Light switch sparks when turned on: causes and solutions

The switch may require replacement for a variety of reasons. Sometimes the box just breaks or wears out. It won’t take much time to carry out the whole complex of work yourself. It is known that replacing an old switch with a new one takes no more than 20 minutes even for an untrained person. However, before starting work, you need to take precautions. In this article we will tell you how to replace a light switch in an apartment with your own hands, and consider options for single-key and two-key switches.

Repair technology

So, to make the repair instructions clear to you, we will consider it step by step, with photo examples for each important point of repair.

First you need to prepare a tool: a marker, fine-grained sandpaper, an indicator and a regular screwdriver.
Turn off the circuit breaker at the input panel to de-energize the electrical network in the house and protect yourself from electric shock.
Make sure there is no voltage in the room by checking the presence of power at a nearby outlet yourself using the indicator. If you do not know, we recommend that you read the instructions to which we referred.
Remove the light switch from the gate. Before repairing the product, you need to remove the decorative cover yourself, check again that there is no voltage with an indicator screwdriver, unscrew the side screws and pull the housing out of the socket.
Disconnect the wires. If the light switch is a two-key switch, we recommend marking with a marker which of the wires is the input one, so as not to confuse it later and to make the connection correctly on your own.
Disassemble the case and get to the contacts, which are most likely the cause of the repair. These structural elements are located immediately behind the plastic key, which is secured with screws. Repairing them will not be difficult, as you will see further.
Visually inspect the contacts in the form of a hemisphere (you can see them in the photo) and if they are burnt, use fine-grained sandpaper to clean them to a metallic shine. If you cannot remove the carbon deposits well with sandpaper, you can carefully clean it with the tip of a screwdriver. This is enough to fix the light switch yourself.
Reassemble the housing in reverse order. The video below shows how a light switch is disassembled and assembled at home.
Connect the wires and install the housing in the socket box.
Turn on the machine on the dashboard and check if the light switch works. If the switch does not crack and works correctly, you can be proud - you managed to fix the product. If the light is on when the switch is off, it means that you did not clean the contacts properly or did not connect correctly, so you will have to do everything again.

Video instructions for assembling the case

Thus, in 10 steps you can repair the product yourself. As you can see, the repair is not difficult and even a novice electrician can do it. We also recommend that you familiarize yourself with the tips provided below, which will allow you to quickly and correctly repair a switch in your apartment.

If an old-style switch breaks, you can of course fix it, but there is no point in doing so, because... Every part wears out over time, and in electrical work it is very dangerous to use old switches and sockets, especially if they often break down. Today, even such leading companies as Legrand have inexpensive but reliable products, even with lighting, a chain (cord) or a dimmer.
The reason why the contacts on the key switch burn out quickly is because the light bulbs are too powerful. We recommend replacing incandescent lamps with more efficient and at the same time less powerful light sources -. In this case, you can forget about repairing the switch for a long time.
Before proceeding with complete disassembly of the case, check how well the wires are tightened with screws. You may be able to fix the switch simply by tightening the screws with a screwdriver.
In order not to confuse the order of assembly of spare parts of a disassembled case, we recommend using a camera: take photographs of each of the disassembly stages one by one and, if necessary, assemble the structure from the photo.

One of the main malfunctions of switching devices is sparking contacts or their complete absence. The main cause of this problem is wear of the contact system or failure of other components of the device. If you do nothing about it, you will end up having to completely replace the switch, relay, or other switching device. In addition, sparks and heat can cause a fire. But let's take a closer look at the reasons for sparking contacts and how to eliminate them.

Features of disassembling the device and cleaning contacts

If the dimmer switch for the light line shorts when turned on, you need to disassemble and clean the contacts. The work is carried out as follows:

Removing the adjustment knob. You will need to remove semicircular parts or slots. Hold the body with one hand, and gently pull the handle with the other.
Removing the mounting locknut or screws. Use a screwdriver by turning it counterclockwise.
Removing the plastic cover and frame.
Loose internal fasteners of the dimmer mechanism.
Removing the switch from the socket box.

