Somfy, which motor to choose, WT or RTS?

[Ron]

In the near future we wil order a sunscreen with a Somfy motor.
We use Domoticz, a RFXtrx433XL transceiver (has Somfy in it) and a USB Aeon Z-Wave plus transceiver.

Which motor would you choose:
WT (wired) motor controlled by a Qubino or Fibaro Z-Wave rollershutter
or
RTS motor with wireless connection to the RFXtrxXL

I would like to hear your comments on both of these...

[hoeby]

I have screens and curtains from somfy.
Both with RTS motors.

I have chosen for this, so i can use the default somfy remote. My wife doesn't do all with domoticz/automation.

I use it with a RF-link, Works beautifull.

Is the wired solution also a somfy motor?
Or something you have to assemble yourself?

[Ron]

The wired (WT) motor is a Somfy motor with 5 wires, live/neutral/ground/up/down.
The up and down movement can be controlled by a simple switch or with a Z-wave shutter controller (2 relays)

[b_weijenberg]

I made a mistake, i meanth RTS motor, not RFT.
(changed my previous post)

The wired (WT) motor is a Somfy motor with 5 wires, live/neutral/ground/up/down.
The up and down movement can be controlled by a simple switch or with a Z-wave shutter controller (2 relays)

You can control the Somfy RTS perfect with the RFXtrx433XL and receive and control other 433.92MHz devices with the same RFXtrx433XL.
You can for example use 433.92MHz sensors, control Somfy RTS, Dooya/Brel motors and connect a P1 interface in addition all with the same RFXtrx433XL.

[Ron]

Thanks, that was also what i would choose at first.
I was mislead by a webshop who advised to use a Z-Wave wired rollershutter as these would be more reliable als the RTS motor...

[hoeby]

The only thing i could think about not using a RTS motor, is for the delay in commands. But i don't know if this has something to do with the RF-link or somfy.

I controll 2 curtains, each has his own motor.
When i send 2 commands from domoticz, 1 for each motor. There is 3 seconds between the first and second command. Not a problem for me. Zwave should be quicker.

[Egregius]

Isn't it so that with RTS you can only send open/close? And you don't know the real status in domoticz when the remote is used?
With a Fibaro roller shutter you can also send percentages wich work really good.
When I installed motors in the blinds I specifically asked for motors with open/close wires.

You can then still use a remote to send commands to the Fibaro.
I use Remotec scene masters for that. Another advantage of that is also that you can program the buttons so they do stuff depending on other devices or time of day etc.

[b_weijenberg]

The RFXtrx can also send an intermediate position which can be set as a fixed intermediate position in the motor.
To set any other position you can use a timer, transmit an up/down command, wait x seconds till the end position is reached, transmit a down/up command and transmit a stop command after x seconds.
Beside this you can transmit enable sun/wind sensor and disable sun sensor.

[rrozema]

For anyone reading this to choose between using RTS or a Z-wave switch for their blinds. First of all one important factor is of course if you've got the hardware set up in Domoticz. To be able to use z-wave you need a z-wave controller (usb stick most of the times) and to be able to use RTS you need some sort of RFX controller. I only have z-wave with no RFX controller available to me, so for me the choice for Z-wave was easy. If you've only got RFX with no z-wave controller RTS may still be more appealing to you.

Here are some of the differences between RTS and Z-wave that you should consider when choosing if you've got both or still need to decide which controller to get.

• The somfy RTS protocol does not provide feedback to the controller (=Domoticz), meaning that if the blind was moved by any other means than instructed by Domoticz, the status for the blind in Domoticz will still show the old status, and a mismatch may exist with the actual blind's position. Z-wave does provide feedback and your Domoticz will always show the correct position of the blind.
• Because RFX does not provide any feedback, some commands may be missed, and as a result, the blind may have changed status in Domoticz, whereas the actual blind didn't. Z-Wave automatically retries any missed commands (up-to some time-out) and thus you will not have missed commands with the z-wave switch.
• Most z-wave blinds switches will allow you to specify any new position as a percentage of the full range from opened to closed. This provides for a very easy interaction with the blind: just set the new position. RTS is said above to support some pre-defined set-points, these are however not easily available from Domoticz and thus does not provide the same ease of use that Z-wave does.
• Setting a blind to a specific position using RTS/RFX requires exact timing: you start the blind motor in either direction, then wait X time before sending a stop-command and the blind will be in the desired position. However Domoticz runs in a multitasking environment and timing can be less precise because f.e. another process got priority over your process timing the blind's run time. Your blind's positioning may be off somewhat using RTS. The z-wave switch does the timing internally, so the positioning will be more reliable.
• Setting the new position using a z-wave switch is easier to use than having to time when to stop moving with RTS, but it does make that you can not start the blinds movement, then to 'stop' the movement while the blind is in transit like you can with RTS/RFX. With Z-wave the device in Domoticz will already be at the newly specified position, even though the physical blind may not arrived there yet. In some ways the different control of the device is an advantage, in others a disadvantage. Your choice...

