Page 1 of 1

Z-Wave, Handshake and reliability

Posted: Saturday 06 April 2019 10:03
by Patricen
I know there is a handshake for z-wave protocol and I'm wondering if Domoticz uses it.
I do have several Popp radiator control valves and I mentioned that those that are connected through a repeater / extender are less reliable than those that are directly connected to the controller.
Is there a way checking the setpoint has really been applied to the device and if not resend the sertpoint?
Thx!

Re: Z-Wave, Handshake and reliability

Posted: Wednesday 10 April 2019 10:40
by lost
Patricen wrote: Saturday 06 April 2019 10:03 Is there a way checking the setpoint has really been applied to the device and if not resend the sertpoint?
Retry should be done automatically if the acknowledge is not received. Take care default retry time is several ten's of seconds (to avoid re-sending data on slow devices/z-wave networks).

See retry timeout there:
https://github.com/OpenZWave/open-zwave ... ig-Options

So, when you experience timeouts in log for the device as well as unchanged setpoint, a retry have already been done and was not effective...

If you have lots of scheduled items at the same time, you may also distribute schedules over a few minutes. This may avoid some low-z-wave bandwith saturation problems.

Re: Z-Wave, Handshake and reliability

Posted: Wednesday 10 April 2019 17:42
by Patricen
Thanks for this valuable input!
If I do understand well, there is only one retry that is performed if handshake is not received.
I'm going to try changing timeout.
I do have only one setpoint that fails updating regularly, it might be the setpoint device that is defective (popp trv).

Re: Z-Wave, Handshake and reliability

Posted: Wednesday 10 April 2019 20:10
by Patricen
This looks promissing, the "RetryTimeout" parameter was set as a comment by default in the Domoticz config file.
I removed the comment code and set the parameter to 40000 milliseconds
Up to now I programmed setpoint changes every 5 minutes (10 changes in total) without any failure.

Thanks!!

Re: Z-Wave, Handshake and reliability

Posted: Tuesday 16 April 2019 13:40
by vinisz
40000 is the default already, so, when not putting in this parameter, 40 seconds should already be in place. (see: https://github.com/OpenZWave/open-zwave ... ig-Options)

Do you think different about that ?
Patricen wrote: Wednesday 10 April 2019 20:10 This looks promissing, the "RetryTimeout" parameter was set as a comment by default in the Domoticz config file.
I removed the comment code and set the parameter to 40000 milliseconds
Up to now I programmed setpoint changes every 5 minutes (10 changes in total) without any failure.

Thanks!!

Re: Z-Wave, Handshake and reliability

Posted: Tuesday 16 April 2019 19:08
by Patricen
Hi,
It looked to me that the default value is 40secs provided the option is not set as a comment, but as you said it might be different.
I felt that removing the comment sign improved the situation but it can be a bad feeling...

Re: Z-Wave, Handshake and reliability

Posted: Tuesday 23 April 2019 9:34
by vinisz
Well, I would say a "default" means that that values applies if nothing else is set, but hey, I'm not 100% sure either....
I'll try to test with it as well, see what comes out...