Power disconnector LN4, 3-pole 1600A LN4-1600-I 112015

Protection of High-Current Circuits

In distribution circuits where current flow reaches 1600 A, it is crucial to use a device that not only safely disconnects the circuit but also ensures reliable isolation under fault conditions. The LN4-1600-I power disconnector is a device dedicated to installations requiring high continuous current, offering short-circuit withstand strength up to 25 kA (Icw) and conditional short-circuit current up to 100 kA (Iq). Thanks to this, the element effectively protects the installation against the effects of short circuits, acting as the main separation point or maintenance disconnector in power supply systems.

The device features a three-pole construction and is designed for operation at voltages up to 690 V AC. This version uses a lever as the operating element, facilitating manual control, while the built-in locking mechanism guarantees maintenance of the switching position even in the presence of vibrations or shocks occurring in distribution boards. It is worth noting that although the device does not come with a factory-installed motor drive, the design allows for its installation as an optional accessory, opening the way for automation of the disconnection process without the need to replace the entire device.

Mounting Flexibility and Functional Expansion

Mounting this disconnector requires precision – it is intended for permanent installation in distribution boards via bolted (screw) connections, ensuring low transition resistance at such high currents. The device is not designed for central front mounting or 4-hole panel mounting, which means that appropriate space within the cabinet must be planned according to its dimensions: width 210 mm, height 207 mm, and depth 401 mm. The IP20 protection rating on the front side protects against accidental contact with live parts by adults but requires installation inside a protected enclosure within the switchgear.

For installers, the possibility of expanding the device's functions is important:

• Optional motor drive: Enables remote control of the disconnector, which is critical in building automation or industrial control systems.
• Undervoltage release: Available as an accessory, it allows automatic disconnection of the device in case of voltage loss or overvoltage.
• Accessory compatibility: The device uses a common range of accessories for the LZM/LN and NZM/N series, facilitating the selection of auxiliary contacts (from the RMQ panel), mechanical locks, or door drives.

It should be noted that the device does not come with factory-installed auxiliary contacts (neither normally open nor normally closed), so their addition requires purchasing appropriate modules. This allows customization of the number of feedback signals according to the specifics of the installation monitoring system.

Application and Operating Conditions

This disconnector is ideally suited as a main component in power supply systems for high-power motors (up to 800 kW at AC-23) and in circuits requiring safe disconnection during maintenance work. Its characteristics allow operation in ambient temperatures from -25°C to +70°C, and electrical parameters remain stable even at temperatures up to 50°C without the need to adjust rated values.

Key applications include:

• Main disconnectors: For safe disconnection of power to entire sections of switchgear.
• Maintenance disconnectors: Provide a visible isolation gap essential for maintenance work in accordance with HSE regulations.
• Emergency switches: In configurations with appropriate accessories, they can function as a "STOP" button for large machines.

The device is not intended for use as a reversing switch or as a safety disconnector under machine standards without additional locking accessories. Its gray enclosure and compact dimensions allow efficient use of spacewithin the distribution cabinet while maintaining the high electrical safety standards required for high-power industrial installations. It is important to remember the continuous current rating of 1600 A and the maximum operating voltage of 690 V AC – these are the decisive parameters for selecting this model for a specific circuit. The lever mechanism with a lock ensures reliable operation even in the harsh environmental conditions typical of production halls or industrial zones.