ABB FN Switch

Description

This device is a Load Break Switch, also known as a Switch Disconnector. It’s designed to safely interrupt and isolate electrical loads—particularly useful in motor control centers, capacitor banks, and distribution panels. ABB’s version commonly aligns with their NAL/NALF indoor air-insulated models.
ABB Group

Specifications

Based on ABB’s NAL/NALF indoor load break switch series:

• Voltage: Up to 36 kV (medium voltage indoor use)

• Current: Up to 1,250 A

• Rated short-circuit withstand: Typically up to ~31.5 kA for 1 second

• Configurations: 3-pole with modular structure
  ABB GroupJGGY Electrical

Features

• Compact, modular design suitable for switchgear and compact substations

• High number of switching operations at rated current

• Optional accessories include shunt trip, motor operators, auxiliary contacts, and earthing switches

• Can be combined with current-limiting fuses for full overcurrent protection (e.g., NALF version)

• Capable of handling frequent switching and fault condition brief disconnection
  ABB GroupJGGY Electrical

Applications

• Indoor medium voltage switchgear panels

• Transformer protection via switch-fuse combination

• Capacitor bank switching, especially in APFC systems

• Compact substations, motor control centers, and industrial distribution boards
  ABB Group+1

Advantages

• Safely handles load currents, including fault conditions when used with fuses

• Highly reliable for frequent operation

• Space-efficient, flexible configuration

• Facilitates visible isolation and safe maintenance

Disadvantages

• Manual operation only—no automatic switching

• Higher voltage-rated models may require specialized installation

• On its own, it doesn’t provide full overcurrent protection unless paired with fuses or breakers