The contacts have the shape of hemispheres. If carbon deposits are detected, the elements should be cleaned to a shine with sandpaper. If the carbon deposits are not completely removed, the contacts are cleaned with the tip of a screwdriver.

Before completely assembling the case, it is better to check whether the wires are tightly tightened.

Why do energy-saving lamps that are turned off blink?

The blinking of electric lamps is clearly visible at night or in a dark room. These are noticeable flashes of light with a frequency of approximately once per second. Here the problem may also be hidden in the backlit switch. The problem does not exist on switches that do not have such backlighting.

The reason is this. Every energy saving lamp has a capacitor that runs the lamp. When the switch is turned off, its LED backlight is on. This means that a small electric current passes through it (from the mains and through our energy-saving lamp).

It is this small flowing current that charges the capacitor, which at a certain point in time starts the energy-saving lamp. Then a small flash occurs and the capacitor discharges again and the process repeats. This is why energy-saving light bulbs flicker.

How to repair touch switches

Touch switch board
Touch modifications are equipped with a remote control and special boards with control chips. It is worth disassembling such a switch after reading the manufacturer's instructions.

Device repair:

Removing the decorative trim.
Visual search for the panel with sensors, which is located under the plate. Depending on the number of lines served, there are 1-3 elements.
Search for a sensitive area on the pad - sensors are indicated by circles.
Detection of LEDs indicating the position of the switch (red - on, blue - off). Under this panel there are nodes to which conductors are connected.
Disconnecting inputs and outputs. You need to remove the clips that secure the touchpad.
Removing the bolts from the housing mounted on the socket box and inspecting problem areas.
Checking voltage on individual cables. The faulty wire is replaced.
Reassembling the mechanism. The main unit is connected to the power supply, placed in the socket and secured with screws. After this, the touch panel and decorative overlay are attached.

Connection diagram for PV cables in the distribution box

Schemes for installing a changeover switch
An important step is assembling the circuit of the pass-through switch in the distribution box. 4 wires with 3 cores go to it - a power cable from the automatic light control from the switchboard, a cable to the 1st and 2nd switch, a cable to the light source.

During the work you need to focus on the color of the wire:

phase – white/gray;
zero – blue/brown;
earth – yellow-green/black.

The assembly provides the following step-by-step algorithm:

Connection of the neutral core coming from the input cable of the machine and the neutral wire going to the lamp with terminals.
Connecting all earth conductors in the presence of a grounding conductor. The ground from the input is thrown onto the outlet ground using terminals.
Ground connection to the housing of the lighting device.
Coupling the phase from the input cable with the phase from the outgoing cable and fastening them to a common terminal in the 1st switch.
Connection of the common wire of the 2nd switch with the phase of the lighting cable terminal.
Connection of secondary outgoing conductors of switches No. 1 and No. 2.
Applying voltage and testing the design.

What to do if there is a wiring smell in the apartment

It is difficult to notice a wiring fault if there are no obvious signs, and they appear late.

Therefore, in fire reports there are many cases with the most common problem being a short circuit. What to do if the smell of burnt wiring appears in the apartment?

#2

Posted May 28, 2008 - 12:59

Well, what can I tell you, climb into the panel and look for short ones and twists. If the stop lights are constantly on, it means the limit switch is jammed under the pedal or the wiring from it. If the backlight of the buttons does not light up, the brightness control has probably failed. It's easy to check, remove the connector from it and short-circuit it. You can only get rid of the rest by picking the wires.

General progress of repair work

Checking for no voltage

Important! There is no need to make special efforts to disassemble the case, since usually the cover of a closed switch can be easily removed

Removing the switch housing

Removing the switch cover

If a switch with two buttons is closed, then mark with a felt-tip pen the wire that supplies electricity and is common to both switching modes.

Switch screw location

Removing the mounting screws

Almost every apartment owner is faced with such a problem as a faulty light switch. If such a situation arises, you do not need to immediately call a specialist to your home. Most often, you can fix this problem yourself. A light switch malfunction is most often caused by poor contact between the connecting plates of the electrical wires. To fix it, you just need to clean the contacts and check the tightness of the wires in the switch connectors.

The whole process consists of three stages: preparatory work; disassembling and cleaning contacts; assembling and installing the light switch in its original place.

