Defective circuit breaker. Knocks out the machine, the reasons

Modern circuit breakers are not intended for repair because they are supplied in a non-separable housing. The manufacturer assumes their replacement, at the same time, domestic-made automatic machines of the AP type assumed not only disassembly, but adjustment, with a certain skill you could assemble one completely working out of several faulty ones. From the article you will learn what are the malfunctions of circuit breakers and how to fix them. The machines under consideration are used in electrical circuits with voltages up to 1000 V, to protect risers and supply lines.

How the protection apparatus works

To understand the causes of all malfunctions, you need to consider the device of the machine. It consists of a pair of power contacts, a thermal disconnector and an electromagnetic disconnector.

The thermal disconnector trips slowly, with a slight (up to 2 or more times, depending on the time-current characteristics of a particular circuit breaker), exceeding the rated current. Electromagnetic - in the event of a short circuit or exceeding the current several times, it is triggered in a fraction of a second. At first glance, it may seem that there is nothing to break here, but let's consider each of the mentioned malfunctions separately.

The main problems with machines

The machine has only three main faults:

Knocks out.
Doesn't turn off.
Not cocked.

Solution: Diagnostics and repair consists in disconnecting the main line cable and replacing it with a temporary one, if it helped, then you have to revise and repair the wiring.

Instantaneous shutdown of the machine is associated with the operation of electromagnetic protection. It does not lock in the on position due to internal problems with the same electromagnetic shielding. You can check the serviceability of the machine by replacing it with a knowingly serviceable one, with the same rated current and sensitivity - if everything worked properly, the reason is in it. If the circuit breaker does not charge without voltage, and there is no short circuit, it needs to be replaced.

Circuit breaker does not turn on

If you lift the lever up, but the circuit breaker does not turn on, and the lever instantly falls down, this is due to either mechanical wear of the machine's components or the presence of a short circuit. You can check this by ringing the supply phase to zero with a low-resistance continuity, for example, a control lamp, or an ohmmeter. High-resistance continuity (for example, LED control) can mislead you and the circuit can ring through the load (light bulbs, heating elements or electric motors). If the circuit is closed, then there is a breakdown of the cable insulation.

Solution: Eliminate the malfunction by replacing the cable or restoring the insulation. If there is no short circuit, then the machine is replaced.

Lever is stuck

Another thing is when you cannot move the machine lever from the lower position, which means that the contact drive mechanism is jammed. This malfunction can occur when disconnected under load, if a strong arc has arisen and its splashes have jammed the moving contact, or rather its assemblies, or it is soldered into the case.

Solution: Grab the lever closer to the base and pull it up strongly, but smoothly, and there is a chance of breaking it off. In the future, you will not be able to use such a machine. It is still likely to jam in the future, then the machine should be replaced. The success rate in this procedure is 50%, in practice the lever often breaks off, especially if it happens in the cold.

The machine does not turn off when there is a short circuit

There can be two reasons for the lack of response to short circuit. First, the contacts are stuck. Due to heating and arcing during openings, the contacts adhered to each other. The second - the mechanism of the electromagnetic disconnector is jammed.

Solution: If the machine does not work in case of short circuits, try to break the contacts with effort, if it does not work, then replace the machine.

How to extend the life of a circuit breaker

Remember two tips:

Do not overload the protected line with a current higher than the rated one.
Do not switch off the machine under load.

While everything is clear with the first tip, the second is a little more complicated. When current flows through the contacts and you are about to disconnect them, an arc occurs. This is due to the truth of the laws of commutation: "The current in the inductor cannot stop instantly."

We got acquainted with the defect caused by what. The circuit breakers will last quite a long time if they are operated within the rated conditions. Modern machines cannot be repaired, so we do not recommend disassembling them, it is better to replace them with a high-quality analogue, for example, Moeller or ABB. For household appliances and active loads, use machines with the letter B, to connect a load with significant starting currents (motor), devices with the letter D are better suited, and the number after the letter indicates the value of the permissible current. Do not connect oxidized wires and always tighten the terminals. Adhering to these tips, malfunctions of circuit breakers will occur much less often, and you will not have to worry about the safety of operating the wiring in an apartment or house.

Surely most of our readers are familiar with the situation when the electricity goes off at home, while the neighbors have everything in order. First of all, you need to check the circuit breakers installed in the switchboard. Most often, it is their disconnection that causes the home network to de-energize. In this article we will talk about why a machine gun knocks out in an apartment or house. The reasons for this phenomenon can be different, and it is important to know them in order to prevent unpleasant consequences associated with the failure of electrical appliances or a fire in the wiring.

