Square Peg in Round Hole

Our CTO Jens Schroer was invited to Intertek to present our certification journey of Blixt Zero, the world’s first miniature solid state circuit breaker. And why would we even need to have a fully digital circuit breaker?

As most of you already know, a traditional circuit breaker is a mechanical device. Its sole purpose is to protect against over-currents (short circuits and similar). At best it responds to a fault within 1ms, which is far too slow to ensure electrical safety, in particular for DC. Remote control and monitoring is only available via additional external devices, other issues include mechanical wear and arcing. The only good news is that there are dedicated IEC standards for certification.

So how could we certify an electronic device according to mechanical standards?

Together with Intertek we worked intensely to find a short term work-around by using a different standard that would still allow us to operate it as a circuit breaker, while we joined the IEC working group PT 60947-10 for the upcoming new solid state breaker standard at the same time. During the journey we faced several design challenges – insulation and creepage distances, thermal management, form factor DIN rail, just to mention a few. But hard work paid off! The IEC certification was finally approved in September 2021, meaning that the Blixt Zero is proven to be safe to operate, can be installed in a distribution panel and meets the required EMC standards.

Now we are looking forward to the new solid state circuit breaker standard being released, which will enable us to roll-out our next generation SSCBs faster, cheaper and with less grey hairs!