AMI has developed and patented an optical switching technology that provides a safer and more reliable method for detecting blown fuses in safety-critical systems. The solution replaces traditional electrical detection methods with a mechanically actuated optical approach directly linked to fuse operation.

Conventional blown fuse detection relies on low-voltage electrical microswitches, which can be vulnerable to high-voltage exposure, electrical noise, and voltage drops, especially in medium-voltage environments. These limitations can lead to reduced reliability and increased safety risks.

The patented optical switching mechanism maintains a continuous fiber optic loop during normal operation. When a fuse operates, a mechanical actuator physically blocks the optical path, interrupting the optical signal immediately. This direct, hardware-level response ensures a deterministic and fail-safe indication of fuse operation.

By directly tying the optical signal state to the fuse’s physical condition, the system eliminates the need for software, electronic sensing, or secondary electrical circuits. This technology is now part of AMI’s Safety by Design approach, reinforcing a commitment to hardware-enforced safety in industrial applications.