The appartment I bought some years ago allready has a dimmer switch on the wall. Problem is the ceiling light use halogen. They don't sell the same halogen bulbs anymore so I removed it and bought a new cheap LED ceiling light, here's the specs:

  • 12W LED, 555 lm, 220V-240V (50 Hz)
  • T = 3000K, Ra >= 80

I tried to read the voltage from the wires in the roof, its 100V. Lights wont turn on. The voltage does not rise or drop after rotating dimmer switch.

And a manual I found online show only one type of dimmer switch for EGANT: U328. The one I have is B328. It says U328 only support old bulbs or halogen but not LED. U325 on page 39: https://manualzz.com/doc/30910711/lamp-plug-and-sockets U327 supports LED. I have no idea if it supports LED. I tried the light on 220V outlet and it works, but not on dimmer.

Is there a difference between EGANT B328 and U328? What could be wrong, could it be it does not support LED? so, if it doesnt support its obvious i should buy a new dimmer switch.

  • Most old dimmers do not support LED fixtures or bulbs because of the internal electronic circuitry. insights.regencylighting.com/…
    – Gil
    Commented Jul 30, 2021 at 21:31
  • Get the correct dimmer. I could not find the technical information on the dimmers you referenced.
    – Gil
    Commented Jul 30, 2021 at 21:43
  • I bought a new dimmer and problem fixed. Commented Aug 2, 2021 at 11:28

1 Answer 1


Most old dimmers do not support LED fixtures or bulbs because of the internal electronic circuitry. https://insights.regencylighting.com/heres-an-overview-of-common-led-dimming-issues-and-how-to-fix-them The old style dimmers were generally triacks but could also be SCRs. These devices need a current to turn on which by design was taken from the load. When the triack/SCRs turn on they and this voltage disappears until the cycle goes back to zero. The triac/SCR shorts the source turning on the light. This works great with bulbs however very poorly with LEDs as that small amount of current will cause them to illuminate. LEDs are current devices and bulbs are voltage devices. By reducing the power the older bulbs will dim, using a LED you wind up with a very narrow dimming range. The older dimmers would not turn the triac/SCR until a given delay has passed from zero cross. The longer the delay the dimmer the lamp. The Triac/SCR turns off at zero cross. LEDs are current devices and PWM works best for them. Simply stated the dimmable LED bulbs convert the variable power to a PWM signal.

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