[BartSr]

I am having Zwave as well as 433Mhz devices at home.
From experience I found that Zwave is not that reliable all the time. It can be running fine for weeks and out of the blue stop working giving lots of work to get it back to work.
433Mhz is mostly, but also not always, running fine. Have no experience in hooking up the Somfy devices to Zwave but using 433Mhz RTS is as easy as you can imagine. Just unplug the screen, wait a few minutes. Meanwhile create a manual switch and after plugging in the screen again (screen reacts by up/down movement) press test button of your custom switch in Domoticz and it's all done.

-Bart

[rrozema]

I am having Zwave as well as 433Mhz devices at home.
From experience I found that Zwave is not that reliable all the time. It can be running fine for weeks and out of the blue stop working giving lots of work to get it back to work.
433Mhz is mostly, but also not always, running fine. Have no experience in hooking up the Somfy devices to Zwave but using 433Mhz RTS is as easy as you can imagine. Just unplug the screen, wait a few minutes. Meanwhile create a manual switch and after plugging in the screen again (screen reacts by up/down movement) press test button of your custom switch in Domoticz and it's all done.

-Bart

As far as I know the Somfy devices can not be told to 'go to position x' (other than maybe a pre-defined stop), like the z-wave devices can. This is because the protocol was not meant to be used for automation purposes: any needed feedback would be provided by your eyes: f.e. you press 'down' and wait until you see the blind has reached the desired location and you press 'stop'. Domoticz doesn't have your eyes to see if the blind is at the correct height, so it can only keep track of the time before it needs to send the 'stop' command. Just for comparison, blindfold yourself and then try to set the blind at some desired height using the remote: that's the task Domoticz has for these RF devices. And this is what makes the protocol inherently less reliable for automation purposes. Small (timing) errors will add up over time until at some point the device's state significantly differs from that which Domoticz thinks it has and your automation fails. Including new RF devices may be easier than z-wave devices, but you only include your devices once so it's much more important that they're easy and reliably during their use.

The Z-wave protocol is therefor more reliable than RF 433MHz because of the feedback mechanism built into it: after a command has been received, receipt is confirmed by the device and if a command is not confirmed in time, the command is automatically re-sent. Plus, if some z-wave device changes state it can inform the controller of it's new state by sending a message to the controller. Most modern z-wave devices all send out such "unsolicited" information messages, only some very old z-wave devices may still require polling. Most RF 433MHz devices do not have anything similar and so any lost command needs to be re-sent by the controller or the state of the device and it's image in Domoticz will be out of sync. But, since there is no feedback mechanism, Domoticz has no way of knowing that it actually is out of sync. Also the only way for Domoticz to learn that a RF 433MHz device has changed state is by periodically querying each device to return it's state.

The fact that your experience with z-wave is less than satisfactory most likely has one of these reasons:
- Domoticz has a flaw in its z-wave implementation where the capabilities of nodes are ment to be cached in an xml file, however this xml file can easily become (partly) invalid when domoticz gets stopped before z-wave has been fully initialized. If this happens it can be a lot of work to get all nodes properly known to Domoticz again (you need to have Domoticz re-query node information for each of the nodes and maybe even re-include some nodes to fix this). This is however a problem in Domoticz, not in the Z-wave protocol and it can mostly be avoided by taking care never to stop Domoticz before z-wave has been fully initialized.
- Zwave, being a mesh network, needs to keep information how to route messages over the nodes in the network. Z-wave nodes and controllers initially learn the routing information when they learn about new nodes, during inclusion. For this reason it is wise to always include new nodes at or near where they will be installed and not at some "test location" like on your work bench. If for any reason you do need to move an already included node to another location, always remember to 'heal' the network's routing information once the node is in its new location. Also here, Domoticz' implementation of the healing process can be a little unreliable so you need to give it enough time to perform the network healing process: I suggest to limit sending out commands as much as possible after you've initiated the heal network process for at least 30 seconds times the number of routing z-wave devices (~ mains-powered devices) in your network: so if for example you've got 30 mains-powered z-wave nodes, wait at least 15 minutes before you actively start using your devices again. Plus make sure that you've got redundant paths between your nodes.