Preparatory process

At the initial stage of repairing the switch, you need to completely de-energize this section of the electrical network and prepare the necessary devices and tools. To clean the disassembly and strip the contacts, you will need a screwdriver, an electricity indicator and regular sandpaper or a file.

It is important that there is no electricity in the network. This is why you need an indicator. A file is useful for removing plaque from the contacts, and a screwdriver for unscrewing and assembling the entire installation

A file is useful for removing plaque from the contacts, and a screwdriver for unscrewing and assembling the entire installation.

Disassembling the switch and cleaning the contacts

First you need to make sure that there is actually no electricity going to the light switch. Then, prying the device button with a screwdriver, remove it from the device. The plastic shell can also be removed with a little force.

The next step is to remove the switch from its mounting location. To remove it from the plastic shell in the wall, you need to loosen two screws. After unscrewing them a little, we pull the device out of the wall. To disconnect the light switch from the wires, loosen the fasteners and pull them out of the clamps.

Having seen blackened and coated contacts, we clean them with a file or special sandpaper. The cleaning process must be continued until plaque and fumes are completely removed.

Assembly and installation of the switch

After completing all the steps to clean the contacts from plaque, you can begin assembling the device. To do this, you need to connect all the wires to their original place and tighten the clamps

It is important to create excellent communication to prevent bad interactions. Having assembled the entire structure, we insert the switch into the plastic case. After making it level and even, tighten both fastening screws

If the plastic frame is not put in its original place, you will have to loosen the screws and put it on until the switch is completely installed in the network. Although, if the switch is properly mounted in the wall, this should not be a problem.

After making it level and even, tighten both fastening screws. If the plastic frame is not put in its original place, you will have to loosen the screws and put it on until the switch is completely installed in the network. Although, if the switch is properly mounted in the wall, this should not be a problem.

At the final stage, insert the power button and start the central electricity monitoring device. Now we check the functionality of the switch. To do this, turn on the light in the room several times. If everything works stably, then calling an electrician will not be necessary.

If the switch has stopped working, then you should look into the root cause of its failure. Today there can be many reasons. You don't necessarily need to call a professional. You can repair the light switch yourself. The causes of failure are usually minor and therefore almost anyone can cope with them.

Sometimes, in order to restore the device's operation, you will need to clean the switch contacts. In this article we have provided detailed information on how to fix a light switch. The reasons for breakage of the switch can be varied, and in this article we will look at them.

Step-by-step instruction

Let's look at how to change the switch.

Preparatory stage

The main thing when working with electricity is safety. If you lack confidence in your own abilities, it is recommended to use the services of a professional electrician.

If you decide to do the work yourself, follow these preparatory steps:

The lack of light is not caused by problems in the electrical network, but by a burnt-out cartridge. Checking the cartridge.
Let's see if there is light in other parts of the house (apartment).
If, based on the results of the check, there are no malfunctions not related to the electrical network, we proceed to dismantling the switch. Before changing the switch, we turn off the power to the apartment. To do this we use a switch. We check the mains voltage with an indicator. We inform family members about the renovation work. No one should use the light while the switch is being replaced.

Causes of sparks and arcs

Before we look at why contacts spark, let's understand the basic concepts. The switching device and its contact system must provide a reliable connection with the possibility of breaking it at any time. The contacts consist of two electrical plates, which in the closed position must be securely pressed against each other.

An arc occurs when switching inductive circuits. These include various electric motors and solenoids, but it is worth remembering that even a straight piece of wire has a certain inductance, and the longer it is, the greater it is. At the same time, the current in the inductance cannot stop instantly - this is described in the laws of commutation. Therefore, a self-inductive emf is formed at the terminals of the inductive load, its value is described by the formula:

E=L*dI/dt

Interesting! In our case, the rate of change of current plays an important role. When turned off, it is extremely high, and accordingly the EMF will tend to large values, up to tens of kilovolts (for example, a car ignition system).

As a result, the EMF increases to such an extent that its value breaks the gap between the contacts - or sparks are formed. The quality of any connections is described by their contact resistance: the lower, the better the connection and the less heating. When they open, it increases sharply and tends to infinity. At the same moment, the area of their contact heats up.

