Fuse switches

The fuse switch is one of the basic elements protecting electrical installations. This small size accessory is able to protect the network, e.g. against the dangerous effects of short circuits and overloads. These in extreme cases can even lead to a fire. Switch disconnectors not only protect installations, but also all devices and equipment directly connected to them. There are several types of this product on the market. They differ in the possibilities of application and the specificity of operation.

Fuse Switches – definition

Fuse-switches (from English fuse-switch) are a special type of electrical equipment equipped with replaceable fuse-links. They are installed to protect electrical installations and the energy receivers connected to them. In the fuse switch, a mechanical connection of the switch and the fuse holder is used, in which the fuses are placed. The device allows you to replace a burnt insert without the risk of touching live equipment. There is also no need to use a fuse head, and the correct contact of the link is ensured by a properly designed set of spring terminals.

Fuse switch disconnectors are used in distribution networks, main switchboards in multi-family buildings, in industrial power installations and many others. The use of fuse links makes the device work well, for example, as pre-meter protection or in the protection of surge arresters.

How do fuse switch disconnectors work?

The operation of fuse switch disconnectors is based on fusible elements mounted in the housing, commonly referred to as fuses. When an overvoltage or short circuit occurs and the hardware detects this condition, the element dissolves. This in turn leads to an immediate disconnection of electricity. The disconnector even reacts at the same moment when the network fails. A blown fuse can be replaced with the entire insert to which it is attached. Thanks to this, the equipment is able to continue to protect the installation and there is no need to replace it with a new one and thus expose itself to additional costs.

Types of fuse switch disconnectors

Fuse switch disconnectors are divided into classic and so-called slatted. The latter have fuse links in a vertical arrangement (traditional types of equipment have inserts in a horizontal arrangement) intended for mounting directly on busbars.

 In addition, among the fuse switch disconnectors, the following can be distinguished:

• 3P models – so-called three-pole devices, i.e. cooperating with three-phase electrical installations.
• 1P models – less popular, slightly simpler switch disconnectors adapted to protect single-phase electrical installations. They cut off the power supply only in the selected section;
• 2P models – very similar to 1P switch-disconnectors, but they cut off the current in the entire electrical installation;
• NH models – the most classic switch disconnectors adapted to be mounted in a horizontal arrangement. They can be found, for example, in home installations, in various types of electric motors, and recently their importance has increased, for example, due to the protection of photovoltaic panels with them;
• models with a movable cover - a special type of disconnectors equipped with a movable cover, which facilitates the replacement of the fuse-link with the melted fuse. It is possible to install a new insert without having to disconnect the entire installation.

There are also special fuse switch disconnectors adapted to work with four-pole installations. They are used for more extensive electrical networks supporting a large number of receivers and equipment requiring large amounts of energy.

Fuse switches vs switch disconnectors

Fuse switches are often confused with switch disconnectors. The latter, however, are slightly different in terms of electrical equipment. They are also used to protect the network against the negative effects of overvoltages or short circuits. However, the switch-disconnector is current-carrying under rated conditions. What's more – it is also capable of this in the event of a failure for a certain period of time. In such a situation, this equipment is responsible for the efficient supply of electricity to the main part of the installation circuit. Its second function is to isolate the system. In other words – this disconnector creates a safe insulating gap, which protects against possible electric shock. However, this only applies to high-voltage systems.

Most switch disconnectors are designed to be powered both “from above”and”from below”. In addition, they provide the possibility of sealing in the on and off position, also without a fuse link installed. High-class disconnectors of this type enable selective cooperation with overcurrent circuit breakers.

Fuse switch disconnectors in the el12 store's offer

In the el12 store we have a wide selection of fuse switch disconnectors adapted for installation in various types of electrical installations. We offer 1P, 3P, 2P and 4P models. We sell accessories only from reputable manufacturers, e.g. ABB, Apator, Eaton, ETI Polam, Hager, Legrand, Tehalit and Schnerider Electric. We enable the selection of disconnectors not only in terms of the number of supported poles, but also taking into account the rated voltage under which the given models operate. There are 230V, 400V, 440V, 500V, 600V, 690V, 750V and 1000V models. The store's offer also includes switch disconnectors. 

Fuse switches purchased in our online store are delivered to the address indicated by the customer within a maximum of three working days. The execution of the order may be extended if the product is not currently in our warehouses. At that time, the period of finalizing purchases may take up to several weeks. Information about the approximate delivery time of the fuses can be found on the catalog of each product, just below the technical specification.