NH42400/4SZ Dual Power Automatic Transfer Switch (NH42SZ, PC level) Key benefits Continuous power supply: automatic detection and transfer between primary and backup sources helps maintain uninterrupted power for critical loads. Improved safety and fault prevention: mechanical and electrical interlocking prevents simultaneous source connection and reduces risk of short circuits; builtin protection functions add an extra layer of operational security. Durable, longlasting operation: stable internal design and smooth contact switching extend service life and reduce the need for frequent component replacement. Flexible functionality and expansion: modular design supports a variety of functional modules for and capacity upgrades, allowing the unit to adapt to changing system requirements. What this product does Automatically monitors two power sources and transfers load according to preset logic to ensure continuity of supply. Provides reliable switching with mechanical and electrical interlocks to prevent hazardous configurations during transfer events. Accepts additional modules to add features or integrate with control systems at PC level. Main specifications and compatibility Model: NH42400/4SZ Size designation: NH42400/4SZ (4pole configuration indicated by model code) Switch type: NH42SZ dual power automatic transfer switch (PC level) Design focus: automation, electrical and mechanical interlock protection, modular functional expansion Why customers choose this unit Ensures operational continuity for equipment that cannot tolerate unexpected power interruptions. Reduces operational risk by separating source controls mechanically and electrically during transfer. Allows phased upgrades or feature additions via plugin functional modules without replacing the entire switch. Typical applications Commercial buildings and emergency power systems where automatic switching keeps critical circuits energized during source loss. Industrial facilities and production lines that require reliable source transfer to avoid process downtime. Communication rooms, server closets, and control centers that need fast, reliable switching and modular integration at PC control level. Installation and maintenance notes Suitable for integration into existing electrical distribution systems matching the NH42400/4SZ size and 4pole configuration. Designed for straightforward installation and routine maintenance; modular structure simplifies replacement or addition of functional modules. Ensure installation and commissioning are performed by qualified electrical personnel in accordance with applicable local regulations and practices.