Hi there,
I’m installing some ZBMINI-L2 (no neutral) switches to automate lighting on an old wired house.
I initially didn’t think much about it and just followed the wiring instructions, but quickly I discovered that when the switch is off, the lamps still stay a little bit ON.
After thinking about it for a bit I realize now this is becasue the device is actually taking the neutral / closing the circuit through the lamp, so there’s always a little bit of current going through the lamp even when the switch is turned off.
So here are my questions on this topic, after failing to find good information elsewhere:
Are there any specific type of led bulbs recommended for this use case that won’t emit light even if there is a small current going through them? Dimmerable vs. non-dimmerable? What’s the detail that would make this work properly?
I imagine it would be possible to alleviate the issue by installing some other load in parallel to the lamp, a sort of bypass. Is this thinking correct? and if so, what is the simplest appropriate component to install for this purpose, considering this is a 220v AC electrical installation?
Any guidance greatly appreciated.
Thanks,
Julian
I am a bit lost on the problem, so you are saying that, device is using line cable going through lamp as a replacement of neutral? I do not know how it would work, on the other hand, can you validate this via removing the lamp and checking if the device is still running? Because, taking what you are saying granted, it should always require a functional lamp, removing functional lamp should break the switch (operationally)
I am worried about the current on the rest of the circuit and could not find a disclaimer around it.
Please keep in mind:
The ZBMINI-L2 does not support dimmable LED light/bulb and inductive load such as fan etc.
The power of the light must be more than 3W.
Bypass capacitor is not needed.
I can confirm that if there is no lamp the device doesn’t work at all. That’s how it actually finally dawned on my how the device can possibly work without a neutral in the first place.
BTW, thanks everybody for the additional information. It helps confirm my suspicion of what is happening with this.
In the light fixtures where I have this problem, what I notice is “glowing”. The light fixture that I’m paying particular attention to has three led bulbs, non-dimmerable, and definitely higher than 3W. Still, when the switch is off, the residual wattange is sufficient to make them glow.
Any idea on what particular specification should I look into when trying to buy replacement light bulbs such that they won’t glow with this minimal wattage?
Try almost any other bulb. Sonoff does claim no bypass needed, but i’ve always doubted that claim, i think its just something almost safe enough to claim with most modern bulbs.
I had some old bulbs that would glow just from flow from another circuit in the same j box.
I use lutron caseta no neutral switches here in the US, not zigbee, but same basic trickle power scheme, and have only had an issue with older bulbs. Everything bought in the past few years of multiple brands has been OK.
Thanks a lot. I resolved the issue by replacing the bulbs for higher quality ones.
I got a set of Phillips brand bulbs and that took care of the stray current, all peachy now.
