How to connect RCD? RCD connection diagram in the apartment

The use of electricity at the dawn of the 20th century opened up unprecedented opportunities for mankind. Progress in the development of civilization has ultimately led to an incredible improvement in the life of every modern person. Electricity began to perform many routine operations for people and made life in a civilized society as comfortable as possible. Although it brought with it certain inconveniences in the form of increased attention to their own safety.

Electric current is a dangerous assistant

As far as electricity has become useful in the economic and household arrangement of people's lives, it has also brought a lot of problems for their health. A very necessary assistant - electric current - has become a source of danger and a threat to the life and health of users of electrical appliances, power tools and household appliances. Of course, with a careless attitude towards him. Therefore, many devices and devices were created and developed to minimize the trouble when using electricity. One such device is a residual current device (RCD). How to connect an RCD will be discussed below.

Methodology and methods of protection

The rules for the operation of electrical installations (PUE), which are a reference book for specialists working with electricity, provide strict and clear methods for protecting a person from the negative effects of electric current on his health. The method of such protection is based on the use of modern effective insulating materials, instruments and devices that control the quality of power networks, the maximum current and voltage limits, as well as the rules of conduct for the people themselves working with electrical equipment.

The main way to protect against a "dangerous" assistant is to properly ground electrical appliances and power networks. Such protection reduces the damage from the effects of electric current to human health to a minimum. But there are moments that define other methods of protection. For example, leakage current, which is imperceptible to a person, but at the same time can cause great trouble.

The only task is to find the fugitive

Current flowing through old or damaged wire insulation can become a source of ignition in an apartment or in a country house due to overheating of electrical wires. And also to hit a person during the operation of electrical household appliances in conditions of high humidity and caught in the current spreading zone.

This can happen when working with household appliances such as boilers, washing machines, dishwashers, refrigerators, and so on. Here, devices are used to protect a person and his home from the negative effects of electric current.

To control leakage currents - and they, unfortunately, are present in any electrical network - a residual current device is designed. RCD connection is possible both in rooms equipped with protective grounding and in non-equipped ones.

The device device for protective shutdown

The device is nothing more than an ordinary automatic relay, the circuit of which is designed to prevent current imbalances between the conductor supplying current through the phase wire and zero over the specified values. The design of the device is very similar to a circuit breaker. Each device is equipped with a test button, which gives the consumer an idea of ​​its performance. By the way, the test mode present in this device visually distinguishes it from circuit breakers.

The use of these devices is becoming more common in modern homes and apartments, not to mention industrial facilities. But for this device to work and truly protect, you need to know very well how to connect an RCD. There are certain rules and methods for connecting it, which must be followed steadily. It is possible and necessary to protect your house or apartment from fire, and people from negative consequences due to exposure to electric current. And only with perfect knowledge of how to properly connect the RCD, this is very easy to achieve.

Types and characteristics of RCD

Residual current devices are available in several types, depending on the requirements for their use. Household RCDs are capable of operating both in networks with a voltage of 220 volts and in networks of 380 volts. Along with the task of controlling the magnitude of the leakage current, the device also monitors the current that passes through its contacts - these critical values ​​are printed directly on the body of the device.

To answer the question of how to properly connect an RCD, it is necessary to clearly navigate the data printed on the device and indicating all its characteristics. Connection terminals - both input and output - are marked with letters or schematically. The rated current and operating current, as well as the rated voltage for which the device is designed, are indicated. The task of a specialist (and it is desirable to connect the device to a professional electrician) is to correctly select the device and clearly know how to connect the RCD. After all, an incorrect definition of the task assigned to the device will not improve protection at all, but, on the contrary, can have a negative impact on home security.

General principles of device operation

The device compares the currents flowing through it to electrical appliances and, in the event of a difference between the forward and reverse current, immediately opens the circuit. It is set to zero current difference between "phase" and "zero". In the event of damage to the insulation of the wires or their dilapidation, which allows current to penetrate through the materials of walls and ceilings, as well as through conductive media from the phase wire to zero or to the "ground", the same difference occurs that causes the device to work and open the circuit. This is the only task of the device, with which he copes with "excellent", if properly selected and connected.

