I’d like to be be able to control battery powered devices with a battery powered ZigBee device. For example, battery powered Christmas decorations controlled via ZigBee where routing mains power is not feasible. I don’t want the ZigBee device to power the battery powered devices, merely to operate a switch to close their own open battery powered circuit.
Anything that fits this bill. I appreciate some low voltage wiring would be needed.
No relays that I know of, most of the time a device that can be turned on and off from the network would use up too much battery power just listening for the next network command to meet mass-market requirements.
One possibility might be a switchbot button pusher. This uses Bluetooth to their own mini hub and then has an integration for smartthings. They work quite well. So as long as your battery powered decoration, either has a button or can be rigged with one, that might be an option.
There are also a couple of light switch covers, one Zigbee, and one zwave, that will physically move the switch underneath. So you would have to add a regular toggle light switch to the battery power decoration and then you could use one of those. If you’re interested in that, let us know, and I’ll post the links for the devices.
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Thanks.
I was aware of switchbot but I don’t want another hub or the clunkiness of it.
I guess there’s no option , I get the point about battery life a having to be in listen mode which possibly makes it not a feasible option.
You can add me to the potential customers who could use something like this.
In a sense they already exist since every battery powered ZWave/Zigbee thermostat can do exactly this. They power/trigger a 12-24VAC relay based on either a temperature event or a ZWave/Zigbee Trigger. And they last at least a year on 4 AA batteries.
IKEA blinds also do this and will drive a ~7.5V/ 1A motor and will turn that motor on and off for a couple of years.
So in theory this is easy. In practice they don’t exist.
I have considered buying a broken IKEA blind or an old Zwave Thermostat and see if I can it apart make something… But it is a shame that no one has offered something like this. Endless uses, (toys, Christmas decorations, low voltage lighting, wireless speakers, etc)
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Just spotted this.
Not sure but I think this might fit the bill if it can be powered by battery for long enough?
MHCOZY 1 Channel 5V 12V ZigBee Smart Relay Switch,Adjustable Selflock and Momentary Working Mode,Works with SmartThings, Alexa, Google Home (ZigBee Hub Required) https://amzn.eu/d/721IcqE
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It’s low voltage, but it’s not designed for battery power. Most people are using it for 12 V wired inline. It does have the option of 5 V DC power but because it’s not designed for battery power, it doesn’t operate in sleepy mode, which means it’s going to go through batteries really fast. 
Devices designed to run on battery power in a mesh network environment put a lot of engineering into power management. They will even identify themselves to the hub as battery powered, which will cause the hub to reduce the number of messages they receive, all to make the batteries last longer.
When you wire a device intended for mains power to a battery, you don’t get any of the power saving features of a device designed for battery operation, and battery life tends to be unacceptable for most people. You can try it and see if it works for you, but just set your expectations appropriately.
If their marketing numbers are right, it draws 0.08 Amps while it is doing nothing. By my calculation that means that it will kill a pair of AA batters in about 12-18 hrs.
That gizmo looks like it needs a transformer to work
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Yeah, I think part of the consumption drain is due to the fact that it’s maybe a repeater
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Has anyone tried running a zigbee 1ch switch, by powering it throb a solar power pack. This would supply 5vdc to keep the zigbee switch running… NZ$ 29.67 60%OFF | 80000mAh wireless solar power bank sos portable travel solar panel automatically recharges in the sun, external battery charger
https://a.aliexpress.com/_mNtQorg
Most Zigbee relays don’t run on that low voltage. But if you can find one, and it takes DC power, then, sure, running on solar is no different than running on mains. It’s just a question of how long the solar battery lasts. And, of course, cost: that’s a more expensive solution than most people are probably looking for.
I run my whole house on solar, the devices don’t know the difference. 
Some (perhaps lots) of the stuff on aliexpress have vastly overstated features.
I would be a little sceptical of this really being 80,000 Mah capacity.
I have a couple of 10,000 mah power banks that are broadly that size, hard to see that this could be 8 times the capacity and incorporate solar a charger without being very significantly bigger?
I’ve seen one about that size from Muyey, but it’s not a quick charger, so figure about 4 hours of battery life and then a 20 hour recharge cycle. Which since it’s solar might mean 3 or 4 days until you can use it again.
Those kind of devices are normally intended just for emergency use.
I don’t really think it’s feasible that a device that size has 80,000 mah capacity.
See this video from big Clive (worth a follow on YouTube)
Where he tests a unit of similar dimensions that’s claimed to be 100,000 mah and it’s actually 5200 mah.
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Yeah, I understand the comment, but the answer is that it’s not easy in theory, which is why you don’t see it much in practice. There’s more going on behind the scenes than is obvious.
Battery powered locks, thermostats, and sprinklers are different from switches and relays in a couple of ways.
First, they’re typically much bigger boxes. Most battery powered locks and thermostats use at least four AA batteries, and some use six. Relays of that size would start to look like a brick, and won’t fit a lot of the typical use cases.
Second, and this is where the “it’s not easy“ part comes in, is that devices of this type work differently than sensors when it comes to picking up their network messages. Most of them use a technology similar to Z wave’s FLIRS. They do wake up every second or so, but all they do is check to see if a nearby Mains powered device, which is acting as their answering service, is holding any messages for them. If it is, they wake up fully, and process that message. If not, they go back to sleep. It’s the equivalent of a person sleeping in bed who wakes up just enough to open one eye and check the alarm clock, and then goes back to sleep without ever fully waking up. This extends battery life significantly.
There is a similar technology available for Zigbee, although it’s a bit trickier to set up. The “repeater“ that IKEA sells for use with their battery powered window coverings is in fact an answering service device of this type for those battery powered devices.
Anyway, these “answering service“ approaches can really help with battery life: but they are expensive to implement. So you typically don’t see them in devices that retail for under $75. Yet another reason why this can be a good fit for locks and thermostats, not so much for relays and switches, where the price points tend to be much lower.
So… can it be done? Yes, if the device is physically large enough and at a high enough price point. Is it easy? No, the engineering is pretty complicated.
So that’s why you don’t see a lot of them, and usually in specific device classes.
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