Transformer Hum with GE Smart Switch

Devices & Integrations
21

The best thing may be just to get in touch with the fixture manufacturer and see what switches they recommend.

22

Apart from trying a warranty repair, you could try replacing the transformer. Or if you can open it, humming could be due to the core not being tight enough. Humming is usually mechanical due to vibration.

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23

Thanks everyone. I contacted the manufacturer this morning and they let me know I needed to use a compatible dimmer, and sent this model specifically:

Obviously, the issue is that it’s not a smart dimmer. Do you all know what I should look for in a similar smart dimmer to make it work? I tested this leviton dimmer out (from Home Depot) and still had the issue. Is it worthwhile to try and order the Lutron z-wave dimmer and see if it works? I guess part of my question is in trying to understand what would make a dimmer compatible with a light to begin with so I do a bit more intelligent research, rather than just buying a bunch of dimmers and hoping things work via trial and error.

I’m also noticing these Lutron dimmers are ridiculously expensive - even the “dumb” ones are $75 for the single pole, $113 for the 3-ways compatible ones.

Thanks!

24

Lutron is an engineering company that focuses on lighting. They hold a bunch of patents and can often do things that other companies cannot.

They do make smart switches which can integrate with SmartThings, but they don’t use zwave or zigbee. They use their own proprietary protocol called clear connect. So to get the SmartThings integration not only do you need their smart model switches, you have to also buy the Lutron SmartBridge device. I use their smart Caseta switches in my own home and like them very much, but I don’t think it would be worth it just for one switch.

25

Thanks @JDRoberts - I actually found a start pack for $79.99 on Amazon - it’s about $30 more than a switch. Given I’m past my return period with these pendant lights and they’re already installed, that actually doesn’t seem like too bad of a penalty for me to pay for not having done this research before. And I can always return it if it doesn’t work. Other than the added cost, are there are difficulties with trying to run the Lutron system in a house filled with z-wave switches?

Also, I’m new to this, so the idea of experimenting with a new system and having the capacity to add different types of switches is
fun. So, that benefit as well.

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26

Now as to why lights hum when you dim them


The short answer is physics. Or vibration. The process of dimming causes either a physical vibration, typically in metal plates that are part of the fixture, or an EM vibration. But the hum is basically a rattle. The thing is there are different parts that can vibrate and so the hum may be coming from different causes.

And this article describes how different types of bulbs/fixtures get vibration in different parts:

But before all that, a brief mention on why it can be just a matter of trial and error to fix. First of all, dimming isn’t what you think it is. It’s not usually just a matter of sending less current, like turning a knob to turn down the heat on a stove

Instead, dimming as done by most dimmer switches is a trick.

Dimmer switches work by chopping up the AC current flowing between the switch and the light. Rather than literally “dimming” the light itself, these switches actually cause the current to undulate or flicker extremely rapidly, so that to our human eyes, it appears that there is less light.

And if You really want the details on how that happens, see the following. It also explains the difference between different engineering approaches and why expensive dimmer switches might not have the hum. Read the article all the way to the end for discussion of the various design approaches and how different switches may differ.

And all of this has a specific implications for transformer cores, which is what @NomadTech was referencing. Read the following: it applies to transformers of any size, including the ones in your light fixture.

So you can see that sometimes it’s just a matter of swapping out the various pieces (Bulb, switch, fixture) until you find a combination that isn’t creating the hum.

And sometimes it’s a matter of literally swapping out pieces, if the transformer inside a particular fixture has gotten a little warped over time and has an unfixable hum.

That’s more than most people care to know, but if you’re really interested in the details, that should get you started. :wink:

I guess part of my question is in trying to understand what would make a dimmer compatible with a light to begin with


And this post is what happens when you ask an engineer to explain what’s causing the problem rather than just offer a solution. LOL! :rofl: ( but you did ask
)

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27

No operational issues. The switches operate on a different frequency and shouldn’t cause interference with the Z wave switches or vice a versa. :sunglasses:

The main issue with backbone planning is that the Lutron devices are essentially their own mini network, so they will not act as repeaters for any of your other devices. That’s not a problem in and of itself, it’s just that a lot of people rely on their smart switches to be the repeaters for their Z wave network. So if you are using lights switches of a different protocol then you have to start thinking about what zwave repeaters you will have available. ( most commonly plug-in pocket sockets.) :sunglasses:

28

Got it. It’s in the kitchen so the repeater functionality would be redundant as I have multiple z-wave switches within several feet.

I guess I’ll give it a shot. Really appreciate your help @JDRoberts

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29

Well, that may not work. Apparently that Caseta dimmer isn’t an “ELV” (electronic low voltage). Are any of the smart dimmers out there ELV vs line?

30

See posts four through six above.

31

Thanks - Sorry, I think I was confused as the Eaton & Cooper brands appear to be the same. I just ordered this one as it seems rated for ELV. Not z-wave plus, but hopefully will work.

32

Eaton is the company, Cooper is the division, and aspire is the model line.

You may find the same device listed under any combination of those three names. :sunglasses:

Many of Leviton’s zwave models are universal dimmers as well, Including their Z wave plus models.

33

Thanks - Tried leviton and it didn’t work, so will cross fingers with the Cooper/Eaton/Aspire

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34

If that doesn’t work, there is an ELV dimmer in the Lutron Caseta line, it’s just very expensive. Really slick device, though, there are a lot of parameter settings you can change to try different options for different loads. :sunglasses: You would still need the SmartBridge device as well for the SmartThings integration.

https://www.amazon.com/Lutron-Wireless-Lighting-PD-5NE-BL-Assistant/dp/B01M22SK1W

The Caseta elv+ dimmer is a great solution for LED fixtures with integrated, built-in drivers, elv track lights, and problem leds that may prefer an elv dimmer.

Read the Amazon comments, there are a couple of tricks to working with it.

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35

Yeah I saw that. It ran $100, maybe $113 for the dimmer, and no available starter pack so would set my back $200 just to get this one switch. But still an option if the Cooper doesn’t work

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36

Quite a few community members buy Lutron devices from energy Avenue. I haven’t used them, but community reports are good, and they are usually the lowest cost on Lutron:

https://www.energyavenue.com/Lutron/PD-5NE-WH

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37

If you would like to invest in the Lutron Caseta product line, I would recommend you look at pricing on EnergyAvenue.com. They have some of the best online pricing I have found. For example, the PD-5NE-WH dimmer is listed at $87, instead of $99 like everywhere else. They also have the new Caseta Fan controller for $50 instead of $60 everywhere else.

EDIT: Looks like @JDRoberts beat me to the Energy Avenue tip! :wink:

One more tip, I would recommend buying the Lutron Caseta SmartBridge Pro2 (available for $88 on EnergyAvenue.) The “Pro” version of their bridge includes the ability to use Telnet for integration with systems like Hubitat. This provides a means for a 100% local communications protocol without any need for a cloud server. While the “Pro” version is not needed for SmartThings (as ST uses a cloud to cloud integration for Lutron), it might be worth considering to future-proof your investment should you ever decide to try a different home automation platform.

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38

Thanks everyone! Yes, that definitely looks a bit cheaper.

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39

Just occurred to me that you could yank out that transformer and use a smart dimming switch.

40

Wow, that’s interesting. Do you think that would work? I guess I don’t know enough about electrical - it doesn’t need the transformer? They are flat disc LED pendants - not bulbs.