Features of the circuit breaker

To understand the reasons for the operation of the circuit breaker, you must first answer the question of what this device is for and what functions it performs. The features of the AV work are as follows:

The main task of the device is to protect electrical wiring and household appliances connected to it from too powerful current arising for various reasons.
The device is mounted on a phase circuit, the rupture of which occurs when the bag is turned off. If the machine has two or more poles, then when it is triggered, the zero circuit will also open.

AB can de-energize the network both during manual shutdown and in the event of an emergency that can lead to damage to the circuit elements.

Knocks out a machine gun: what are the reasons?

Now we directly turn to the question of why the machine knocks out in the dashboard. The automatic machine can be triggered for the following reasons:

Overload in the power grid.
Failure of one of the devices included in the circuit.
Breakage of the lighting fixture.
Defective protective device.

Any of the listed reasons can lead to the fact that AB will knock out. Let's consider each of them in more detail.

Overload

This is the name of the situation when the value of the current in the circuit exceeds the rated current for which the protective switch is designed. For a better understanding, let's give an example.

To work with outlet groups, AB are mainly used, the rated current of which is 16 - 25 A. This indicator corresponds to a total power of 3.5 - 5.5 kW. Suppose that an electric stove with a power of 3 kW, an electric kettle for 1.3 kW, and a microwave oven for 2 kW are connected to the outlet group, for protection of which an automatic switch designed for 25 A is installed.

If we add up the power of the listed household appliances, then we get a load value of 6.3 kW. Considering that the maximum load withstood by the protective device is 5.5 kW, the simultaneous activation of all three devices will lead to the machine knocking out.

To avoid this, do not take lightly the calculation of the total load in the circuit. If connecting the device to a socket group will result in an excess of the total power, it should be connected to a different circuit.

An example of an incorrect calculation of the posting on the video:

Do not try to solve the problem by installing a machine with a higher power rating. If its rating exceeds the one that the electrical wiring can withstand in its cross section, problems are inevitable. In this case, under the influence of too much current, the cable will heat up until the insulating layer melts and causes a short circuit, and in the worst case, a fire. At the same time, the machine will continue to supply current to the circuit until a short circuit occurs. Therefore, if a cable with a cross section of 2.5 mm² is used when laying the line, the AB rating for its protection should not exceed 16 A (for an aluminum conductor) or 25 A (for a copper conductor).

Breakdown of a household appliance

If you plug in a faulty home electrical appliance, then the likelihood that the machine will "shut down" is also quite high. Let's take an example how to find the device that caused the problem.

Let's say an electric stove, microwave and oven are included in the network in the kitchen. A machine gun was knocked out in this chain. To determine the cause of the problem, proceed as follows:

We disconnect all units from the network.
We turn on the machine. If it does not knock it out without load, the wiring and the protective device are in good order.
We connect household equipment one by one. If, for example, when the stove and the microwave oven are turned on, the chain works, and when the oven is turned on, the machine knocks out, the oven is faulty, and it must either be changed or repaired

An example of diagnostics on video:

Some types of household appliances (such as dishwashers or air conditioners) are connected to the mains directly, rather than through an electrical outlet. Such devices must be disconnected from the protective device installed inside the switchboard - this is the only way to check them.

Malfunction of lighting devices

Now let's figure out why the machine knocks out when you turn on any lighting device. In any case, the reason is a malfunction of the latter, which may be as follows:

Short circuit in the lamp base. To find the faulty element, you need to unscrew them all and, screwing in one at a time, turn on the lighting device. When, after screwing in the next light bulb, when the light is turned on, AB is triggered, this means that the cause of the problem has been found. A discovered bulb with a broken base must be replaced with a serviceable one. Of course, if the only light bulb in the device burns out, and the machine gun is knocked out, the cause of the malfunction is obvious, and there is no need to waste time looking for it.

Please note that sometimes the bulbs burn out due to the fault of a faulty switch - this can also be accompanied by the activation of the protective device.

Burning contact between the power cable and the internal wiring of the device. To eliminate the malfunction, it is enough to clean the contact, and then insulate it with high quality.
A short circuit inside the transformer of an LED chandelier. If the inclusion of such a device leads to a knocked-out machine, there is a high probability that this is the problem. For troubleshooting, the non-working transformer will need to be replaced with a serviceable one.

As you can see, the reason for switching off the AB when the lighting device fails is most often a short circuit. At the same time, the wiring does not have time to heat up to a critical level, so the operation is triggered not by a thermal, but by an electromagnetic release.