In addition, between the open contacts against the background of increasing self-induction EMF and increased air temperature due to heating of the surfaces when the plates are opened, air ionization occurs. As a result, all the conditions for arcing and sparking are present.

If we talk about why contacts spark when an electrical circuit is closed, then this happens not with an inductive load, but with a capacitive load. You see this every time you plug in your laptop or phone charger. The fact is that the discharged capacitance (capacitor) at the input of the device at the initial moment of time represents a short-circuited section of the circuit, the current of which decreases as it is charged.

If you observe sparking in a relay or switch in the closed position, the reason for this is the poor condition of the contact surfaces and their high temperature.

Signs of malfunction and main types of breakdowns

The switch is faulty if you hear a crackling noise when you turn it on.

Before you can fix a faulty switch, you first need to understand how it works and also become familiar with the main reasons why it could break. Characteristic signs of failure:

when you press the key, the changeover mechanism begins to jam and does not move to the desired position;
at the moment of switching, you can hear a crackling sound, and sometimes you can notice something sparkling inside;
After pressing the button, the device simply does not turn on the lighting.

Typically, these malfunctions are observed with only one of the keys, but the possibility of failure of two or even 3 switching mechanisms at once cannot be ruled out.

In the first case, the axis on which the base of the key is fixed could presumably fall out or a foreign object could get inside (dust accumulated). With characteristic crackling and sparking, one of the closed contacts or both of them has probably burnt out. If the light does not turn on at all after pressing the key, the problem is most likely that the contact at one of the points where the conductors connect to the terminals is broken and the current is not supplied to the load. In this case, it is first checked to see if the voltage has gone out in the entire apartment and that the light bulb is fully operational.

Practical recommendations

These tips will help you extend the life of the switch, and if it breaks, avoid unnecessary work:

If a device that is broken was installed a long time ago, and even more so if it is an old model, it is not worth repairing. Firstly, it will not be easy due to the natural wear and tear of its elements, and secondly, it is undesirable to use old electrical appliances for fire safety reasons.
Often the switch contacts burn out due to the use of too powerful light bulbs. We advise you to replace them with products of lower power, and best of all, with modern LED ones. The brightness of their glow is no less than that of conventional incandescent lamps, and the power consumption is much lower.
Take your time to remove and disassemble the switch housing. Sometimes the cause of the malfunction is loose wires, and tightening the screws is enough to return the device to functionality.

Visually replace and repair the switch on video

This concludes our story. We think that this information is quite enough to understand how to fix a light switch without the help of an electrician. Using this material, you can repair the switch yourself in a short time, not only saving money, but also increasing your authority in the eyes of loved ones.

Repair procedure

If the switch sparks due to a loose contact, it is necessary to ensure a continuous connection between the pair and the receiving plate when the light is on.

When a light switch crackles, there is probably a short circuit in the circuit, so you need to clean the wire contacts and reconnect the device to the line. If it continues to work incorrectly, you need to replace the device with a new one. A shorted switch cannot be used.

How to repair your device:

Disconnect the power supply and check with an indicator screwdriver that there is no voltage.
If the key switch sparks, you need to pry off the housing with a screwdriver.
Pull out the circuit of the switch cover, check the voltage at the terminals.
If there is carbon deposits on the wires, they need to be disconnected from the socket and cleaned.
When the indicator sparks due to unstable contact, it is enough to tighten the terminals with screws.

After this, you need to assemble the device in the same sequence

It is necessary to pay attention that a phase should be connected to the contacts of the key switch - this guarantees the safety of replacing lamps in lighting fixtures. By pressing the key the phase is switched off

The current and operating voltage are indicated on the inside of the case.
An important parameter is the build quality, on which the operation of the device depends.
The optimal height for installing the switch from the floor is one meter.
Installation of devices is carried out on phase wires in socket boxes.
First you need to connect the wires, then install the mechanism in the box.
The screws are tightened alternately to avoid distortion of the device.

After snapping the frame, the switch should not wobble. The functionality of the device is checked after turning on the network. If the device sparks when the light is turned on, there is no stable contact between the wire and the plate. The device will heat up, causing the plastic case to melt. Any breakdown of electrical devices must be corrected in a timely manner.

