Improve Zwave coverage: is a micro better than an outlet?

Wanting to improve my zwave coverage upstairs and wondered if a zwave plus relay micro switch that was wired in with my AC powered smoke detectors would provide better coverage than say an outlet. All of my smart switches are wifi but im doing zwave for fan control because for some reason wifi fan controls arent being made. So whatcha all think? There is plenty of space in the ceiling above the smoke detector. Think it might be better than an outlet?

All mains-powered device classes should be pretty much the same with regard to acting as repeaters. So it all comes down to barriers and location for any given repeating device.

For example, because the micro is buried inside the ceiling, you would expect some reduction in range. How much depends on the materials surrounding it. If you have ceiling tiles below or some types of carpet insulation above, that could block some signal.

The best in terms of range is an open air device, like a plug-in pocket socket. But then if it’s behind a large appliance like a refrigerator, that will block its signal.

Sometimes the best repeater is a lightbulb. Not much to block it, as long as the fixture itself isn’t too ornate.

There are a number of possible issues with using zigbee bulbs as repeaters, but most of the zwave bulbs make very good repeaters and can sometimes be placed in a location, like a stairwell, where there really aren’t any other options.

Zwave products .com has a sale on right now for the indoor floodlights where you can get one bulb and an onwall battery-operated switch for it for $19, which is a really good deal. :sunglasses::level_slider::bulb:

https://www.zwaveproducts.com/shop/z-wave-lighting/z-wave-light-bulbs/gc-light-kit-gocontrol-lighting-kit-with-scene-controller-and-br30-dimmable-led-indoor-flood-bulb

But normally you can get an RGBW color zwave bulb for around $29. Linear, GoControl, Hank, Domitech, Homeseer, Aeotec, GE Enbrighten, and Leedarson, are all good brands. Just remember Z wave repeats only for Z wave and Zigbee repeats only for zigbee, so make sure you get the right protocol.

Oh, and zwave plus will have significantly better range than Classic zwave regardless of the device class or brand.

I thought about the bulbs but dont have to be on to repeat? If lights are off no repeat correct?

Im thinking the smoke detector with a micro is no worse off than an outlet at this point. Figure the outlet is boxed in a plastic box shoved with wires and surrounded by drywall.

I see these micro relays have little antennas so im hoping that may help as well. Wonder if there was a way to extend the antenna through the attic! In any case think im gonna try one. I really dont want an open air device plugged into an outlet if i can avoid it. Wonder if anyone has every tried this as a mesh tool. Thanks for your reply.

Definitely people use micros as a mesh tool, most people in the EU are using micros rather than all in one light switches, so the micros may be their primary repeaters. They work fine, they just don’t work better than the other device classes.

As far as the lightbulbs, they have to be on current but they don’t have to be showing any light. When you turn off the smart bulb with a network command, it goes to 0% brightness but it still has current available to it so it can hear the next “on“ command.

The deal that I linked to has a battery operated switch that fits over the existing light switch. So you leave the existing light switch in the on position but now you have two buttons in that same place to press for on and off of the bulb without actually cutting the current to it. :sunglasses:

Now for the antenna question. For most people, this will be obscure, overly technical, confusing, and hard to understand. :scream:

For those with a background in network engineering, it boils down to one word: resonance. (Yes, I know that’s not helpful. :wink: )

So let’s jump to the conclusion and try to make it as simple as possible: with antennas, the length is very important to the performance of the device. You can’t just add more and more antenna and make it work better, or at all. It’s a very specific length. Remember that these devices transmit as well as receive. That becomes very important.

The best “match” ( that’s a technical term in this context) works out to the same length in centimeters as the wavelength. That has to do with the speed of light through air. But you can also get pretty good results at either half length or quarter length, as long as you are precise about it and also take some other factors into account. That all has to do with resonance.

It’s likely that the antenna in a home automation device is a quarter length antenna. It’s also likely that most of its length is soldered onto the internal circuit board, which is also holding it in a precise position.

So… Is it possible to extend the zwave antenna? Yes, but only up to a maximum length of about 4 inches, you have to be very precise about the length, and you have to exactly match the other characteristics of the existing antenna.

And if you can see a separate antenna sticking out of the Z wave device, it’s probably already been extended to maximum length.

( and remember, this is the short simple answer! )

For the full explanation, see the following:

https://www.digikey.com/en/articles/techzone/2017/apr/understanding-antenna-specifications-and-operation

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Thanks for the info. Interesting about the bulbs. I would have to do the switch thing you mentioned to keep it powered to keep the zwave repeating.
Im gonna try out a couple of the enerwave micros in my smoke detectors.

Im still perplexed why my ST V3 hub cant connect to my Ge fan control that is zwave plus and its one room away. House built in 2002.

You might need to do a general exclusion if it is failing to pair.

Yeah did the exclusion and repair and still no joy. Its my only zwave device. It sucks that once you start on ethernet there is no way to swap over to wifi for the ST hub. That way i could move the hub to the room and just see if it will pair there and then move it around the house till it drops then i would roughly know where to put a other zwave device. Hope they can fix this soon so i can move my hub around without having to reset the whole thing as i have a bunch of wifi devices on it.

There is, it’s just not obvious. See the following:

Remember, though, that every time you physically move the hub around your Z wave devices get confused about who their neighbors are. So you need to run The zwave repair utility once you have the hub back in its original location

There’s probably a simple answer to this, but why don’t all repeating devices that hear a signal repeat it once until it gets to the hub, then repeat the answer from the hub once back to the device?
Wouldn’t this prevent errors from moving your hub or devices and increase communication since everyone’s working together? Maybe slap a little metadata on the signal so the hub knows that it can ignore all the signals except the first one it gets?
This is the picture I had in my head when I first heard “mesh network”.

The simplest answer is that you would massively increase the amount of traffic on the total network. And massively reduce the resources available to handle that traffic. Remember that Z wave and zigbee devices are designed for little tiny messages transmitted infrequently. If every device that hears a message transmits it every time The whole mesh concepts falls apart.

Plus, then the battery operated device is going to receive multiple copies of everything and have to respond multiple times and use up its battery multiple times more quickly.

Imagine a pony express station with four horses. A message comes in. We give a copy to each of the four riders, Send them all out to the same destination, have the person at the Destiination handwrite 4 copies of the answer, and have each of the riders bring back a copy of the reply. Suddenly our very efficient system is very inefficient. And our horses are very tired!

Also notice that in this scenario adding more horses makes the system more inefficient, because they’re still all going to the same place and that poor recipient is still going to have to make one copy of the message for each of the riders to take back.

In a normal mesh situation, adding more repeaters makes the network more efficient because there are more possible empty pathways available for each new message.

Sure, in a war situation you might send out some duplicate copies to ensure a message gets through, but for everyday work, our regular pony express system is going to be less expensive to run and more efficient to operate.

:sunglasses::horse::horse::horse::horse:

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But if a horse does get lost along the way…

If the Station doesn’t get a response in the expected period Of time, they will send out a second horse. Still way more efficient than sending out every horse every time to the same recipient. :sunglasses:

JD- I’m curious to know if the switches you got in this package work well for your ST setup. They’re $15 now and I need some new wall-mount switches since the Sylvania Dimmer switch I acquired for $12 doesn’t seem to be selling at that price any longer. So- specifically- did you have any issues pairing the switches?

I only have one of those, but it’s worked well for me, remember that that’s a battery operated device, so it won’t act as a repeater, the repeater in the kit that I referenced was the bulb. :sunglasses:

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