# KNX gateway overload?

**URL:** <https://community.homey.app/t/knx-gateway-overload/55347>\
**Category:** Apps\
**Created:** [November 24, 2021, 12:38pm UTC](https://community.homey.app/t/knx-gateway-overload/55347 "2021-11-24T12:38:26Z")\
**Posts on this page:** 9\
**Page:** 1

<div class="post-metadata">

**Author:** ![Beukenoot](https://avatars.discourse-cdn.com/v4/letter/b/3be4f8/32.png) [@Beukenoot](https://community.homey.app/u/Beukenoot)\
**Post date:** [November 24, 2021, 12:38pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/1 "2021-11-24T12:38:26Z")

</div>

When I start a flow that sets 50 KNX dimmers to a certain dim level always about 5-10 dimmers do not react. The dimmers involved seem to have been chosen randomly. I need to start the flow once or twice again to have all lights turned on.

Now I’m sure that Homey sends them all out. All lighting icons light up in the app. When looking in the bus monitor within ETS however, the lights that are not turned on are missing!

It seems that my KNX IP interface is bouncing some commands, probably because it receives too many of them in too little time.

I was wondering if anyone else has run into the same problem or if someone can think of a possible solution.

---

<div class="post-metadata">

**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\
**Post date:** [November 24, 2021, 12:47pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/2 "2021-11-24T12:47:51Z")

</div>

Homey has troubles with commanding more than X devices in one go, at least with zigbee.  
Maybe setting 50 dimmers at once is too much, either for Homey or the KNX GW.

You can try to delay every group of 5 action cards f.i.  
Like  
THEN…  
set dimmer 1  
set dimmer 2  
set dimmer 3  
set dimmer 4  
set dimmer 5  
set dimmer 6 with 1 sec delay  
…  
set dimmer 10 with 1 sec delay  
set dimmer 11 with 2 secs delay  
…  
set dimmer 15 with 2 secs delay  
and so on.

It’s a bit trial and error, maybe the example can be used for setting 10 dimmers at once, or 15. Then fiddle around with some delays.

---

<div class="post-metadata">

**Author:** ![robertklep](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robertklep/32/160628_2.png) [@robertklep](https://community.homey.app/u/robertklep)\
**Post date:** [November 24, 2021, 1:26pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/3 "2021-11-24T13:26:54Z")

</div>

> [@Beukenoot](#):
>
> Now I’m sure that Homey sends them all out. All lighting icons light up in the app. When looking in the bus monitor within ETS however, the lights that are not turned on are missing!

So how do you conclude that Homey sends them all out? It seems to me that Homey _thinks_ it sent them all out, but it didn’t.

As already pointed out by @Peter_Kawa, Homey isn’t very good at sending multiple commands from a flow at the same time, commands get lost somewhere in Homey (and since this issue has existed for such a long time now, apparently Athom cannot fix this).

---

<div class="post-metadata">

**Author:** ![Beukenoot](https://avatars.discourse-cdn.com/v4/letter/b/3be4f8/32.png) [@Beukenoot](https://community.homey.app/u/Beukenoot)\
**Post date:** [November 24, 2021, 2:17pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/4 "2021-11-24T14:17:35Z")

</div>

Wow, I didn’t know that. This affects the robustness of the app so much and it seems so unlikely to me that it would be hard to resolve. Maybe just a general setting of a delay between commands or something like that might help.

---

<div class="post-metadata">

**Author:** ![robertklep](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robertklep/32/160628_2.png) [@robertklep](https://community.homey.app/u/robertklep)\
**Post date:** [November 24, 2021, 2:43pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/5 "2021-11-24T14:43:21Z")

</div>

I don’t think Athom has even acknowledged that this problem exists, even though a lot of Homey users run into it. The issues started with Homey firmware v2, where Athom rewrote the flow handling. That was 3 or so years ago. Given that the issue still exists, I have to conclude that Athom is unable to fix it, and unwilling to implement a general workaround.

---

<div class="post-metadata">

**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\
**Post date:** [November 24, 2021, 4:24pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/6 "2021-11-24T16:24:28Z")

</div>

Two more workarounds:

> [@Switching on zigbee lamps (serie of 10) slow all of a sudden](https://community.homey.app/t/switching-on-zigbee-lamps-serie-of-10-slow-all-of-a-sudden/47469/3):
>
> A way to avoid delays of _whole seconds_ is to create 3 flows which control 1/3 of the lights each.  
> Flow 1 switches on say 3 lights and starts flow 2  
> Flow 2 switches on another set of 3 lights and starts flow 3  
> Flow3 switch on the last set of 3 or 4 lights .  
> Flows are started x msecs after eachother, which is a lot quicker then adding a delay of 1 sec between every set of 3 lights.
> 
> Another option is to use the [\< group \> app](https://homey.app/en-gb/app/com.swttt.devicegroups/%3C-group-%3E/). It can group anything with similar possibilities, like dim, on/off & hue etc. etc.  
> It has a build in option, to switch every item in the group with a little delay in between every device. It’s adjustable per msec.  
> So the action card becomes one card

---

<div class="post-metadata">

**Author:** ![Beukenoot](https://avatars.discourse-cdn.com/v4/letter/b/3be4f8/32.png) [@Beukenoot](https://community.homey.app/u/Beukenoot)\
**Post date:** [November 29, 2021, 3:22pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/7 "2021-11-29T15:22:07Z")

</div>

Thanks for the tip! Using the app with a 100ms delay seems to be a work around for a Homey bug.

---

<div class="post-metadata">

**Author:** ![robertklep](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robertklep/32/160628_2.png) [@robertklep](https://community.homey.app/u/robertklep)\
**Post date:** [November 29, 2021, 3:27pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/8 "2021-11-29T15:27:47Z")

</div>

Does using 3 separate flows actually work around the problem? Because you’re basically starting 3 flows within milliseconds of each other, and each flow is switching 3 lights, so you still have 9 or 10 lights being commanded at _almost_ the same time.

---

<div class="post-metadata">

**Author:** ![Beukenoot](https://avatars.discourse-cdn.com/v4/letter/b/3be4f8/32.png) [@Beukenoot](https://community.homey.app/u/Beukenoot)\
**Post date:** [November 29, 2021, 5:47pm UTC](https://community.homey.app/t/knx-gateway-overload/55347/9 "2021-11-29T17:47:19Z")

</div>

I didn’t try that but if there is a delay of x msecs before a flow is started, this might very well work. For me though, this would be too much work and my flows would become too complex and hard to maintain.
