The first circuit breaker for industrial DC-applications

DC applications are increasing in importance in different industrial sectors, for example automation, robotics and industrial building technology. The use of higher DC voltages between DC 450 and 750 V (nominal voltage DC 650 V) reduces energy losses, allows smaller cable cross-sections and creates more flexible network architectures.
Relevant standards and customers also require reliable and safe protection against harmful overcurrents. Currently, there only complex or inadequate solutions are available. With the 8365-T circuit breaker, E-T-A is the first manufacturer to offer a compact and powerful solution for overcurrent protection up to DC 800 V.

Unlike many previous DC protection solutions, the 8365-T only requires one switching pole for DC 400 V and eliminates the need for a complex series connection of several circuit breakers. This significantly reduces control cabinet space requirements and simplifies the design. This results in lower system costs and more predictable performance.

With up to 53 % less power loss than conventional thermal-magnetic circuit breakers, the 8365-T also delivers strong results in terms of energy efficiency. Less heat loss means less cooling, which improves the overall balance of energy-intensive systems.

The circuit breaker reliably operates in a wide temperature range from -40 °C to +85 °C. Thanks to the hydraulic-magnetic operating principle, the tripping characteristic remains stable, regardless of the external conditions. This makes it the ideal choice for applications with variable ambient conditions, e.g. outdoors or in machines with high intrinsic heat.

An 8365-T with pulse-delayed characteristic is the best choice for protecting capacitive loads like switch mode power supplies or DC/DC converters. This characteristic curve tolerates  "inrush currents" (high currents that occur when switching on) - without any additional pre-charging electronics. This simplifies integration considerably and helps reduce components and wiring.

From the DC 24 V control level and the DC 400 V supply network to robotics and industrial lighting: The 8365-T circuit breaker fits seamlessly into existing DC concepts and unlocks new possibilities for a space-saving and modular system architecture.