How your PC Z-Wave controller affects routing...


Active Member
I haven't seen this topic discussed anywhere before, so I thought I'd throw this out as a bonus to all Cocoon'ers :p

When you add your PC Z-Wave Controller (USB, RS232, etc.) to your Z-Wave network, it (unless it's the special portable version) becomes a routing node. That means that Z-Wave commands are being routed through your PC Z-Wave Controller just as they would be through a light switch on the wall or a plug-in module.

This has (at least) three effects:
1. If your PC Z-Wave Controller is the _only_ Z-Wave node between two other ones which are not in direct range of each other, and you turn off your PC, you've removed their ability to route to each other. So trying to turn on or off a device from your remote or a routing slave (i.e. scene controller, transmitter switch) might not work if your PC and its USB port power was turned off. This is not necessarily common, but it's something to keep in mind.
2. If you turn off your PC (and its USB port power) and use a controller (or a routing slave) to communicate with any device which is expecting your PC Z-Wave Controller to be there as a repeater, you've potentially slowed down parts of your Z-Wave network.
3. If you have your PC Z-Wave Controller plugged into a portable PC, and you move it around while adding nodes (or after you've added nodes), this will also potentially introduce slow-downs into parts of your Z-Wave network (since many nodes think it's in many places!)

The morals of this story are:
1. Z-Wave has built in intelligence to deal with situations like this (as long as there are other nodes in range to repeat)--but moving around your PC Z-Wave Controller is not a good idea (unless it's the special portable version).
2. If you are having troubles controlling your devices with a handheld remote (or with a routing slave), turn on your PC to see if maybe you need another node there; as a side note, with routing slaves like virtual switches and PIRs, if you need to re-establish the connection and you're not going to have your PC on all the time, turn it off if it's convenient beforehand.
3. If you need to clean up a mess you have already made by moving around your PC Z-Wave Controller, simply re-add all the nodes (no need to remove them, in theory), or ask nicely and I'll see if I can get you in on the beta for software tools we have which can fix those issues.

Some great tips and advice, thanks Chris! I think most people leave their HA PC on 24/7, so hopefully they won't run into that problem.
Sort of. I've been known to attach an x10 controller to a laptop that moves around the house. With a laptop, Smartome's 1132CU interface and their Smarthome Manager software, I can quickly verify signal strength in a location, install a wired switch, then program it with scenes and ramp rates. That way I don't have to keep crossing the house to the main HA computer to set things up. I also use the laptop as another full-function, wired remote control wherever I need it.

I think his point is that if you try to do the same with released versions of Zwave you'll run into trouble.

So does this mean if you use a powered USB hub, you can turn your PC off and still get full Z-wave routing? Or do self powered hubs turn themselves off along with the PC?
USB ports are normally shut down, but most motherboards have a jumper which allows certain USB ports to stay powered up after shut down (I use this so I can turn my HTPC back on with my remote, which uses a USB receiver).