Content:
- What are the analogues?
- When is it rational to choose a differential machine?
- Criterias of choice
What are the analogues?
Short circuit protection functions and current overloads perform electrical machines (AB), which have long supplanted cork fuses from use. Leakage tripping is provided by products that have recently become an obligatory element of electrical networks, called residual current devices (
RCD). Recently, differential automata, which have protective functions, both against short circuits and against leakage currents. A person, especially not experienced in electrical engineering, sometimes cannot decide what to choose as protection electrical equipment of the electrical network, a differential circuit breaker or a combination of a circuit breaker and RCD.There is no definite answer to the question of which equipment to make a choice in, because both the difavtomat and the residual current device have both advantages and disadvantages. Ultimately, it all depends on the specific circumstances. In one of our articles, we considered the question, what to choose: differential machine or RCD.
When is it rational to choose a differential machine?
There are a number of factors in favor of installing an RCD, but one of the indisputable ones remains the most important advantages of choosing a difavtomat are saving space for installing equipment in switchboard. The high degree of energy saturation of the housing of a modern person requires an appropriate level of protection equipment from short-circuit currents, overloads in power, as well as reliable electrical safety. Particular attention should be paid to the arrangement and selection of current leakage protection intended for a washing machine, electric boiler, water heater, bathhouse, bathroom and pump.
When designing an electrical network diagram, it is necessary to take into account that an RCD connected to the circuit of each of the above consumers, it is necessary to provide protection against short circuit and overcurrent, that is, for each RCD, an automatic installation will be required switch. As a result, it may turn out that there will not be enough space for this. din rail shield. The choice of a difavtovomat, combining the functions of AB and RCD, allows more rational use of the electrical panel.
Criterias of choice
Having given preference to the difavtomat, it is necessary to carefully consider the process of its selection. Initially, it is necessary to familiarize yourself with the performance of the product.
Rated voltage and phase. It is not difficult to choose the correct differential automaton in accordance with the required parameters. Devices designed for operation in a single-phase network (220 V) are equipped with three connection terminals, difavtomats for three-phase networks (380 V) are equipped with four poles. The rated operating voltage is indicated in the passport and marked on the product body.
Current rating and characteristics. In order to ensure high-quality operation of the differential machine, it is important to choose the correct current rating and characteristic. Information about these parameters is indicated by a letter of the Latin alphabet and a number, for example, C25, which means a device of characteristic C, at a rated operating current of 25 A. The most popular difavtomats for apartments and private houses are products of the characteristics of C. When choosing a power differential machine, it is recommended to adhere to the values indicated in the table:
Leakage current. It is indicated by a delta symbol with a number corresponding to the rated leakage current in milliamperes. The data in the second table will help you to choose the correct leakage current device:
Important! For a water heater, washing machine, bathroom or bath, you need to choose an apparatus that works at 10 mA. On the group line, it is enough to select a characteristic of 30 mA, if you decide divide the wiring into groups. To enter a private house, to protect against fire, it is recommended to install a difavtomat for 300 mA, and in apartments it is enough to use an apparatus designed for 100 mA.
RCD class. RCDs built into the differential machine are divided into two classes:
- A - triggered by DC leakage. To connect consumer electronics consumers to the network, select an RCD of this class
- AC - turn off the difavtomat when AC leaks appear in the network and on electrical equipment.
Neutral conductor breakage protection. Some difavtomats are equipped with blocks that disconnect consumers when break of neutral wire. When arranging the protection of equipment against current leaks, it is advisable to choose just such a product. Another important characteristic is shutdown time (denoted as Tn). It should not be more than 0.3 s.
For a person who is not sure that he will be able to choose a difavtomat himself, it is recommended to make an acquisition in commercial establishments with a high reputation, in which you should seek the help of qualified consultant. With him you can discuss the issues of an acceptable price and in favor of which manufacturer of differential machines you should give your choice.
Finally, we recommend watching a useful video on the topic:
So we examined how to choose a difavtomat according to power and leakage current. We hope that the information provided has helped you to understand the choice of a suitable differential machine for a house, summer house or apartment!
We also recommend reading:
- Top circuit breaker manufacturers
- How to choose an RCD for an apartment
- Connecting a difavtomat with your own hands
