What is the difference between leading-edge dimming and trailing-edge dimming?
Leading-Edge (Forward-Phase) vs Trailing-Edge (Reverse-Phase) Dimming: Technical Analysis
Phase-cut dimming technologies represent two primary approaches to lighting control with distinct technical characteristics. This comparison examines their key differences across multiple dimensions:
1. Switching Devices & Trigger Mechanisms
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Leading-Edge Dimming
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Utilizes silicon-controlled rectifiers (SCR)
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Delays trigger angle at AC waveform's rising edge (0° phase) to chop input voltage
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Experiences incomplete current interruption due to SCR's natural zero-crossing cutoff
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Trailing-Edge Dimming
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Employs MOSFET/IGBT transistors
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Conducts at zero-crossing with delayed turn-off for dimming
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Full control capability with no residual current issues
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Core Difference: Leading-edge delays turn-on, trailing-edge delays turn-off.
2. Waveform Control Principles
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Leading-Edge: Modifies waveform's front portion by delaying SCR trigger angle
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Trailing-Edge: Adjusts waveform's rear portion by delaying MOSFET turn-off
Key Point: Leading-edge chops the waveform's first half, trailing-edge modifies the second half.
3. Performance Comparison
|
Parameter |
Leading-Edge |
Trailing-Edge |
|---|---|---|
|
Dimmer Range |
Wider (0-100%) |
Limited (10-100%) |
|
Load Compatibility |
Best for resistive loads (incandescent/halogen) |
Optimized for capacitive loads (LED) |
|
Stability |
Prone to EMI/audible noise, residual light possible |
Low EMI, smooth dimming with no residual |
|
Cost/Installation |
Lower cost, compact size, compatible with existing wiring |
Higher cost, complex circuitry but simpler installation (single-wire method) |
|
Compatible Bulbs |
Incandescent bulbs, halogen bulbs, select LED bulbs |
LED bulbs, energy-saving bulbs |
4.BSEED Dimmer Switch Compatibility Guide
BSEED dimmers utilize leading-edge dimming technology, therefore:
Suitable for: Incandescent bulbs, halogen bulbs, and LED fixtures supporting leading-edge dimming
Not suitable for: LED or energy-saving lamps that only support trailing-edge dimming
Before purchasing and installing, please ensure your lighting fixtures support leading-edge dimming. Failure to do so may result in flickering, inability to dim, or damage to the fixtures.
Summary
When selecting a dimmer switch, the key lies in matching the lighting fixture's driver with the dimming method.
If you use traditional lighting fixtures or LED lights supporting leading-edge dimming, the BSEED leading-edge dimming switch is your ideal choice.
If you use high-end LED lights that only support trailing-edge dimming, you need to choose a corresponding trailing-edge dimmer.
👉 If you're looking for cutting-edge phase-tapping dimming switches, discover BSEED dimming switches to elevate your home lighting experience with enhanced comfort.