Failure of the circuit breaker

Malfunctions in the machine itself can also cause a sudden power outage, but this happens very rarely, especially when it comes to models from well-known manufacturers. But if there is a suspicion of a malfunction of the protective device, it should be checked by connecting a new one, obviously working. It is also possible to disconnect the circuit from this AB and connect it to the adjacent bag in the switchboard. If these machines also work, the problem must be looked for elsewhere.

Even a seemingly serviceable machine gun can knock out. Video example:

The reason for the failure of a circuit breaker can also be its long-term operation, during which there is a natural wear of its components and deterioration of their technical parameters. This also applies to releases. As a result, the device may be triggered even if the conductor is slightly hot. This AB must be replaced.

What causes the differential circuit breaker to knock out?

A differential type circuit breaker can de-energize the network for the same reasons as a conventional one (if the wiring is very hot or a short circuit has occurred). But since in its composition, in addition to releases, there is an RCD, it also reacts to the leakage current, therefore, it is not so easy to find the reason for the operation of the difavtomat.

If such a device works for no apparent reason, a more thorough check should be carried out.

Inspect the breaker, if necessary, tighten the contacts. Check the condition of the wiring in the switchboard. If the phase conductor touches the grounded metal case, this can cause knocking out of the differential circuit breaker, although it will not lead to a short circuit.

Let us assume that no faults were found in the switchboard. Consequently, there is a current leak in the protected electrical circuit. Its reasons may be as follows:

Defective electrical appliance. If it breaks through on its body, the RCD of the difavtomat is triggered, the task of which is to prevent people from being shocked.
A short circuit between the protective grounding and zero phase wires, which is sometimes done by inexperienced electricians.

Heavy thunderstorm. Powerful electrical discharges often cause knocking out of the differential protection device. In this case, it is better not to turn on AB until the thunderstorm subsides.
Worn insulating layer of old electrical wiring. In this case, the leakage of electric current occurs through microcracks and triggers the machine. Since such damage is poorly visible to the naked eye, and the defective cable does not heat up, it can be difficult to detect the problem.
A sunken "Test" button on the device or a damaged housing part also triggers the device. In this case, the defective device must be replaced.
Installation of the machine not according to the scheme.

The differential automatic device should be checked from time to time by pressing the "Test" button with the load disconnected. A working device should turn off. If it continues to work, this indicates a violation of the protective function and the need to replace the device.

Why knocks out an RCD - clearly in the video:

Faulty wiring

The reasons for disabling the AV can be:

Worn cable insulation layer.
Poor contact at switch or electrical outlet.

If the problem is in the switch or outlet, then to eliminate the malfunction, you need to open the element, clean the burnt place and connect the cable correctly. With worn insulation, especially when it comes to hidden wiring, it is not easy to find the problem.

In this case, a special device will help - a locator, with which you can detect damage to the cable, even if it is hidden in the wall.

Having determined the place of the malfunction, it must be opened and the malfunction eliminated, and then the groove must be repaired.

Conclusion

In this material, we figured out what reasons, in addition to an excessive heating cable, the circuit breaker can be triggered. Now you know what to do when the light bulb burns out with the simultaneous shutdown of the protective device, as well as how to troubleshoot if the wiring inside the electrical element burns out or if a household appliance breaks down.

The circuit breakers are designed for overload protection. Sometimes, unforeseen situations may arise that lead to the fact that the machine simply "knocks out", it does not "cocked" or "does not turn on".

There can be many reasons for knocking out and disconnecting:

Short circuit;
malfunction of household appliances;
network congestion;
defective machine;
wrong connection.

But you don't need to be an expert to understand what caused the problem.

Machine device

To understand what to do, you need to know a few points about the structure of the machine.

The machine consists of:

Arc-extinguishing chamber (extinguishes the arising electric arc at the contacts);
Pairs of power contacts;
Electromagnetic disconnector (short circuit triggered);
Thermal disconnector. It is triggered when the rated current is exceeded. Each model has its own rated current - 6,10,16,25 (A), etc.). This must be taken into account in order to avoid overload;
Lever, connecting devices, contact diagram.

Determine and eliminate the malfunction on our own

If machine gun "knocked out" when you turn on several household appliances at once - an electric stove, a washing machine, a vacuum cleaner, an electric kettle, a boiler and others - the matter is in the thermal disconnector or in power surge... In this case, the machine turns off to protect the network. You need to know what it is.