Device classification

It should be noted that the device itself is not an effective protection for all occasions. It will be able to work alone, but this device will not be able to protect against short circuit currents or overload currents. Therefore, a circuit breaker is always installed in pair with it. Many diagrams scattered around the Internet describe how to connect an RCD and an automaton. One thing can be said - the RCD is always connected in front of the machine.

RCDs are divided into five classes, which, in fact, perform specific tasks:

• AC - protects against alternating current leakage;
• A - from alternating and direct impulse current;
• B - industrial RAM;
• S and G - used in fire safety schemes.

Devices are made both in the form of electromechanical devices, and can be electronic. About the second, we can say that they need to work. Some are designed to work from the built-in power source, others work from the same network.

Selection of a device for an apartment and a summer residence

The very formulation of the question may seem incorrect. But this is only a superficial view. Because, knowing how to connect an RCD in an apartment, you can over- or undercalculate something when installing it in the country. After all, the electrical networks themselves at these facilities are quite different both in terms of load and performance. Therefore, when selecting a device, it is clearly necessary to know how many current consumers the installed device should protect and what quality the existing electrical wiring is. As a result, the method of how to connect the RCD in the country will be somewhat different from its "apartment" scheme. However, only by choosing the number of devices and their class.

If the apartment has - let's call them that - several groups of consumers, and its quadrature is large enough, and the wiring is done with high quality and not so long ago, then installing one RCD will be correct in the case when there is no space in the switchboard. Because it - in case of operation - will de-energize the entire apartment completely. The scheme for connecting the RCD in the apartment will be somewhat different than when installing the device in the country.

It is desirable to have an RCD on each group. This will be the best option. A group including bath-kitchen appliances will need a device designed to operate at a leakage current of 10 mA, for the rest, a 30 mA device is also suitable. And according to the class of the device, it is desirable to install an RCD of type A. But, knowing modern apartments, you can immediately say that for most of them an AC class device is suitable, which can already create a lot of problems - old wiring, a humid environment will force you to constantly run to turn it on . The way out of this situation can be considered the installation of an RCD on each outlet. This will ensure the protection of any household appliance included in it, and its immediate shutdown in case of problems, rather than de-energizing the entire apartment.

How to connect an RCD in the country? At the cottage, the situation is slightly different. Less household appliances - perhaps on the contrary, but this is not common - wiring is “lighter”, and therefore it is possible to install AC class devices at 30 mA here. But also necessarily in tandem with a circuit breaker.

Device connection diagrams

Depending on the tasks assigned to the device by the number of current consumers and the quality of the wiring, you can clearly define the device itself and its connection diagrams. But you still need to firmly understand how to properly connect the RCD. The scheme of such a connection differs in only one thing - the choice of the number of groups protected by the installed device. Let's say there is only one group. Everything is simple here - just know how to connect the RCD and the machine. If the protection method is chosen by groups of current consumers, then the connection diagram consists of several devices that are installed on each group. The RCD is connected to the circuit directly behind the meter.

What RCD does not protect against?

It is worth noting one important point that was mentioned above - the RCD only protects against current leakage. Yes, weak and old wiring will trigger the appliance and possibly prevent a fire. But it will not save you from a permanent power outage in an apartment or in a country house. If it is not possible to replace the wires, then it is pointless to install an RCD.

The same is true if there is an overload in the circuit. Either the TV is broken, or the contact in the light bulb is bad - the RCD does not follow this. Especially when a short circuit occurs, the device is powerless. In this case, only a circuit breaker, which must be installed after the RCD, can protect people and other devices.

The right choice of reliable protection

After reading this material and "digging" in the World Wide Web, anyone can draw a conclusion for themselves, does he know how to connect an RCD? And the question of whether such protection is needed in his apartment or at his dacha remains open. If the wiring allows, there is a place for installation, then this method of protection will only improve security. In cases where the wiring is old, you have to choose from two options - either replace the wiring, or refuse to use the residual current device. Nothing else is given.

It is worth noting that the statement about the installation of an RCD without grounding is unacceptable and useless, erroneous on all counts. It is the principle of operation of leakage current protection that allows the device to provide normal protection in rooms where there is no grounding. In the end, the choice is up to the person and his desire to live in a safe, but no less comfortable home.