Assembly

After repairing the device and preliminary checking its functionality by restoring the current supply, you should install it in its place and assemble its parts in the reverse order. There shouldn't be any particular difficulties in this matter. However, if you still have doubts, you can use the photographic material that you prepared for yourself in advance (even at the disassembly stage). Having started assembling the switch, you first need to connect the wire that we previously highlighted with a marker to one of the terminals, and after that all the remaining wires. At the next stage, the device is fixed in the socket box and the housing rim, decorative cover and light on/off buttons are installed.

At this point, the process of repairing a switch at home can be considered complete.

By following safety precautions and the above tips, acting step by step and with due care, you can extend the life of the switches in your home without much effort and without the help of strangers.

List of required tools

Some consumers, if they detect a malfunction of the switch due to sparking, crackling or humming of the device, immediately turn to electricians. However, damage that can be repaired can be repaired yourself. In most cases, it is enough to bend the contacts for the device to function normally.

The following tools are needed for repairs:

indicator screwdriver with a lamp or electronic display;
a regular type screwdriver for unscrewing screws/screws;
insulating tape and fine-grain sandpaper;
pliers, marker, knife for stripping wiring insulation.

All switches have a plastic housing, a protective frame and an internal operating mechanism. The frame can be attached to the mechanism with latches or screws. The socket box contains a working mechanism, fixed with spacer tabs or screws. To perform repairs, you need to provide access to the contact group by removing the outer box from the device.

We are preparing

Before connecting the switch, it is necessary to prepare it for installation. We will discuss how to do this below.

Remove the key by prying it in the center on the left or right side with a flat-head screwdriver.

Unscrew the two screws located diagonally.

Now the mechanism is available to us. The mechanisms of single-key switches can be of different designs, but they have the same connection principle. There must be two contact clamps and spacer tabs for attaching to the socket box.

In our mechanism, the screws of the spacer legs are located on the left and right.

They set the metal fixation claws in motion.

And two contact screw clamps for connecting wire cores.

By unscrewing or tightening the contact screw, we move the pressure plate, designed to securely fix the core in the contact.

Each contact provides connections from 1 to 2 wires.

Tips for selection and installation

You need to choose electrical devices responsibly so that incorrect operation of the devices does not lead to a fire in the wiring. Minor problems lead to home discomfort - the lights flicker, the room lighting is dim.

Useful recommendations on how to choose a device and install the device so that the switch does not spark:

The current and operating voltage are indicated on the inside of the case.
An important parameter is the build quality, on which the operation of the device depends.
The optimal height for installing the switch from the floor is one meter.
Installation of devices is carried out on phase wires in socket boxes.
First you need to connect the wires, then install the mechanism in the box.
The screws are tightened alternately to avoid distortion of the device.

Why are Chinese machines so unreliable?

Everyone understands that the only advantage of the “Chinese” is low cost. But it is achieved precisely by saving on materials. Budget Chinese models have cheap everything: plastic, metal, release mechanisms.

All these reductions in price will sooner or later come out sideways. For example, even due to elementary savings on rivets, the strength of the entire structure is lost. As a result, some parts fall off over time and the cocking mechanism weakens. This causes the problems listed above and will require replacement soon.

Electricians often swear at the “Chinese”. In fact, if you take the cheapest ones and take them apart to see what's inside, you'll be surprised how they even work. They usually have a lightweight design, thin springs, power contacts that barely hold, and other obvious problems. This doesn't inspire confidence.

Even worse are Chinese counterfeits of well-known brands, sold below the cost of the originals. Unfortunately, there are a lot of them on the CIS market. It is quite natural that the most popular brand, ABB, has the most counterfeits. This is a Swedish-Swiss manufacturer that produces fairly high-quality machines. Accordingly, you yourself must understand that they will not be too cheap.

To achieve high reliability and quality of releases, more expensive metals are needed: sputtering of silver, gold, etc. In addition, Europeans usually do not skimp on materials. There will definitely be an arc chute there and a heat sink will be made. And this all increases the cost, so there are no good machines cheaper than $3.

