Differences

This shows you the differences between two versions of the page.

--- actor:ssr_moduls [2026/05/14 22:22] – vamsan
+++ actor:ssr_moduls [2026/05/14 22:25] (current) – vamsan
@@ Line 20: / Line 20: @@
 A Zero-Cross function is a feature in AC Solid State Relays (SSRs) that synchronizes switching. It ensures the relay opens the circuit precisely when the AC voltage sine wave crosses zero volts, minimizing electrical noise and stress. In typical household outlets, AC voltage oscillates smoothly between positive and negative peaks, such as +325V and -325V, at 50 or 60 Hz.
-If your Arduino sends an "ON" signal at the peak of the wave (+230V) without a Zero-Cross function:
+If your Arduino sends an "ON" signal at the peak of the wave (+230V) //without a Zero-Cross function//:
   * A massive, instantaneous rush of current enters the load.
   * This generates Electromagnetic Interference (EMI) and radio noise.
   * It creates severe electrical stress on the component, shortening its lifespan.
+**The Solution: How the Zero-Cross Circuit Works**
+  - **The Trigger:** Arduino outputs a 5V signal to the SSR input.
+  - **The Hold:** The internal zero-cross detector captures this signal. If the AC waveform is at a high voltage, the detector keeps the switch open.
+  - **The Cross:** The AC waveform drops to 0 volts.
+  - **The Action:** The detector immediately triggers the internal TRIAC, turning on the load smoothly with zero initial voltage.