Arc Fault Circuit Interrupter (AFCI) solution
Build your own arc fault detection mechanism with edge AI.
As the market evolves, we see new and different types of applications emerging that request more & more innovations to protect against electrical arcs: solar panels, batteries, power tools, e-bikes and so on.
Rule-based algorithms exist today to improve the safety of electrical installations, but their adaptability is limited, and they generate a large number of false positives, thus reducing machine yield. There are also Cloud-based AI solutions, which offer greater accuracy but come with concerns about latency and privacy.
This is where edge AI solutions offer the ideal compromise. Requiring no connectivity or external processing, these solutions enable instant detection and response, while eliminating privacy and security concerns since data is processed locally on devices. Their ability to continuously learn and adapt to different environments also reduces false positive rate and improves efficiency.
In this use case, we will show you how you can simply build your own arc detection mechanism with edge AI and STM32!
Approach
Our approach was as follows:
- We used a custom arc fault circuit interrupter (AFCI) board with an STM32G4 at the heart of it for this demonstration.
- We first collected the normal operating data from the setup, totaling around 1000 signals.
- Then, we gathered arc fault data, also around 1000 signals.
- Both sets of signals were imported into a classification project within NanoEdge AI Studio.
- The tool then generated the best AI library for this project and we integrated it into the code to monitor the current and trigger an alert if an arc is detected.
Sensor
Data
Length data 2048 * 1 axis
Data rate 150 kHz
Results
2 classes (no arc & arc fault):
100% accuracy, 16.7 Kbytes RAM, 0.5 Kbytes Flash



A green point means we are able to correctly predict if the finish will pass a visual inspection or not.
A red point means we were incorrect.
Resources
Model created with NanoEdge AI Studio
A free AutoML software for adding AI to embedded projects, guiding users step by step to easily find the optimal AI model for their requirements.
The STM32 family of 32-bit microcontrollers based on the Arm Cortex®-M processor is designed to offer new degrees of freedom to MCU users. It offers products combining very high performance, real-time capabilities, digital signal processing, low-power / low-voltage operation, and connectivity, while maintaining full integration and ease of development.