Changing ZigBee channel


(Kai Hansen) #1

Hello,

I’m having some potential issues with device congestion on my WiFi network. I’m aware that changing the WiFi routers channel to 1 or 11 can help with this, but I’m wondering if there’s a way to change which of the 16 ZigBee channels the ST’s hub and connected devices use.

Thanks


(Duncan) #2

Sorry, there is currently no way to change your hub’s ZigBee channel. We only use channels that don’t overlap with WiFi channels, however.


(Ronny Carr) #3

This is a major issue for me, almost daily I have zigbee dropouts, causing my apartment to think I left, shutting everything down.


(Nathan Meryash (Keen Home)) #4

Hi Duncan,

Is this still an up to date answer? We’re working on a device that has stronger TX power on certain channels. This means while it may support all 16 ZigBee channels, not all channels may offer a strong enough signal to pair to the ST coordinator reliably depending on the users environment (competing channel traffic, walls, etc.). We’re not the first to do this, Nest also has different power settings depending on the channel.

Can you lend some insight as to how automatic channel selection is handled? Search for quite channel? Random? Search for strongest signal with first endpoint or node paired?

Your insight is greatly appreciated as is any additional control you can offer on channel selection from a feature standpoint in the future.

Thanks,

-Nathan


(Duncan) #5

I think there’s been some work done around scanning for the best channel when the hub is set up, but as far as I know we’re currently still assigning a random channel at manufacturing time from the set {14, 15, 19, 20, 24}.

cc @steriana


FAQ: Networking and Reducing Channel interference between WiFi and Zigbee
SMC Zigbee Devices (Xfinity Home)
(Nathan Meryash (Keen Home)) #6

Thanks for the quick reply Duncan. Yes, any additional visibility and or control around this area is on our wish list.

One recommendation is to try and avoid the selection of channel 24. The reason being that most devices using a +20 to +30dB PA do not offer anywhere near their full power on 24 (this is not unique to us). The reason being that full power TX on channel 24 results in out of band harmonics and is thus attenuated to pass FCC.

-Nathan


(Scott G) #7

I just wanted to add that there is a lot of interest for this from the user base as well to help us manage our individual home networks better. I’ve read a lot on here that performance with ST can be considerably diminished by our device setups and interference, but we aren’t offered any control of the protocol on the most used frequency. Just my 2 cents…


(DLee) #8

@Ben any word on how Hub v2 will handle Zigbee channel decision? Is it luck of the draw from a permanent factory channel setting? Also, is the current v1 hub locked into one channel as Duncan speculated above? Or did recent hub updates put some smartness into channel selection?

Ideally we would be able to select the best zigbee channel for our environment.

After another round of smartsense motion issues last month I did some research. With my hub on zigbee channel 20 and wifi router on 11 everything seems fine (My neighbors have saturated 802.11 channels 1 to 6.).

Helpful tidbits on why this can matter if you experience zigbee sensor weirdness:



http://www.digi.com/wiki/developer/index.php/Channels,_Zigbee


#9

I believe that’s channel 26,not 24.


#10

My two cents: Interference between wifi and zigbee is practically a non issue these days. For example, at CES over the last few years, people have been unable to get their wifi devices (old but it demonstrates the point: http://blogs.reuters.com/mediafile/2011/01/06/ces-please-turn-off-your-phones-and-your-wi-fi/) to connect at all, but the zigbee products were working great. Since then, more wifi devices have shifted to newer revisions and 802.11G, N, etc. actually make it easier for zb networks to share the frequency band compared to 802.11B (faster data rate so more quiet time for zb devices to talk).

Of all the things to look at for making the zb networks/devices more reliable right now, I would put channel selection at the bottom.


Wall Switches?
(Duncan) #11

The current plan is for Hub v2 to scan for the best channel when you first set it up. A utility to change the zigbee channel will be added at some point, but there’s no timeline for that.


(DLee) #12

I agree. But twice in nine months I had some simultaneous Zigbee motion sensor network issues and also occasional random missed motion event logging. Being able to change the zigbee channel could help with troubleshooting. In a typical home environment it may be a necessity to have one or more zigbee devices or even the hub closer to the wifi router than ideal. More tools to troubleshoot random issues and narrow down potential sources of the problem would help.


(Kristopher Kubicki) #13

Just for posterity: Pairing a Hue bulb directly to ST when the Hub is on channel 14 is a death sentence for the bulb. The Hue hub has no channel 14 so if you pair onto 14 you cannot get back onto 11, 15, 20 or 25 on the Hue bridge.


(Joe) #14

It’s definitely an issue still. I have the Phillips hue hub to compare it to. Switching to channel 19 everything on the Phillips hub becomes 100% reliable. When on channel 20 reliability drops noticeably worse. It starts behaving like the smarthings does. This smartthings is locked to bad channel 20.

By the way channel 20 overlaps with wifi 7,8,9 & 10, but I know interference is not as likely an issue as subtle propagation characteristics within building materials. A difference between 12.236cm (20) and 12.261cm (19) can make all the difference when bouncing around Air conditioning vents, appliances and metal door frames.


(Eric) #15

Would love to know the latest on this. @duncan


(Alix) #16

Any news on this, 2 years later?


(Eric) #17

I doubt this is going to happen, they don’t have the resources. They don’t even have time / resources to allow people to opt out of the LAN discovery or add modes in the mobile app. Wait, they had time to build an Apple Watch app? What?

It’s about acquiring new customers, not keeping existing customers happy as we have already given them all the money ware are going to give them (partly because their devices are overpriced and not as good as others).

They know there is no where else to go.

If they had a migration tool, I’d consider rolling the dice and just buying a new hub in hope that I would get a different zigbee channel.


(Sean) #18

any movement on this feature yet?


(Srihari) #19

Hey Duncan,

What is RX sensitivity of the ZigBee radio in the hub ?

TIA


#20

Duncan is a senior zwave engineer. I’d suggest asking @tyler or @tpmanley instead. :sunglasses: