to be a newly installed switch where all wires and cabling needs to be run from scratch then this is not possible to do as a DIY’er and can only be done by a Part P registered electrician with the knowledge and skill to do the work correctly, test it fully and then issue a minor works certificate.
Failure to do this correctly can cause issues when trying to sell your home and can even invalidate your home insurance!
One thing to be aware of is that back quite a few years ago the wire colours that were traditionally used were changed to harmonise with those used in Europe so you may find you have different coloured wires in your home. For more information on this see our wire colours project here.
For more information on staying safe when working around electricity, see our electrical safety project here.
What is a Dimmer Switch?
A dimmer switch is a type of light switch that allows you to control the amount of electricity that flows to the lights it controls, which, when turned down dims them or when turned up brightens them, manually enabling you to set the light level in a room.
Traditionally, dimmer switches used a variable resistor that essentially restricts the flow of electricity by converting it to heat. This not only caused the resistor to get hot but also, this was a massive waste of electricity.
Today, modern dimmer switches are much more efficient and instead of using a resistor, essentially turns the light on and off very rapidly every second. As both UK and US electricity is AC (alternating current) it turns from positive to negative every cycle.
Modern dimmer switches use this cycle to determine when to turn the light off. At the point that the switch from positive to negative happens there will be zero voltage and this is when the switch cuts the power.
When it turns it back on depends on the position of the dimmer. If it’s set to a bright setting it turns the power back on very quickly, but if set to a dim setting, it will wait a little before turning it back on again. These are known as phase cutting dimmer switches.
Standard single gang dimmer switch
Types of Dimmer Switch
There are numerous different types of modern dimmer switch, but essentially they can be broken down into 2 main types:
- Leading Edge
- Training Edge
The names refer to the way in which they control light levels. As mentioned above, modern dimmer switches work by rapidly cutting the supply of electricity to the light half way through it’s cycle when the current hits zero.
A leading edge dimmer cuts the front off of the second part of the wave cycle, where as a trailing edge dimmer cuts the second part of a waves cycle.
Both of these types of dimmer have their own distinct characteristics, but on the whole, trailing edge dimmers are seen as slightly better as they have a smoother operation and tend to make much less noise.
Aside from the main differences in how they operate, dimmer switches are also available in several different operation:
- Single-pole: Controls 1 set of lights from a single switch in a single location
- 3-way dimmer: Allows for the control of 1 or a series of lights from 2 different switches
- 4-way dimmer: Allows for the control of 1 or a series of lights from 3 different switches
- Smart dimmers: Use smart automation technology and wifi to enable you to control a single or set of lights using an app
Smart dimmer switch
Can you put a Dimmer Switch on any Light Switch?
Today, pretty much all light fixtures are compatible with a dimmer switch and can be swapped like-for-like. However, the main issues come with the type of light bulb they will be controlling.
Most incandescent and halogen bulbs are compatible with dimmers, but generally CFL’s (or compact fluorescent lights) or those that are controlled by a transformer generally don’t, unless they are made specifically for use with dimmer switches.
When it comes to LED’s there are 2 types, those that are compatible with dimmer switches and those that aren’t. This should be stated on the bulbs packaging.
Dimmable LED bulb
Tools and Materials for Fitting a Dimmer Switch
To fit a dimmer switch in place of a standard light switch you will need the following tools and materials:
- Small plat blade screwdriver
- Philips screwdriver
- Dimmer switch of your choice
- Brown/red tape – to mark switched live if not already marked
How to Fit a Dimmer Switch
As we have now looked at what a dimmer switch is and how it works, it’s now time to see how they are fitted.
For the purpose of this project we will be swapping and existing 1 gang 1 way switch for a similar 1 gang 1 way dimmer switch.
Step 1 – Isolate Circuit
The very first job to do before doing anything else is to isolate the circuit you will be working on by turning off the MCB/RCD in your consumer unit or pulling out the fuse if you have a fuse box.
Isolating circuit in consumer unit
Step 2 – Unscrew Switch Faceplate
Once the power to the circuit and switch are isolated, the next job is to use a flat blade screwdriver to unscrew the 2 screws on the front of the faceplate.
Once done, put the 2 screws to one side and pull the faceplate away and turn it to reveal the internals on the rear of the face.
Rear of 1 way switch with wiring
Step 3 – Disconnect Wiring From Switch
On the rear you will most likely find a brown and blue or red and black wire connected to the switch. Red (live) and black (neutral) are old wire colours and brown (live) and blue (neutral) are new colours. The blue/black neutral should also have a brown/red sleeve or piece of tape wrapped around it to indicate that it’s the switched live.
If you have a metal face plate for your switch there should also be a green and yellow earth wire to a small terminal on this. If not then it should be connected to the metal box in the wall called a pattress box. If the pattress box is plastic then it should be screwed into the earth terminal somewhere inside.
Before removing anything, first take a picture of the back of the switch so you know where all the wires go. The brown live should be in COM and the blue neutral/switched live should be in L1.
To release each wire on the switch, use your flat blade screwdriver to loosen the small screw in each terminal and then pull the wires free. If the earth is also fixed to the faceplate, unscrew this, if attached to the pattress box leave it where it is.
For more detail on how light switches are wired, see our lights and switches project here.
If you have more than a brown/red and blue/black wire in your switch, then you are involved in two or three way lighting. This can get quite complicated in terms of what goes where so refer to our lights and switches project linked to above for more help with this.
Loosen wires in rear of switch faceplate
Step 4 – Connect new Dimmer Switch
With the old switch out of the way, take your new dimmer switch and connect the wires in the same place as the old one; brown live to COM and blue switched live to L1
If the new dimmer switch has a metal faceplate then you will also need to connect the earth to the earth terminal on the faceplate.
Terminals on rear of dimmer switch faceplate
Step 5 – Screw Faceplate Back on
Once all of the wires are connected to the correct terminals, turn the faceplate back around and position it back over the pattress box.
To get it to sit flat, you may need to give it a little wiggle so that the wires find their own natural resting place.
Once correctly positioned, pop each screw through each hole and then screw it up tight, ensuring that it’s level.
Step 6 – Test Switch
Once all is back in place and screwed in to position, go back to the consumer unit and turn the circuit back on.
Go back to the switch and turn the dimmer dial until you hear a click, this means it’s turned on. Turn the dial slowly around and you should see the light slowly get brighter.
Your job is now done, good work!
Fitting a dimmer switch in place of an existing standard light switch is a fairly easy and straight forward job as long as you know what you are doing.
If you are in the slightest bit unsure on what to do you should get a professional electrician in.
All project content written and produced by Mike Edwards, founder of DIY Doctor and industry expert in building technology.
how to control lighting from several places – Blog – EKF
One of the most common types of light switches is a mechanical rocker switch with one, two or three keys.
Switch buttons are also called backstage or rocker arms.
Switch simply turns the light on and off. Double Throw Switches are “walk-through switches” that look like regular switches and are mounted in pairs. They are used to control lighting from two places, usually at the top and bottom of stairs. You can install a third – intermediate switch to switch the light on and off from three places.
The flush-mounted switches can be mounted in a standard flush-mounted wall box (flush-mounted) or on the wall surface in a special plastic surface-mounted box, if available for the specific product range.
The surface-mounted switches are mounted directly on the wall without an additional mounting box.
In addition to simply switching on and off, the switch-regulator (dimmer or dimmer) will change the light intensity according to your desire. On some models, one round knob acts as a switch and as a regulator at the same time. For others, keyboards (buttons), one key is a switch, and the other is a dimmer.
How to choose a switch
The most common models are universal colors – white and cream, they are suitable for any interior. If you want to make the switch a design element, then you can choose unique shades of mechanisms and frames. The latter are made of plastic, glass, aluminum.
Illuminated switches are easy to find in the dark – their mechanism contains an LED or low-power neon micro-lamp. To avoid flickering (flashing) of LED or compact fluorescent lighting lamps when switched off, it is generally not recommended to use them with such switches. However, there are ways to fix this problem. We will talk about them below.
- Simple switch
Inspect the switch. It has two insulated wires.
The simple switch has only L and 1 terminals. The terminal arrangement of these products is similar to that of the female terminals. The phase wire (check with an indicator screwdriver) is connected to the L terminal. “Input”, often duplicated by an arrow pointing to the center of the switch. The wire going to the load – the lamp, is connected to terminal 1. “Output”, often duplicated by an arrow pointing from the center of the switch.
The mechanism or support of the product is usually marked with a top (top), so that when assembling the key takes the correct position. The device will work upside down, but the correct position of the key allows you to know whether the switch is on or not, even if the light bulb is burned out.
Sometimes you will find a light switch that has two wires connected to it and works like a single switch but has three terminals. This is a bi-directional device that is connected for single-line use, i.e. it is used in one direction, which is completely safe.
- Pass-through switch (two-way switch)
A two way switch will have at least one conductor in each of its three terminals. Depending on the position of the key, the L terminal is connected to either terminal (1) or terminal (2). For the correct connection of the new mechanism, note down the matching of the conductors on the old switch before disconnecting it. Another simple method is to disconnect one wire at a time and connect it to the corresponding terminal of the new switch before disconnecting the next wire.
- Two-gang switches
A two-gang or double switch is used to control two lights or two groups of lights. There are two options for its implementation.
Usually electrical elements are combined in one mechanism. In some series, a two-key device is a combination of two independent mechanisms. In this case, it is necessary to connect the terminals for connecting the phase wire with an additional jumper.
- Dimmer instead of rocker switch
Inspect the key switch to determine the type of connection. The switch-regulator (dimmer) must match this connection.
Be careful when choosing a dimmer!
Check that it matches your luminaire – power and load types: incandescent lamps, halogen lamps with electronic or ferromagnetic transformer, dimmable LED or fluorescent lamps. When choosing a dimmer power, you need to remember that the passport value is indicated for a single installation in a concrete or brick wall. When the dimmer is installed in thin-walled drywall partitions, etc., its power is reduced by about 15% due to poor heat dissipation.
Do not use the dimmer with conventional (non-dimmable) LED or fluorescent lamps!
Illuminated Switches in Energy Saving Lighting Systems
With the advent of compact fluorescent and later LED lighting, many homeowners have encountered the problem of flickering off when using illuminated switches. The fact is that when the contacts of the device are open, a very small current (0.15-0. 3 mA) continues to flow through the backlight element – an LED or a neon lamp. It causes the backlight element to glow, and also gradually charges the capacitor – an integral part of the circuitry of any energy-saving fluorescent or LED lamp. When the capacitor is charged, the voltage across it grows and at a certain moment reaches a level sufficient to start the main circuit of the lamp. The energy stored in the capacitor is only enough for a short flash. It is discharged, and the process is repeated again.
This reduces the life of the lamp, and it is uncomfortable to be in a room with such a lamp. To solve this problem, it is necessary to exclude the charge of the lamp capacitor when the backlight element is lit. This can be done in two ways:
- connect the lamp through an intermediate relay,
- to replace such a switch with a light switch by connecting its backlight element in a non-standard way.
- Use of intermediate relay
10-16 A electromagnetic relay should be connected so that the illuminated switch controls the relay coil (terminals A1, A2), and the relay power contacts supply power to the lighting lamp when the switch is turned on.
Modern relays are quite compact, they can be easily placed in a luminaire body or in a chandelier under a decorative cap that covers the ceiling mount and mounting terminals.
- Replacing a switch with a two-way switch
If there is a neutral conductor (neutral) in the junction box, a illuminated bi-directional switch can be used as an illuminated switch.
Normally the lighting element is connected in parallel with the switch contacts. To eliminate the charge of the energy-saving lamp capacitor, it is necessary to connect the backlight element in a non-standard way. This is only possible if the switch illumination element is connected with flexible conductors.
One wire of the lighting element is connected to one output terminal of the switch, and the other, using a suitable mounting terminal, to the neutral. Place the mounting terminal itself in the installation box, behind the switch mechanism. Now, when the lighting is off, power is supplied only to the backlight element. When the light is turned on, the backlight goes out and power is supplied to the lamp.
Installing Light Switches
Light switches should be installed in a relatively accessible location – usually somewhere near a door at about shoulder or waist height. Electrical regulations prohibit installation of devices within reach of a sink, bathtub, or shower. The methods for laying the cable and fastening the mounting boxes are similar to those used when installing sockets.
- Basic lighting controls
The illustration shows the rear side of the switch with spring terminals. Connect the green-yellow core to the ground terminal of the lamp (chandelier). If there is no such terminal, then simply insulate the end of the wire in the lamp.
- Replacing switches
Replacing a defective product basically consists of connecting the existing wires to a new switch. In this case, it is necessary to ensure that everything is done in exactly the same way as in the old device.
Switches with illumination are connected to incandescent lamps in the same way as models without it. When mounting or connecting wires to the device, it may be necessary to remove the key. To do this, carefully pry it with a screwdriver from the side. Many switches have special slots that make this operation easier.
Check if the new switch is compatible with the old back box. Otherwise, you will have to replace it. If you can use the old box, fasten the product with the old mounting screws. If you want to change the surface switch to a built-in one, remove the old device, attach the mounting box to the location and circle it around the contour. Cut the wall to the depth of the new box and secure it to the masonry.
Be very careful not to damage the existing wiring!
When using incandescent lamps, switches with illumination are connected in the same way as devices without it.
- Power outage
Always turn off the relevant circuit breaker before disassembling the circuit breaker.
Lighting control from multiple locations
There are times when it is convenient to be able to turn the lights on and off from two locations, such as at the start and end of a long hallway or staircase.
- Double-sided lighting
The only difference between installing a luminaire with double-sided control and a conventional luminaire is the circuit for connecting switches (switches).
- Mount the luminaire and both switches in two directions, then run a 1.5 mm2 cable from the power source to the luminaire and from it to the nearest switch.
Do not connect new wiring to the lighting circuit until work is completed.
- Run a 1.5 mm cable between the switches 2 .
- To terminal L of the first switch (left in the diagram), a phase conductor is connected from the source – a junction box or shield, and to terminals 1 and 2 – two conductors connecting it to another switch.
- In the second switch, connect the two wires coming from the first switch to terminals 1 and 2, and connect the L terminal to the live terminal of the luminaire.
- Also connect the yellow-green wire to the ground terminal of the luminaire (if not, then insulate its end), and the blue wire to the neutral terminal.
- Make sure the power is off and connect all new wiring to the panel or mains in the junction box.
Check new wiring!
- Three way lighting
By adding an intermediate switch to the circuit described above, the luminaire can be controlled from three places.
This switch is placed in the gap of the connecting wires between two other switches.
- In one position of the intermediate switch key, terminal L1 closes with terminal 3, terminal L2 with terminal 4.
- In another key position: L1 with terminal 4 and L2 with terminal 3.
The phase terminals L1 and L2 are connected to terminals 1 and 2 of the first two-way switch, and the output terminals are connected to terminals 1 and 2 of the second two-way switch. If necessary, you can increase the number of control points by adding intermediate switches to the circuit.
Three-place lighting control circuit
- Lamp supply circuit open. Pressing the key of any switch will turn on the lamp.
- The key of the intermediate (middle) switch is pressed, the circuit is closed, the lamp is on. The red dashed line shows the flow of electric current. Pressing the key of any switch will turn off the lamp.
3 dimmer connection diagrams – installation from A to Z with and without a pass-through switch, with keys, to the LED strip.
Once you have decided on the brand and type of dimmer to control the lighting, it must somehow be connected.
In addition to simple models, where there are only two input-output terminals, do not forget about other nuances. Therefore, let’s take a step-by-step look at from A to Z the main schemes for connecting a dimmer to a lighting network that you may encounter.
On the one hand, such a controller can be turned on to control one or more lamps as a single electrical point. It doesn’t matter if it’s a touch dimmer or turn-and-push.
And you can use a walk-through dimmer and control the light from different places in your apartment or house.
But in general, before connecting any lamp in the apartment, it would not hurt to find out if it can be dimmed at all. After all, with this case, especially with LED lamps, there are many problems.
When it comes to conventional incandescent or halogen lamps, there is no need to rack your brains.
Simple dimmer wiring diagram
If you need to replace a conventional light switch with a dimmer, then the simplest connection diagram is as follows:
Or in a more expanded form:
Scheme No. 1
In fact, all that is required of you is to pass a phase through it. That is, put in a wiring gap, as well as a simple one-button switch.
An exception may be touch dimmers with a digital display and a front panel display. For example, like Uniel and other models.
These dimmers must be connected to both phase and neutral conductors. They have 4 slots for wire entry. Input phase-zero and output phase-zero.
Such a dimmer will not work without zero. If you have only two wires sticking out of the mounting box on the wall (this pattern is observed in 99% of users), you will also have to pull a “clean” zero.
The same applies to all kinds of universal dimmers that can be used in a wide range and connected with other modules – light sensors, motion sensors, etc.
For low-power luminaires that cannot be normally adjusted, a dimmer with an additional neutral lead can also be used. This is due to the fact that when the sinusoid passes through the zero mark and the lamp power is low, the control element cannot determine when it should close.
Therefore, always think carefully before purchasing newfangled and fancy models. Potentially, the “N” icon on the dimmer housing should scare you away from such a purchase.
Will you be able to connect them without unraveling, chasing the walls and peeling off the wallpaper, the big question is.
This does not apply to other simple specimens. You can install them yourself instead of a simple light switch.
It is enough to pull out the insides of the one-keyboard, and connect the two wires that will stick out of the box to the two terminals of the dimmer.
If you have a two-gang switch that starts each half of the chandelier in turn, then there is nothing complicated.
In this case, there will be three wires in the junction box – one incoming phase and two outgoing to the luminaire. The main thing is to find them correctly and not to confuse them. This will help you detailed instructions set out in a separate article.
Twist these two wires together and connect them to the dimmer’s terminal clamp, marked as “dimmed load” or numbers 1,2. Connect the supply phase to the other terminal.
There is no particular difference in polarity. Even if you mix up the clamps, the lamp will still burn and work.
It is desirable that the dimmer should receive exactly the phase, and not zero. Firstly, it is not clear how the device will behave in this case, especially stuffed with electronics. Secondly, do not forget about the correct connection of the wires to the light bulb holder.
According to safety regulations, the phase must not be present on the threaded part.
Also beware of backlit dimmers.
Separate specimens with an LED in the case, it is “thanks” to this diode that they can, even in the state unscrewed to a click, give a light bulb on an empty cartridge, a voltage above 100V.
You have to put additional resistance or capacitors in order to bypass the voltage and prevent unpleasant flicker.
All of the above applies primarily to replacing a switch with a dimmer in an already equipped apartment. Let’s also look at the step-by-step installation of all electrical wiring associated with this type of work.
What materials might you need for installation? If you do not have ready-made wiring and we are talking about a major overhaul in the apartment, which is called from scratch, then buy:
- two-core cable VVGng-Ls 2*1.5mm2
- three-core cable VVGng-Ls 3*1.5mm2
Why exactly VVGng-Ls, and not any other, can be found here.
- dimmer itself
- dimmable lamp or lamp
- Vago clamps or crimp sleeves
First, pull a 3-core cable from the electrical panel to the distribution box where all ends of the electrics will be switched.
In the panel, connect the cable cores to a separate switch.
In order not to confuse the phase, zero and ground, it is better to sign the conductors with a marker L, N, Pe or remember and navigate by color.
An earth conductor is a must if your chandelier or lamp has a metal body. When the material is plastic, then the Pe core can be omitted, but it is still desirable to lay it.
Maybe in the future you will change the brand of the lamp, or in case of accidental damage to the phase or zero, this very core can be used as a backup. You will save yourself a bunch of wires, money and nerves.
Further from the junction box, lower the cable down to the place where the dimmer is installed. A brand of two-core cable is already used here. Of course, provided that you bought a regular dimmer.
This cable will only carry phase. You can designate one core as L (power), the other Llight (it will go to the lamp).
You have laid two cables, the third one is left, which will go along the ceiling directly to the chandelier. You also lay it from this junction box. The number of veins is three.
Strip the ends of the cable on both sides and sign according to the colors: Llight – phase, N-zero, Pe-ground.
After all these manipulations, it is required to correctly connect the cores of all cables brought into the junction box. For this, it was recommended to sign them.
In order not to confuse anything, first combine the neutral conductors, then the ground ends.
They always go directly to the bulb, bypassing any switches and regulators. After that, the phase that comes from the shield is connected to the residential one going down to the dimmer.
You should have only two wires Llight left, that is, those ends that directly supply the phase from the dimmer to the lamp.
The connection in the junction box is ready and it is closed. It remains to connect the dimmer itself and the chandelier.
The dimmer is dismantled before installation. To do this, first remove the rotary-push “head”, or key.
And then, unscrewing the hidden nut or screws with a screwdriver, the plastic housing is removed.
Phase L is connected to the appropriate connector L. The second terminal, marked as a dimmable load, is connected to the conductor Llight.
This terminal is usually marked with a wavy line icon or a light bulb symbol.
After connecting the ends, fix the housing in the mounting box and install the decorative frame.
At the very end, connect the output wires on the ceiling to a chandelier or other lamp.
This can be done through insulated sleeves or Wago clamps.
Dimming a table lamp
If you need to dim a table lamp or a night lamp instead of a ceiling lamp, then this whole complicated procedure can be avoided.
It is enough to disconnect and throw out the factory power cord and connect a special dimmer on the cord in its place.
In stores and Ali is full of the same models. Individual boxes are also sold without wires.
You’ll need them if you don’t want to throw away the factory cord from your desk lamp.
For those who do not want to get into such a jungle and remake connection schemes, dimmers are sold in a socket.
Plug this design into the nearest socket, and through it you connect the table lamp plug. And everything is perfectly regulated.
Diagram of connecting a dimmer through
This dimmer is used in conjunction with the dimmer switches. The pass-through scheme is widely used in the bedroom.
The switch is placed at the entrance to the room, and the dimmer is mounted near the bed. He went in – turned on the light, went to bed – adjusted the desired brightness or created twilight for watching TV. Before going to bed, without getting out of bed, turned it off.
Pass-through dimmers are usually marked with arrows pointing in different directions.
There can be 4 terminals in total. The “X” terminal, located on the right, is usually not involved in the circuit in any way and can be used as an additional terminal. You don’t need to connect anything to it.
If you come across such a dimmer, but you do not want to use it as a pass-through at all, then the power phase should be inserted into the connector with the arrow pointing inward.
On a normal dimmer switch with two arrows pointing inward, you can select any contact. This will not affect the performance of the device.
For the installation of a dimmer through, the same materials are required, only the cable must be 3-core. The stages of work are practically repeated.
1 Mounting the cable from the electrical panel to the distribution box.
2 Laying a three-core cable from the box to the dimmer installation site.
Ends sign as:
- Llight – phase leaving the lamp
- L1 and L2 – communication with feedthrough switch
3Mounting the cable from the junction box to the installation site of the through switch.
A three-core cable is used, marked – L, L1, L2.
4Installing the cable to the luminaire itself.
As a result, in one junction box you will immediately have 12 cores. It is very easy to get confused in them, so never be lazy to sign the wires.
Start the connection with zero and ground conductors. It is difficult to confuse them.
Next, divide the remaining cores into groups (2 wires each) and connect them together.
In the end, you should get the following circuit or chain:
- phase came to the
- left her for a pass switch + returned back
- went to the pass-through dimmer
- came back and entered the lamp through Llight
In this case, the power supply of the dimmer and the switch are interconnected through the conductors L1 and L2. Due to which, the chandelier will be controlled from two places.
Check the correctness of the assembled circuit and connect the dimmer itself.
Insert the conductors from the L1 and L2 feed-through switch into terminals 1 and 2 (or into terminals with arrows). On the case, look for the icon that unites them.
On the “dimmable load” terminal, connect the phase Llight, which goes to the luminaire.
Fix the dimmer in the mounting box and install the trim frame. It remains to connect the pass-through switch.
Look for a common terminal on it and apply the phase coming from the junction box to it.
Connect the two remaining ends L1 and L2 in any order.
After checking the functionality of the circuit, mount the switch in the wall and do the finishing work.
If suddenly the light does not light up, do not forget that such mechanisms have built-in fuses. Often even two (one spare).
Check them for integrity with a multimeter and replace if necessary.
By the way, instead of the second pass-through switch, no one forbids you to use the second dimmer. The connection scheme of such an assembly:
Pleasure is certainly not cheap, but sometimes it justifies itself.
Connection diagram and control of the dimmer from anywhere
If you want something cheaper, pay attention to dimmers with three contacts. They can also work like walk-throughs, but do not require special switches. For example, separate models from Legrand or Schneider.
Their third contact is used to connect non-fixed buttons, like a bell. Pressed once – they gave the command to turn on the dimmer. They kept it longer – dimming began.
The wiring diagram here is as follows.
Connecting LED strip
Through special dimmers, you can connect not only lighting bulbs, but also LED strip or low-voltage Led lamps.
When connecting remotely powered dimmable LED lamps, keep in mind that the dimmer is placed before the driver, not after it.
But on Led tapes, in the connection diagram, it goes after the power supply for 12-36V.
In addition to indoor models, there are also modular units. They are mounted on a DIN rail in the electrical panel.
Through them you can control the lighting in the entrance, stairwell or on the street.
They come with a remote button or switch in the form of a key.