Start a new topic

Sonoff devices used with dimmers – a fix?

I have dimmable LEDs installed in down lighters. Some are connected through wall switches, which I guess are simple attenuators since there is only a live wire. Others are connected through RF relays. I have the same issue in both situations.


The “dimmers” reduce the voltage supplied to the Sonoff devices (and the LEDs), but the Sonoff will operate down to 90VAC (in reality, I have measured down to 50VAC), but the RF relays still need 220V, so I have to connect the Sonoff after the relay or wall switch and leave the relay / wall switch turned ON.


Problem: When I trigger the Sonoff device, even when the “dimmer” is turned on to maximum, the Sonoff device will activate and immediately reset. This is not 100%, maybe 40% of the time. With the RF relays, it also resets the RF relay, but the RF relay can’t be the cause if this phenomenon because it also occurs with wall switches.


Several years ago, I heard of a fix for a problem with LED bulbs where they continue to glow even when the wall switch is OFF. The fix is to connect a 0.1uF, 250V capacitor between live and neutral. I had several capacitors left over, so I tried a capacitor, and IT WORKED.


With a capacitor connected across the live / neutral input to the Sonoff device, it would work 100% of the time


Questions to electrical experts out there:

- Is this safe? (it’s a capacitor, so essentially open-circuit and only removing voltage spikes and surges?)

- With the RF relays (Chacon DiO 54524), the capacitor is connected to the output, but it stops the RF relay from resetting – any thoughts? Originally I thought the problem was caused by the RF relay reset (which cuts power to the Sonoff), but that can’t be the source of the problem because I have the same issue through a wall switch


Good luck with this question, and I hope it gives someone a solution to their issue.

Login or Signup to post a comment