Listen - if the machine makes a characteristic noise and crackles - this is a sign of its overload. In this case, it is necessary to turn on household appliances one by one. It does not help - we look at the machine, and if burnt wires are found there, it means that the matter is thermal disconnector, which is out of order from overheating of the power contacts (they cannot be cleaned) or loose wires in the terminal blocks (they can be cleaned and tightened). Manufacturers generally make them non-separable, and only a few provide for the possibility of disassembly and adjustment. Therefore, you have to buy a new AB.

If the integrity of the wiring is broken, a short circuit may occur, as well as with mechanical wear lever AB does not move up... We check the supply phase with a noscale continuity in the form of a control lamp. If the circuit turns out to be closed, it is a cable malfunction, which can be replaced.

Sometimes, the lever can jam and it will not lift up due to load tripping. In this case, you need to pull it up with a smooth but strong movement. It can break off, and then AB replacement is necessary.

In order to exclude option of short circuit, it is necessary to check the wiring. This is a necessary step, which can show the true cause of the trouble - we check the connection of the veins on the terminal blocks at all sockets and switches, and also do not forget about the chandeliers. All loose wires should be tightened and checked for integrity. Within the walls of the short circuit, only a specialist can determine, or in a short section (up to 3 meters) this can be done using a megohmmeter (multimeter). We remove the outlet, disconnect the wires, and connect with one wire to the phase, and the other to zero. If the value is zero, everything is in order, if there are numbers, the contacts are in contact with each other.

Sometimes you can hear a crackling sound and smell a burning smell - there should be no doubt about it. This problem is often solved radically, by changing the electrical wiring with the replacement of all burnt outlets.

If the machine stops working on a short circuit, then the matter is in the contacts that could stick due to heating. You need to either change the machine, or try to break them.

Sometimes the machine can only work for the operation of some kind of household appliance. For example, when a water heater or a washing machine is running, it starts to "knock out". We use the elimination method. After that, we inspect the outlet, and if there are melted contacts there, it means that the short circuit occurred inside the equipment. Next, we check the wiring with a multimeter, and if everything is in order there, then the reason is faulty equipment. More precisely, there may be a short circuit in the supply cord, heating element to the case, and the windings of the electric motor.

There is also the option of breaking the heating element, or a problem in the surge protector. To exclude most options, you should disconnect the supply wires from the heating element and insulate them. After turning on the machine, and if it works, but the machine does not turn off, then the problem is in the heating element, and you can safely change it.

If the dashboard has an input and group machines, and the machine knocks out just at the input, then it is necessary to check the assembly of the dashboard. Depending on which machine turns off, you can understand the direction of the problem - for example, a group of lighting and sockets.

How to avoid breakage of the machine

Network congestion Is the most common problem. Observe the rated current and the connected equipment, and, if necessary, replace the 16 (A) automatic machine with 25 (A).
Do not turn off the machine under load... It is in this case that charring and burning of the wires occurs.
Buy quality models. Manufacturers such as ABB, Legrand, Schneider Electric,Hager, Schrack Technick,Eaton, General Electric, ETI.
Always remember that the quality of the wiring depends largely on the quality of the installation.

Periodically, a situation may arise when the electrical panel is triggered circuit breaker and the room remains without electricity. You do not need to be afraid, because it means that your installed network overload protection system is working correctly! If the machine had not worked, a fire could have occurred, which would have led to tragic consequences.

Usually, tripping occurs due to voltage surges in the network and it is enough to simply put the disconnected circuit breaker or residual current device (RCD) back into the "On" position. But what if the RCD immediately or after a couple of minutes triggers again? This alarm indicates that there are some problems in the electrical wiring network and action needs to be taken to eliminate them.

There are two possible reasons for this situation. Accordingly, the order of your actions when the machine is triggered will also differ. But remember that an independent search and elimination of problems with electrical wiring is possible only with a sufficient level of relevant knowledge and skills and strict adherence to safety rules.

Causes

Short circuit- direct electrical connection of the phase conductors to each other (or phase conductors with zero) and the occurrence, as a result, of a very high current value in the circuit. It occurs when an electrical appliance breaks down or in the event of a malfunction of the electrical wiring itself. The signal of this trouble will be the instantaneous re-shutdown of the machine after it has been moved to the "On" position.

Overload- this is an increase in the total load of all power consumers of the network in terms of power in excess of the permissible norms. For example, if your electrical network allows the sum of the power load of 10 kW, then any excess of this value will cause an overload. The reason for this is the appearance on one phase or several at once of an increased current, leading to the operation of the machine and the break of the circuit. Also, overload occurs when the so-called "imbalance" of the phases. This phenomenon is typical for a three-phase circuit due to the uneven distribution of the load over the phases. The signal of such a malfunction will be the repeated shutdown of the machine after a certain time (up to several minutes) after turning on.

