Thyristor dimming (TRIAC dimming) is a technology left over from the traditional incandescent lamp era. Although it has strong compatibility, it has obvious defects in the LED era. The following are its main disadvantages and reasons:
1. Compatibility issues
A specific driver chip is required: ordinary LED lamps are incompatible with thyristor dimmers. Forcing them to match will cause flickering, inability to dim, or damage to the circuit.
Dimmer matching is complex: the performance of thyristor dimmers of different brands varies greatly, and "TRIAC dimmable LED lamps" must be selected, which has a high trial and error cost for users.
2. Poor dimming effect
Flickering at low brightness ( when dim to 20-30% will flicker ): When the brightness is adjusted to low, due to insufficient maintenance current (the current required by LED is much smaller than that of incandescent lamps), the lamp beads may switch on and off frequently, resulting in visible flicker.
Nonlinear brightness change: The dimming curve is not smooth, and there may be a sudden "jumping feeling" of brightening/darkening.
3. Energy efficiency and loss
Energy waste: Thyristors dim by cutting off the AC waveform, and the unused electrical energy is converted into heat, which is less efficient than PWM or digital dimming.
Shorten LED life: Current instability and heat accumulation will accelerate LED light decay, especially low-end drive power supply is more susceptible to damage.
4. Other issues
Noise interference: Poor quality thyristor dimmers may generate high-frequency noise (such as inductor hum).
Electromagnetic interference (EMI): Waveform cutting may interfere with other sensitive electrical appliances (such as audio, radio).
Applicable scenario suggestions
Choose thyristor dimming carefully: only suitable for situations where traditional dimming switches are installed and the lines are unwilling to be modified (such as replacing old spotlights).
Preferred alternatives:
PWM dimming: suitable for scenes with high requirements for smooth dimming, such as table lamps and display backlights.
Smart dimming: such as Wi-Fi/Zigbee dimming , supports stepless dimming and can be remotely controlled.
User response plan
Replace the dimming system: completely switch to digital dimming (such as DALI) or smart lamps.
Choose high-quality compatible lamps: Look for "TRIAC dimmable" models marked by the brand (such as some products of Philips and Osram, BENWEI).
Install a decoder: Install a TRIAC-LED decoding module in front of the lamp to improve compatibility (higher cost).
Thyristor dimming is an outdated technology in the LED era. Unless there are budget or conditions, it is recommended to upgrade to a more advanced dimming solution, you can consult DALI dimmable and 0-10V dimmable on http://www.benweilight.com
