Multi-Channel AC Dimmer Control: 2CH and 4CH Guide Feb 26, 2026 0 462 TL;DR: 2CH 8A and 4CH 10A modules share one ZC pin across all channels. Each channel has its own DIM pin. One interrupt call in code covers all channels; brightness is set independently per channel ha... ac-dimmer Arduino ESP32 ESP8266 multi-channel RBDdimmer tutorial Read more
Which AC Dimmer Module to Choose: Complete Buyer's Guide Feb 26, 2026 0 621 TL;DR: Three questions determine your choice: (1) load type — resistive (heater, incandescent) or inductive (motor); (2) load power in watts → calculate amps → pick a rating with a ×1.3 safety margin;... ac-dimmer Arduino buyer-guide dimmerlink ESP32 TRIAC tutorial Read more
Zero-Cross Not Detected: AC Dimmer Doesn't Respond to Commands Feb 26, 2026 0 513 TL;DR: An AC dimmer can't regulate the load if the microcontroller isn't receiving the zero-cross signal (the sine wave crossing zero). Without this signal it's impossible to calculate the TRIAC firin... ac-dimmer Arduino ESP32 troubleshooting zero-cross Read more
Wrong Library: RBDdimmer Instead of rbdimmerESP32 on ESP32 Feb 26, 2026 0 425 TL;DR: For ESP32 you need rbdimmerESP32 — not the old RBDdimmer . The old library was written for Arduino AVR: no IRAM_ATTR , no core pinning, no race condition protection. On ESP32 it causes Guru Med... ac-dimmer Arduino ESP32 troubleshooting Read more
TRIAC Overheating: AC Dimmer Runs Hot or Burns Out Feb 26, 2026 0 385 TL;DR: A TRIAC is an active device with a voltage drop of ~1.2V. At load currents above 2A it dissipates several watts as heat. Without thermal management: overheating, thermal protection triggering, ... ac-dimmer Arduino TRIAC troubleshooting Read more
AC TRIAC Dimmer Is Not PWM: How Phase-Cut Dimming Works Feb 26, 2026 0 479 TL;DR: analogWrite() and PWM don't work with an AC TRIAC dimmer. A TRIAC is not a resistor or a DC transistor. It regulates power using phase-cut control : it opens at a precisely calculated moment ea... ac-dimmer Arduino ESP32 TRIAC troubleshooting Read more
LED Lamps with AC Dimmer: TRIAC or MOSFET — Compatibility Guide Feb 26, 2026 0 550 Short answer: There are two types of AC dimmers: TRIAC (leading edge — for incandescent bulbs, halogen, heaters) and MOSFET AC dimmer (trailing edge — purpose-built for LED lamps). If an LED lamp flic... ac-dimmer Arduino LED MOSFET trailing-edge TRIAC tutorial Read more
Trailing Edge vs Leading Edge: Which Dimmer Method to Choose Feb 26, 2026 0 658 Short answer: Leading edge is the standard TRIAC dimmer — it opens the load in the second half of each AC half-cycle (best for incandescent bulbs and heaters). Trailing edge is a MOSFET dimmer — it op... ac-dimmer Arduino leading-edge LED MOSFET trailing-edge TRIAC tutorial Read more
LED Flickering with AC Dimmer: TRIAC or MOSFET — Causes and Fixes Feb 26, 2026 0 533 Short answer: LED flickering with an AC dimmer has three distinct root causes. Types 1 and 2 are caused by TRIAC architectural incompatibility with LED lamps — the hardware fix is a MOSFET AC dimmer (... ac-dimmer Arduino ESP32 flicker LED MOSFET TRIAC tutorial Read more