Installed Shelly Dimmer, strange behaviour with switch

Sooooo did the firmware update as soon as it came online.
And I turn it on and off in the app and in Hass, via a custom component.
But when I use the light switch nothing happens unless it’s already on and then if I quickly flick the light switch on and off it turns the light off.

It’s wired just like the included picture, very strange, should have tested on the out the box firmware first tho.

Anyone for any ideas?

It is made to be used with momentary switches of the box and to get the most function from it but if you use it with a standard toggle wall switch you need to change the button setting to toggle or edge switch. But you will only be able to control the dimming from the app.

I did change the switch type to all the different options and it didn’t seem to do anything.

I then took it back out the wallbox and started testing it on the kitchen work top, and it worked fine.
I’m gonna test it again tonight and install it again to see if it was just a random not taking the config change kinda thing…

Also I had to solder a couple of my boards where the screw terminals attach tio the pcb they didn’t get soldered that well and have been coming lose.

That might be it, all nicely laided out on the bench it worked, so the stress of a confined space with bent wires could be the issue.

Hi James, did you get this working? And how did you wire it into the switch? Mine have just landed and I’m not sure how to wire them in?

Sorry didn’t get round to it in the end, hopefully tomorrow after I’ve finished fighting with the pidgin on my balcony !

Good luck with the fight, do you have a picture of how you wired them in?

Hi James, I’ve just found this on is this how you’ve wired yours?

Yes, that’s it. I followed the image they had on the instructions.

I’ve installed two tonight, one works and the second doesn’t, I think that the second light isn’t dimmable (I thought all led lights were dimmable). Both keep flickering so I need to fix that.

Yea my bulbs aren’t dimmable yet. I’ll try having a look at the board, see if it need some more solder as it works fine wired up on the kitchen side.

Think I killed the board, miss wired it and popped the fuse board, corrected the misswire, now the Shelly can turn the lights on, but not off…

Have you tried updating the shelly, I had a few different issues and they all fixed on the update. Also, if you go to the shelly website they have a messenger bot, they always seem to reply to that.

Yea, think by miss wiring it I’ve killed it. They have responded, but it’s gone silent after 2 emails.

Once it on it can fad down, and up but off just has the bulb at max brightness. It’s like the transistor that turns it off is leaking.

Got a new one and again it works fine on the bench, but when I wire it up it behaves as before. Fine in the app (tho I have dimmable bulbs it doesn’t dim) and if I quickly turn the switch on and off it turns the lights off, if on, but never turns them on.

It’s madness as if I wire it on the bench it works fine.

Anyone have any other ideas ? I’ve tried changing the switch type to any others and rebooting and testing, but no luck.

If there a debug mode? Or rogue voltage on the switch pin, I’m lost and about to give up on dimming my bathroom light with this.

Obviously, the dimmer is working fine, and there is something different between the setup on your benchtop vs installed position. It is likely to be 1) difference in line voltage, 2) difference in switch voltage, or 3) difference in the load. It makes sense to prove and then eliminate those differences… can’t be hiding in a magic tree, so a DMM should be enough to determine the problem.

Earlier you said your bulbs aren’t dimmable above, correct? That would be difference #3. My shelly dimmers puke when non-dimmable led bulbs are installed (the flicker and behave generally weird). If it works on the bench, make sure that same bulb is used in the install location.

Difference 1, may be possible if you’re hacking it into a 3-way switch system. Unfortunately, shelly dimmers require a hot line, which makes them not suitable for a lot of different 3/4-way wiring setups. In fact, rarely do you see 3-4way with the line and load in the same j-box (and even more rare an electrician runs an extra wire for shelly compatibility).

Difference 2, again might be the 3-way wiring problem like #1. Also, shelly dimmers do require 120vac on the switch inputs, unlike other shelly devices that can use a ‘dead switch’ (those measure continuity instead of current).

All of these possibilites should be easy to determine using a good DMM. Beware of parasitic voltages when you are using cheaper DMM’s to measure volts on house wiring. This can lead to your DMM displaying 120VAC, even though it is really 0VAC (induced voltage, due to nearby current carrying wires… not only fools you into thinking the breaker isn’t shutting off, it also provides no current for shelly to read). To see through these ‘ghost voltages’, you need an impedance to load the line down (like Flukes with a Lo-Z feature). Regardless what you use to test, please be careful near mains lines!

On an unrelated side-note: the above posted image shows technically correct wiring with respect to physics, but really the line wirenut should have 2 pigtails, one for the switch and one for the dimmer. Wiring the dimmer to the switch like that isn’t as efficient, and in some places that won’t pass building inspection. Even if you aren’t getting inspected… 9/10 times this kind of cheap/lazy wiring job (especially when it is done like that at every outlet) is why that nice air compressor keeps tripping the fuse breaker on a cold start, and the lights dim when the wife is drying her hair. :wink:

[edit: I should add that at first I had the shelly app configured to “edge switch”, which allows ‘standard wall switches’ to be used as normal. If you are using one of the other modes for momentary switches, your standard wall switches will behave weird (I’m guessing you already know this). Since then, I have my dimmer switches configured as “detatched”, and configured the “url when on/off” actions to hit a nodered http endpoint. That brings the switch position in to HA, so it can acted upon by automations. This offers more flexibility and reliability with automations, because you don’t have to worry what the shelly might be doing on it’s own.]

My hats off to you ! That is an amazing post and my quick skim read of it doesn’t do it justice.

When I don’t have my 3 year old on my hip I will try to give it good read.

Thank you for taking the time to write a really detailed response to what must have came across and a ranty post.

LOL, yeah just a tid bit tldr sorry… got bored and the result was a shotgun post. :wink:

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I just got two of these and am still trying to figure out the wiring. I’ve got a set of 4 LED downlights that are dimmable but they are only on a simple on/off switch.
I like the Shelly night mode feature though so I’m wondering two things

  1. Can I connect these to a simple switch like this and only use 5e app to dim. The switch should just work for on/off

  2. I’ve got two more sets of LED Dow lights but these are connected to a simple dumb dimmer knob. Can I put the Shelly behind this dimmable knob to give smart dimming control goes the system or will it get confused with essentially double dimming…

Now if I could only figure out the wiring I’d be golden. Got a shelly1 working really well in one set but can’t figure out how to wire up the dimmer to that set