M3 and M21 Fused Switches: Compact, Safe and Efficient Solutions for Low Voltage

Fused switches are essential in low-voltage installations as they combine isolation and protection in a single device. In sectors such as industry, commercial buildings and power electronics, having compact, reliable and easy-to-maintain solutions helps optimise both safety and service continuity. In this context, Telergon’s M3 and M21 series provide a comprehensive solution for different levels of demand.

What is a fused switch and what is it used for?

A fused switch is a device that combines the function of current interruption (isolation) with protection against overloads and short circuits by means of fuses. It is used to protect electrical installations and ensure safe disconnection.

M3 and M21 fused switches: a complete solution for protection and isolation in low voltage

They offer a robust, safe and versatile solution for the protection and disconnection of low-voltage electrical installations in industrial and commercial environments worldwide. This range integrates compact and modular equipment that ensures reliable fuse-based disconnection, complying with the main international standards.
Designed to cover a wide range of requirements, these switches are available from 30A to 800A and are compatible with different fuse types (Class J, NH, BS, NFC), allowing adaptation to multiple regulations and applications across different markets.

Among their main features are:

• High breaking capacity, with a short-circuit rating of up to 200kA, ensuring maximum protection under demanding conditions.
• Double-break contact system, ensuring complete and safe disconnection of the fuse.
• Load switching capability, allowing safe operation without critical interruptions.
• Flexible configurations, with 2, 3 and 4-pole versions.
• Options for direct operation or external handle, with front or side mounting and high protection ratings (up to IP65 / NEMA 4X).

What applications are fused switches used for?

The use of fused switches is essential in environments where safety, reliability and continuity of power supply are priorities.

Their main applications include:
• Industrial distribution boards and control panels, where they ensure the protection of critical electrical equipment and facilitate safe maintenance tasks.
• Electrical installations in commercial buildings, optimising power distribution and improving installation safety.
• Energy infrastructure and utilities, such as distribution networks, where high breaking capacity and maximum reliability are required.
• OEM applications (equipment manufacturers), including HVAC systems, industrial machinery and automation solutions, where they are integrated as an essential protection element.
• Power electronics, especially in auxiliary service panels, protecting sensitive circuits against electrical faults.

Thanks to their robust design and versatility, fused switches are an efficient option for improving the protection of industrial and commercial electrical installations, reducing risks and ensuring operational continuity.

Enclosed solutions: enhanced integration and protection

In addition, Telergon’s range includes enclosed fused switch disconnectors, designed to further simplify installation.
These solutions are available from 63A to 800A, in 3P and 3P+N versions, within metal and polyester enclosures with an IP65 protection rating.

The main advantages of enclosed fused switches are:
• Integration of isolation and protection in a single unit
• Enhanced safety in demanding environments
• Reduced installation time
• Compact and robust format

Certified for Global Markets

• UL 98
• CSA 22.2 No. 4
• IEC 60947-3
• UL Guide WHTY listed
• File E363652

The M3 and M21 series from Telergon, together with their enclosed solutions, provide a complete range of fused switches tailored to the current needs of the electrical sector. From compact applications to highly demanding industrial environments, these solutions ensure safety, efficiency and reliability.