Why is the switch rattling?

The switch may crackle and even spark with a bang for the following reasons:

Poor contact, the screw clamps are loose, you need to turn off the electricity in the panel, remove the switch keys and tighten the screw clamps of the wires, it is important not to confuse them with the screws securing the switch, these are the screws in the photo. Perhaps your chandelier or lamps have too powerful lamps, the switch is not designed for such a load (I mean the total load from all the lamps), it gets hot, sparks and crackles

Perhaps your chandelier or lamps have too powerful lamps, the switch is not designed for such a load (I mean the total load from all the lamps), it gets hot, sparks and crackles.

The lamps in the lighting fixtures must be changed to less powerful ones.

High humidity in the premises leads to oxidation of the contacts; the contacts must be cleaned and tightened (again, first turn off the electricity in the panel).

The wear and tear of the switch (its operating mechanism) can only be helped by replacing the switch with a new one; switches have their own service life, apparently it is completely exhausted.

Constant voltage drops in the network can lead to crackling and sparking of the switch.

Installing a voltage stabilizer will help.

The spring (more precisely, the plate) that presses the contact when the switch is turned on has weakened; it can also crack, the contacts are not fully closed, in this case either the spring or the switch changes completely.

Several times I encountered factory defects in the switch; they bought inexpensive and therefore low-quality switches.

Started cracking immediately after installation.

In this case, it is better to simply replace the switch with a new, better one.

Very often we are faced with such a problem as the sudden appearance of an abnormal operating sound from a circuit breaker in the panel room.

A slight hum from an electromagnetic starter surprises few people, and some even consider this effect to be its usual mode of operation, although this is not the case for new devices. So what should you do when your machine buzzes like this or buzzes?

Is it worth changing it right away, or is the reason not in it at all, but in the electrical wiring or connected load? Let's take a closer look.

If this sound appears, then first of all decide what it sounds like:

All your further actions will largely depend on this.

Such sounds appear when the machine is energized and under load. That is, current flows through it. Moreover, the greater the load, the louder the machine can make noise.

Circuit breaker hums

Let's look at the first fault, namely humming. If your machine makes a sound during operation like a starter or contactor, this indicates a defect or defect.

Practical recommendations

These tips will help you extend the life of the switch, and if it breaks, avoid unnecessary work:

If a device that is broken was installed a long time ago, and even more so if it is an old model, it is not worth repairing. Firstly, it will not be easy due to the natural wear and tear of its elements, and secondly, it is undesirable to use old electrical appliances for fire safety reasons.
Often the switch contacts burn out due to the use of too powerful light bulbs. We advise you to replace them with products of lower power, and best of all, with modern LED ones. The brightness of their glow is no less than that of conventional incandescent lamps, and the power consumption is much lower.
Take your time to remove and disassemble the switch housing. Sometimes the cause of the malfunction is loose wires, and tightening the screws is enough to return the device to functionality.

Visually replace and repair the switch on video

https://youtube.com/watch?v=%2520%E2%80%B3%26gt%3B

How to prevent sparks

To prevent sparks from forming at the contacts, manufacturers install arc suppression chambers that cool the arc. Some brands may make solderings from materials that are not susceptible to oxidation. Current will pass through them. You can use several methods yourself.

Spark arresting circuits

Suitable for high-speed devices that generate sparks at the moment of closing. Most often there are two options:

For relays and DC starters. You will need a diode with an anode on the negative pole and a cathode on the positive pole. Energy dissipation occurs on the active part (self-induction). The diode will close the circuit.
Snubber. The shunt RC circuit is designed to dissipate the energy accumulated in the inductance at the moment of active resistance of the network.

The contacts are located close together, so the spark extinguishing circuit reduces the load.

Pressure plates

The method is suitable for sparking contacts of a starter or machine. A special spring mechanism ensures tight contact between the contact pads. To connect, you will need to install a spring mechanism in the closed contact position, retracting it and lowering it back. A click/thump should be heard.

Removing carbon deposits

You can clean the surface of conductors not only with fine sandpaper. An eraser or a wooden match will ensure a smooth surface and eliminate the risk of increasing contact resistance.