Katko 63A Changeover

Katko 63A Changeover Switch: Reliable Manual Transfer Switching

The Katko 63A Changeover Switch is a load break switch engineered to make, carry, and break currents under normal circuit conditions, including specified overloads . It allows operators to manually transfer loads between two separate power supplies, such as a mains supply and a generator, ensuring continuity of power in critical applications. The distinct “1-0-2” switching positions provide clear selection between source 1, off, and source 2, while a mechanical interlock prevents the dangerous condition of both sources being connected simultaneously . Built to stringent IEC 60947-3 standards, this switch guarantees high performance and safety in industrial environments .

Katko 63A Changeover Switch: Key Specifications

Katko 63A Changeover Switch: Models and Configurations

The 63A changeover switch is available in several configurations to suit different installation requirements:

• 3-Pole (TP) Models: KU 363N for 3-phase systems without neutral switching

• 4-Pole (TPN) Models: KU 463 for 3-phase systems with neutral switching, ideal for generator changeovers

• Open Style (IP20): For panel mounting on DIN rail or screw mounting within control cabinets

• Enclosed Version (IP65): Complete with dust-tight and water-resistant enclosure, suitable for outdoor installation and harsh environments

Katko 63A Changeover Switch: Advanced Safety and Design

The Katko changeover switch is built with several key features that enhance safety and longevity:

• Silver Contact Technology: The switch utilizes robust silver-alloy contacts, which are excellent conductors and naturally resistant to corrosion and arc erosion. This ensures low contact resistance, reduces heat generation, and guarantees a long operational life even under frequent use .

• 1-0-2 Switching Logic: The clearly defined rotary positions allow for safe selection between power sources. The central ‘0’ position provides a positive off state, ensuring complete isolation of the load during maintenance or source changeover .

• Padlockable Handle: The ergonomic handle features a mechanism that can be padlocked, typically in the ‘OFF’ position, to secure the circuit during maintenance and prevent unauthorized operation, complying with essential safety lockout/tagout procedures .

• Mechanical Interlock: A built-in interlock mechanism physically prevents the switch from connecting both power sources at the same time, which could cause a dangerous short circuit or backfeed .

• Versatile Installation: The modular KU series design allows for easy mounting on standard DIN rails within control panels, saving valuable space. For outdoor or harsh environments, enclosed versions with an IP65-rated polycarbonate enclosure offer protection against dust and water jets .

Katko 63A Changeover Switch: Applications

This robust changeover switch is essential for a wide variety of industrial, commercial, and infrastructure applications:

• Generator Changeover Systems: The most common application, allowing safe and reliable switching between the mains utility supply and a standby generator in commercial buildings, data centers, and large residences .

• Industrial Machinery: For switching power sources or operating modes on equipment like pumps, conveyors, and compressors, particularly where redundancy is required.

• Main Power Distribution: Used as a main switch or changeover in distribution boards to select between different incoming feeders.

• Motor Control: Can function as a motor disconnect switch, with power ratings suitable for controlling 3‑phase motors up to 22kW (AC-23A) .

• Bypass Applications: In uninterruptible power supply (UPS) systems or HVAC systems, allowing equipment to be bypassed for maintenance without interrupting power.

Katko 63A Changeover Switch: Installation and Safety Notes

Installation must be performed by a qualified electrician in accordance with local regulations (such as BS 7671) and the manufacturer’s instructions:

• The switch is typically supplied as an open device for panel mounting on DIN rail. If an IP65 enclosure is required for outdoor or harsh environments, ensure the specified model is an enclosed unit .

• For open devices, appropriate clearances must be maintained within the control panel to prevent accidental contact with live parts.

• Cables must be terminated securely with the correct torque (2.5 Nm) to ensure reliable connections .

• Important Note: Aluminium cables cannot be connected directly to the switch terminals. For aluminium cable connections, a bi-metal cable connector must be used .

• Always ensure the switch is operated in a no-load or light-load condition unless it is specifically rated for on-load switching (which the 63A AC ratings confirm it is).

• The switch is padlockable only in the ‘0’ (OFF) position. Never attempt to bypass this safety feature.

Katko 63A Changeover Switch: Quality Assurance

The Katko 63A Changeover Switch is manufactured to meet rigorous international standards, including IEC 60947-3, ensuring thorough testing for electrical safety and performance . Designed and manufactured in Finland, Katko switches reflect decades of industrial experience and are trusted wherever reliability cannot be compromised. With a mechanical endurance of 50,000 operations and robust construction, this switch provides years of dependable service in the most demanding environments .