Suggestions needed to work around dumb ceiling fan wiring in a safe way

Just be aware that not all Smart “Switches” still use a real mechanical relay. Those that do not, often are not suitable for use with an inductive motor load. Tagging @Eric_Inovelli so he can chime in to be sure you purchase the appropriate device.

Here is the warning straight from the Inovelli Red Switch documentation.

Thanks for adding that info and tagging Eric, @ogiewon. :slight_smile:

I thought that since I'm turning the switch relay off in the switch settings, and using the switch like a button device to trigger Bond actions to turn lights or fan on/off, that the switch would not be put under any load related to the fan motor.

So you're saying that if the switch does not use a mechanical relay, that even if I turn the relay off in the switch settings and am not controlling the fan directly from the switch, the load still hits the switch?

Yes, I believe so. The smart switch's internal solid state on/off 'switch' will be what is passing power from line to load. The ability to keep it always on is a software setting.

I am sure @Eric_Inovelli will be better able to answer definitively if Inovelli has a suitable solution. Of course, the LZW36 Fan/Light controller is the exact product that Inovelli designed and engineered for this exact application.

@agnes.zooz from Zooz may be able to recommend a Zooz device that is rated to handle an inductive motor load, while still having the ability to keep the output always on, to allow the rocker switch to basically act as a 'button controller' (just like a Pico.)

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The Zen26 is also not rated for fans.

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Yes by putting the switch into smart bulb mode it basically means that it is making the internal connection from the hot line in to the load terminal - so the switch is on all the time regardless of button presses.

Motor loads like a pump or a compressor can pull three times the rated current on startup. A ceiling fan does not fall into this category. Yeah it will have a slightly higher startup current but not anything that will take out the switch.

Also damage can occur when switching off a motor. In this case you will not be switching it off so I don’t see an issue. But it’s a good note to make.

Also on another thread somewhere I read that a guy was using some brand of switch that I never heard of and when he connected his fan as described and pulled the chain, he was unable to get different speeds. Something in the internal FET circuit must have been limiting the current to the fan.

Edit: btw I do agree that bypassing the switch is the best thing to do.

Back to your other question. I have never used the ABC but yeah, I’m using the built in one.

There's no reason for not getting your Lifx to work.

You know, all you people w/your facts and knowledge and experiences are really making my life difficult. :wink:

OK...I'll await Eric and Agnes chiming in, would really like to hear their points of view on this.

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I do have one question about this general issue of fans and switches...we have had three fans wired up to a standard dumb switch for about 15 years. Same as the one in our living room that we've been talking about. Switches control all power to the fans via simple on/off.

Why has the fan engine load not been an issue in that configuration? Are standard dumb switches just all rated for fixtures up to and including fans?

Yes. A standard 'dumb' switch is literally two pieces of metal that are either separated (off) or forced together (on). There are no sensitive electronics inside, and they are rated to handle quite a bit of electrical current. In the USA, a typical dumb wall switch can handle 15A at 120vac, or roughly 1,800 Watts.

Inductive loads, like electrical motors used in fans, pumps, compressors, etc..., can have huge in-rush current requirements when turned on, and can generate significant 'back-emf' which can damage devices not designed to handle it.

In short, if you want to be safe, always use devices designed for the specific electrical load. And do not use devices in applications that they are not designed for.

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I’m not arguing with you and I agree.

Just to put this in context though, a typical ceiling fan on high pulls approx half an amp. But this is the current in the main winding. The startup winding is smaller on these low torque motors and - just throwing out a number because I have never actually measured it - might draw another half amp inrush. I could be wrong. IMO this isn’t going to pop anything that is rated for a 5A resistive load.

But as said, I am not going to recommend going against any documented recommendations from the switch vendors.

I once had a conversation with @agnes.zooz about using a zen21 for a bathroom exhaust fan and she recommended against it. I told her I understood but would take my chances. Later they revamped their recommended usage to include exhaust fans.

I really hate it when it's one of those "It should/might work, but it also might not" situations. :wink:

It's looking like the Inovelli fan switch may be the best option to avoid potential issues. I'd hook it up in the box that is sending power to the fan, and wire up the Inovelli receiver in the fan canopy, I assume that replaces the existing receiver, which would mean the original remote that came w/the fan would no longer function.

AFAIK the Inovelli will work w/a dumb switch as the secondary switch in a 3-Way. However, I'm not sure what happens when using the dumb secondary switch after installing the Inovelli fan switch...does it turn everything off, or can you program the Inovelli switch to control what the dumb secondary switch turns on/off?

A motor looks like a dead short when they are sitting still. They will have enormous current flow when they are not turning.

This was the biggest issue I had, and I killed a couple switches because of it. The motor acts like a generator when it is turned off, yet still spinning. That spike of electricity literally zaps electronic devices to death.

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Nope it will not. The 3way (or 4way) switches will have to be smart switches that then accomplish their function through scenes setup on hubitat or zwave associations. With zwave associations you may be somewhat limited.

Thanks. I just went to look at the switch docs, and it says the Fan Switch will not work in a 3-way setup at all...so that seems to end that option. This is making me nuts...


image

Their red series switch works in 3-Way w/dumb and smart switches, but I guess not the fan switch.
https://www.amazon.com/Inovelli-SmartThings-Technology-Indicator-SmartStart/dp/B07T2416D8/ref=sr_1_2?dchild=1&keywords=inovelli+red&sr=8-2
image

So I guess I could install the Inovelli Fan switch in the main switch box that is sending power to the fan, but not hook it up as a 3-Way. Then remove the add-on switch in the other box, tie-off the wires there appropriately, and replace that second switch with a Pico programmed to run the fan. So I'd end up with the Inovelli fan control in one spot, and a Pico in the other. That should work, right?

Yes! This is exactly what I would do.

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There are many ways to accomplish a three way setup when using 2 (or more) zwave switches. You can not WIRE UP the inovelli fan switch in a 3 way configuration, but you can certainly have other dedicated switches that control the fan and light. That is kind of the basis of what a home automation hub does. So although it is not hard-wired as a 3-way, the hub or zwave association allows it to work in exactly the same way.

I am happy with the hub controlling the 3 way aspects, although there is a slight (well under a second) delay. If you want virtually instantaneous reaction you can use zwave association that doesn't go through the hub. You need the hub to set up the initial association, but once its setup the association will work even if the hub is removed from your home. In my house, I have a few of these, they are fast. So fast, that in a blind test with a number of my friends they were unable to tell which switch is hooked up to the light and which one is associated.

This would work as well, kind of the same thing as mentioned above:

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Again not disagreeing.

Well I disagree about the dead short part because any winding has DC resistance component.

But can you put this in context? Are you talking about ceiling fans or some other type of pump, motor, or compressor?

OK...I think that's the plan until it isn't the plan. :wink:

Pic of what I understand is the add-on switch in the curren three-way setup, the one I'd tie off the wires and replace switch w/a Pico.

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My house has switch loops almost everywhere. What I did in my master where the fan w/lights are remote controlled was to wire the fan w/light directly and then rewire the switch loop so it was no longer a switch loop. It’s now just a hot neutral and ground which I used to power a Zooz Zen 26. The Zooz is set up to control some of the bedroom lights or all of them depending on how many times you press the top switch.