APO: Active Safety for High-Voltage Systems

Electrification is advancing across all industries – from electric vehicles and charging infrastructure to energy storage, aerospace, and fuel cells. As a result, the demand for reliable protection mechanisms in high-voltage systems is increasing. With the new Pyrofuse-APO Series, Schurter launches a fuse technology that sets a new benchmark for safety.

Unlike conventional fuses, the APO Fuse operates actively. In the event of a short circuit or accident, the control unit sends a trigger signal to an integrated micro gas generator. Within milliseconds, the generator produces high pressure that drives a piston to mechanically sever the solid copper busbar. The resulting arc is safely suppressed in a dedicated extinguishing chamber. The outcome is a complete galvanic isolation in less than two milliseconds – with measured values as fast as 0.9 ms.

High Breaking Capacity
The APO Series is rated for operating voltages up to 1000 V and continuous currents up to 400 A. With an ultra-low internal resistance in the range of only a few dozen µOhms, power losses and temperature rise remain minimal. Its high breaking capacity ensures safe interruption even under extreme short-circuit conditions, while the fully encapsulated design prevents the release of gases or particles.

Maximum System Safety
This unique combination of speed, robustness, and efficiency guarantees maximum system safety. At the same time, the compact design allows for seamless integration into existing architectures and relieves downstream components such as contactors.

With the Pyrofuse-APO Series, Schurter strengthens its position as a technology partner for e-mobility and the energy transition. Whether in electric vehicles, aerospace applications, or stationary storage systems, the APO Fuse ensures that high-voltage systems remain reliably protected – even under the most demanding conditions.