Aeotec Nano Switch - state of external switch and use of DPDT switches?

I have just bought myself two Aeotec dual nano switches, which have 2 outputs (OUT1 and OUT2) and 2 inputs from two switches (S1 and S2). I think this applies to the non dual units too though (one out but 2 switches)

When paired with ST I see both outputs as devices - great - I can switch them through ST fine. But I can’t see the inputs from the external switches.

I know there is a parameter to change how the external switch(es) are handled - docs are incredibly opaque about what it does with regard to SPDT (L1 on switch connecting to S1) and DPDT switches (L1 to S1, L2 to S2) …avoiding 2 and 3 way as terms as they dont mean the same everywhere.

Anecdotal evidence suggests that a load on S1 turns on OUT1 and a load on S2 turns on S2 by default but there are options to

a) use a DPDT (and set parameter 121 to 3 way??) and I have seen posts that seem to say that the resultant S1 and S2 simultaneous change has a toggle effect on (both?) outputs, resolving the issue otherwise then you cannot turn the load on remotely and turn it off locally. I can’t see notes on this at all from Aeotec - any experience in this? and for dual switches?

b) it is possible to decouple the external switches from loads (parameter 122) - but where on earth does it announce to (in terms of ST devices/attributes)?

Does anyone have these and can explain how they work or is it just as obvious as S1 on, OUT1 on and vice versa?



[NB I would try to make a rig and test this with the 4 modes and a multimeter but I don’t have the bits and more importantly right now ZWave Tweaker isn’t working in the app, I am waiting in hope that the tiles finally appear in the device rather than the controls for the switch that relate to the default DTH - the settings page works for tweaker DTH but these tiles refuse to appear!!]

@mwav3 has just posted an update to zwave tweaker this week which does work in the new app. :sunglasses:


Awesome, that solves that problem, keen if anyone has experience of these things for advice nonetheless … but at least I can feasibly test it myself and/or set the parameters


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Ok, I had an awesome Aeotec support engineer (this time) who answered everything really clearly - a big thanks to Chris Cheng if he reads this.

For the record (paraphrased questions, pasted answers):

Q: Is it hard linked in mode 1 (2 state) that S1 high = OUT1 on, S1 low = OUT1 off, or it a toggle function?
A: For Dual Nano Switches, it really just matters that it is HIGH voltage to LOW voltage and vice-versa to toggle the output between ON/OFF, doesn’t matter what direction. You could change it to S1 HIGH =OUT1 ON and S1 HIGH = OUT1 OFF, but by default, it toggles regardless of the position since you are also able to control the output via Z-Wave.

Q: Can I check my understanding of how mode 1 (2 state) , mode 2 (3 way) and mode 3 (push button) work in practice as the manual does not clarify the use cases?
A: Mode 1 - Toggle switch type (High → Low or Low → High). Mode 2 - 3-way or you can see this as Momentary NO type (Low → High → Low), the way this method is wired allows it a single toggle on a bridged 3-way circuit to quickly change Low → High → Low. Mode 3 - Momentary NC type (High → Low → High)

Q: Are the states of the S1 and S2 external switches visible:
A: You won’t be able to get the current status of S1/S2, but you can only see the status of OUT1/OUT2.

Q: On the nano switch there is S1 and S2 but one output, on the dual there are S1 and S2 and OUT1 and OUT2. Is the mapping of S1 to OUT1 and S2 to OUT2 fixed or variable?
A: ​On Dual Nano, S1 refers to OUT1 only, and S2 to OUT2 only. On Single Nano Switch, S1 and S2 refer to OUT which you can tie a further 2-way external switch to act like a 3-way. But it is possible to disable S1/S2 control of the load.

Q: (follow on) The parameters for the nano switch indicate that its possible to have the S1 and S2 switches control other devices, not OUT1 and OUT2 (or as well as). How does this work, noting I use ST?
A: This would allow you to directly link S1/S2 to different devices, this is through a more advanced function in Z-Wave that allows you to program a part of the Nano to directly control another device without gateway intervention (must be part of the same z-wave network though). Smartthings doesn’t have this directly exposed, but there are ways to make it work in SmartThings. Other than that, there are a few requirements, such as much be same security level, must be within communication distance, etc. Give you an idea and more of an explanation using our WallMote Quad informational: WallMote Quad - Group Association explanation for direct communication.. Its the same concept and function for S1/S2 control from Nano.

So that cleared everything up!


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