What to do?

First of all, determine which of the machines has worked in the electrical panel. If this is only a general machine, then a short circuit has occurred directly in the electrical panel. On closer inspection, it will be noticeable, in addition, you will smell burnt plastic. If you have the skills, you can start repairing the damage, otherwise you need to call a specialist.

When any linear machine is triggered (line of sockets or lighting), you need to look for a malfunction specifically on the disconnected line.

Line of sockets. We take out all the plugs of electrical appliances from the sockets and try to turn on the machine. If the machine does not turn off, then the problem is the breakdown of one of the devices - electricity consumers. It is not difficult to find it - connect the devices to the sockets one by one and the circuit breaker will "knock out" when the faulty device is connected. If it "knocks out" with all the electrical receivers turned off - the matter is in the damage to the electrical wiring. Then you need to look for a malfunction in sockets and junction boxes - to tighten up the internal contacts first. If this does not lead to anything, then we disconnect the wires in the boxes and "ring" them with a multimeter for the fact of a short circuit. So you can understand which wire or cable needs to be replaced.

Lighting line. A similar principle of action in this case is to de-energize all means of lighting on the line. If the machine turns on, then there is a malfunction in one of the lamps. We turn on each of the lamps one by one, thus finding the faulty one. Found - we examine the contacts in the electric cartridge and proceed to its repair. If the machine did not turn on even with the lamps turned off, then the electrical wiring must be repaired (the problem must be looked for in the same way as in the case of the line of sockets).

And the last thing: try to responsibly treat the choice of circuit breakers in order to avoid major problems in the future.

Electrics are good as long as they work properly. Any electrical malfunction baffles most people on the planet. In this article, we will see how to determine the malfunction of a circuit breaker and how to fix it.

By the way, everything does not always work as it should, not only in electrics. Repair of equipment that helps us, the same workflow, millet, you need to be ready for it. This also applies to road construction equipment. A reliable supplier of spare parts with a wide range of spare parts for most of the world's manufacturers will help in the repair of road construction equipment. Where can I find it? Try it at arsenal-zapchast.ru. You will not regret, there are spare parts for 13 brands of leading manufacturers of road construction equipment.

Circuit breaker and short circuit

I'll start over. The circuit breaker or is designed for (cables and wires of electrical wiring) the room against short circuit and overload. A short circuit leads to the instantaneous occurrence of overcurrents in the power grid (currents by orders of magnitude higher than the operating currents).

Any overcurrent, and in apartment circuits it is 1.8-12.6 kAmps, according to the laws of physics, leads to the release of colossal thermal energy. This energy cannot be sustained by more than one household contact, and a flash or a so-called electric arc occurs at the point of a short circuit. If you do not quickly turn off the power supply to the emergency network, then the probability of a fire is very high, and even worse, a person will be hit by short-circuit overcurrents.

For protection against short circuits, namely for instant disconnection of the emergency network, automatic switches (circuit breakers) are used. Note that the disconnection does not occur instantly, but during the safe contact. This is less than 0.1 sec.

Circuit breaker and overload

The second function of the circuit breaker is overload protection. In there is a bimetallic plate (thermal release), overheating of which disconnects the electrical circuit from the power supply. Overheating of the plate occurs when the network is overloaded. It is clear that heating and, accordingly, disconnecting the circuit does not occur instantly, but after a while. Depending on the warm-up of the circuit breaker, this time can be less than a second or several tens of seconds.

We turn to the malfunctions of the electrician of the apartment.

Malfunction of the circuit breaker in the mains

Your circuit breaker periodically knocks out. The probabilistic reasons for this are as follows:

Short circuit in the circuit;
Network congestion;
Damage to wires intermittently leading to either a short circuit or overload.

First you need to diagnose the electrical network for overload and short circuit. If these malfunctions are not detected, and the machine is still turned off, then a malfunction of the circuit breaker itself is very likely.

Checking the circuit breaker

Do a basic check on the circuit breaker.

Disconnect the power supply;
Disable all circuit breakers;
Flip the cocking lever of the circuit breaker. It should turn on and off with a characteristic “click” sound.
If the click is not heard, the machine is faulty and requires replacement.
If there is a click, use a measuring device to measure the resistance between the terminals of the circuit breaker. When "on" machine resistance should be close to zero. When "off" machine resistance should be close to infinity.

However, even if the diagnostics of the machine showed that the machine is in good working order, this does not mean that the setting (thermal release) of the circuit breaker is serviceable.

Generally speaking, factory failure of circuit breakers is not uncommon and important. What can we say about the arising malfunctions of machines during operation.