Circuit breakers and switch disconnectors

Compact circuit breakers and disconnectors - essential elements of electrical installations

In modern electrical installations   Circuit breakers and switch disconnectors play a key role in ensuring safety and reliability . These small but extremely important devices are the first line of defense against overloads and short circuits. In our daily practice, we see how important it is to properly select these elements.

Onninen's range of circuit breakers and switch disconnectors includes renowned brands such as Eaton, Legrand, Eti, Schneider Electric and Hager. Each of them offers solutions tailored to the various needs of customers. We are often asked about the differences between the individual types of devices.

Types of circuit breakers and switch disconnectors

Our assortment includes various types of devices:

• Power circuit breakers with thermal-magnetic release
• Differential circuit breakers
• Isolating switches
• 3-pole and 4-pole power switches
• Main switches and switch disconnectors prod

Power switches with a thermal-magnetic release are the basic protection against overloads and short circuits . They operate on the principle of detecting a temperature increase or a sudden increase in current intensity. In turn, differential circuit breakers protect against electric shock by detecting the difference in current flowing in and out of the circuit.

Isolating switches are used to safely disconnect circuits from voltage. This is particularly important during maintenance work. Recently, in a project for a large shopping center, we used isolating switches to separate individual sections of the installation.

Criteria for selecting circuit breakers and switch disconnectors

Choosing the right device depends on many factors. Key parameters include:

• Rated current
• Nominal voltage
• Short-circuit capacity
• Number of poles
• Trigger Characteristics

In the case of office reorganization, we most often choose circuit breakers with a rated current of 16A or 20A . For lighting circuits, 10A circuit breakers work well. In industrial installations, on the other hand, we often reach for 3-pole power disconnectors with higher rated current values.

Many customers ask us about the differences between 3- and 4-pole switches. The former are used in three-phase networks without a neutral wire, the latter - when a neutral wire is present. In our practice, we more often encounter the use of 4-pole switches.

Onninen recommends paying special attention to the short-circuit capacity of circuit breakers.   This parameter specifies the maximum short circuit current that the device can safely interrupt . In residential buildings, 6kA is usually sufficient, but industrial facilities often require values of 10kA or higher.

Innovations in the field of compact circuit breakers and disconnectors

The development of technology does not bypass the electrical industry. A novelty is circuit breakers with surge releases, which react to a sudden increase in voltage. This is an additional protection against overvoltages in the network. Combination circuit breakers, combining the functions of an overcurrent and differential circuit breaker, are also becoming increasingly popular.

Our experience shows that   investment in modern solutions translates into increased reliability and safety of the installation . An example is the recent modernization of the production line in a furniture factory, where the use of switches with Modbus communication allowed for remote monitoring of the status of protections.

Onninen also offers accessories for circuit breakers and disconnectors, such as metal extensions or bellows valves. These elements facilitate the installation and operation of devices in hard-to-reach places. We often use them in high-density switchboards.

Selecting the right circuit breakers and switch disconnectors is a key element in designing a safe and reliable electrical installation. At Onninen, we offer not only a wide range of products, but also expert advice on their selection and application. We invite you to contact our specialists who will help you choose the optimal solutions for each project.