How to choose solid-state relays when controlling a 230VAC heater using an STM32?
If you're controlling a 230VAC heater using an STM32 microcontroller , you’ll need a solid-state relay (SSR) that can safely switch high AC voltage and be triggered by the STM32’s logic-level output (usually 3.3V or 5V). Here's a tailored SSR selection guide for your application: Recommended SSR Specifications for Your Case Parameter Requirement Load Type Resistive (heater) Load Voltage 230VAC Load Current Choose SSR rated 1.5× to 2× heater current Control Signal Voltage 3.3V (from STM32) Output Type AC (Triac/SCR-based) Switching Feature Zero-crossing detection (minimizes inrush) Mounting Type Panel or DIN rail (based on enclosure) Isolation Opto-isolated input (essential) Cooling Heat sink if load current ≥10A Example SSR Models (Popular & Available) SSR Model Control Voltage Load Voltage Load Current Notes Omron G3NA-220B 5–24VDC 75–264VAC 20A Reliable, widely used Fotek SSR-25DA 3–32VDC 24–380VAC 25A Budget-friendly, opto-isolated Carlo Gavazzi RM1A2...