Multipurpose sensors range

Would that be possible on both Hue and ST?

Yes, you can check the channel both are on (for ST in IDE, for Hue in the app), but you can only change the Hue channel. In the Hue app, go to settings, select your bridge, then click the information “i” icon. There you will see the zigbee channel and can change it. For ST, login to IDE at then select Locations, select your hub, and then look at the zigbee section to see the channel. I have my Hue bridge set to channel 11 because my ST came on channel 20.

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Thanks, I just checked and I have ST devices using channel 20 and Hue on channel 25.

And what channels, if any, do you have your 2.4 WiFi on?

WiFi is on channel 11, but I also tried to switch off the access point completely.

Update: I ordered and installed a ST power outlet and put it almost next to the hub.

Now the door sensor works even if I’m outside. What does it mean? Is there something wrong with the hub?

Is the hub inside of any kind of cabinet or near any other electronic devices? How many zigbee devices are connected to the hub?

The hub is fairly distant from other devices. I have tried different positions, different angles, different rooms.

At the moment, I have 3 devices connected to it (one motion sensor, one multipurpose sensor, 1 outlet plug). No matter how many devices I use (even only one), the reception I get is horrific.

As I said, the outlet plug I just purchased is sitting almost next to it and it getting the signal from other devices even outside the house.

If it turns out it’s a faulty antenna, I will see if I can solder an external antenna to the Zigbee internal one.

I know that this was a used item from eBay, but given that I’m an IT engineer, I would be bankrupt if I had to buy brand new every time I wanted or needed to experiment with something.

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If you change the length of the antenna, you will almost always start losing messages and get worse reception. This is just physics. It has to do with a concept called “resonant frequency.“ antenna length is generally designed to very precise specifications, particularly in lower power devices like those in home automation.

I doesn’t necessarily need to be of a different length, but there is obviously something not right about the signal that the hub receives.
I know it won’t be perfect, but what I have now is a device that is not capable of receiving a radio signal behind a wall.


There are two likely possibilities. And both could also be true.

  1. The hub itself is defective. Speaking as a field technician, by far the easiest way to test this is just to buy another hub and see if that fixes the problems. Buy it from someplace with a good returns policy and you can return it if it doesn’t work.

  2. there is a local interference drowning out the Zigbee signals. This does happen. And it might very well affect your smartthings Zigbee network but not your Hue zigbee network if they are on different Zigbee channels. (Or the Hue system might be creating interference for the SmartThings system.)

What channel is your smartthings hub on? Many zigbee coordinators are smart enough to select a channel with low interference, or even have channel hopping capabilities, but the smartthings hub is not one of these. There’s no way to change its zigbee channel except by resetting the hub and then it just randomly picks a channel which could be the same one you just had. :scream:

Anyway, start by reading the following FAQ:

FAQ: What WiFi Channel is least likely to interfere with SmartThings?

Also remember that the smart things hub is a single plastic box that has multiple radios inside, and even some of those can interfere with zigbee. (I know, it’s tricky.). The radios are Omni directional and the signal spreads as you move out away from the box.

It’s not at all uncommon that you get the strongest connection to an end device about 3 m away from where the hub is. A lot of people make the mistake of putting a device they are having trouble connecting right on top of the hub or right next to the hub, and that’s often less successful than moving it farther away. (Again, physics.)

And in particular, you want your Zigbee devices at least 3 m from any high power Wi-Fi transmitter, including your WiFi router and any access points.

I have previously posted about a situation we had at my house where when we put a Wi-Fi extender on one wall, all the zigbee devices to the east of it fell off the network. We moved it 90° to a different wall, and everything was fine. Physics. :sunglasses:

The hub is on channel 20, Hue channel 25.

I get what you say, but what I don’t get is how the outlet can get (and repeat) the signal of the sensor and the hub can’t.

I am almost convinced that the problem is with the hub, but rather than spending money on a new one, I will probably keep the outlet plug near the hub so that it can get signal from other devices.

What really bothers me is not knowing what actually is wrong with the device…

It appears that there are some platform issues going on right now which might also affect the results that you were

New incident: Investigating
Some users in the Americas may be experiencing issues with their hub going offline and losing control of hub-connected devices. Affected users may also experience failures in automation execution with automations that utilize those hub-connected devices. We are currently investigating and will provide updates as available.

Did you get a chance to read the channel interference FAQ yet? In particular:

WiFi Channel 11 happens to be far from zigbee channel 11, but it is sitting right on top of zigbee channel 20.

Try changing your Wi-Fi channel, that may fix the issue.

As far as why the sensors can communicate to the pocket socket and not to the hub, how far is the smartthings hub from your Wi-Fi router? And, yes, sometimes just moving a device by a couple of feet will make a difference.

I didn’t change the channel because channels 1 and 6 are overcrowded here, so I would have a slower connection with the WiFi, but I did try to switch the access point off completely, just to rule it out.

The hub is approximately 2 metres away from the access point (although as I said I did try to switch it off), funnily enough the plug is even closer.

That being said, what I see is a low value of RSSI even when the sensor/plug/remote device is sitting next to the hub (-77 was the best I was able to get, ever).
If it was an interference issue, shouldn’t the RSSI still be fairly high and the LQI low?

Those zigbee route statistics in the ide can take up to 24 hours to update.

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Well, I received the multi-purpose sensor yesterday and set it up. I’m not terribly impressed with the setup process in the new SmartThings app - finally had to use the Classic app to add it. It’s about 20 meters straight line and passes through 3 walls, but appears to be working fine. It’s reporting a RSSI of -58 dB right now.

I’ve been reading your updates, and I’m really curious as to what’s the issue. One thing that may be worth experimenting with is to see if relocating the plug farther away from the hub will still work.

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Well, I tried to put the plug in the kitchen, where the sensors originally couldn’t communicate with the hub, and I got the same problem.
The plug and hub are now in the same room, approx. 1 metre from one another, and the signal I get from the plug is -71.
The signal that I get from one of the sensors that is in a shed downstairs (at least 3 walls between them), is again -71 but that’s because it reaches the plug first (I am not sure if I can check the signal that the plug itself gets).

So the problem I have is that the hub, for whatever reason, has got a useless reception.

I opened it and it looked pretty much okay to me, no obvious defects.
The Zigbee chip itself is working, otherwise it wouldn’t process the Zigbee radio signals, what probably isn’t working is the antenna or whatever provides good reception.

When I have some time, I will check if the circuit of the antenna is not interrupted somewhere in between.

I forget, is the hub out in open air? Or in some kind of cabinet?

The hub is on a table, but I tried different locations and different rooms.