Not exactly, but close.
Z wave forms a “mesh.”
There are two kinds of devices on the mesh: those that can repeat, and those that cannot.
Most mains-powered devices can repeat, including both the dimmer module and the switch.
Most battery powered devices do not repeat because it would use up too much battery life.
Many things can degrade signal strength, including foil insulation inside a wall, large metal objects like a refrigerator, water pipes, Concrete, etc.
The usual rule of thumb for a typical American home is that classic zwave can travel about 40 feet and zwave plus can travel about 60.
The signals are omnidirectional, meaning 360°.
The Hub will send out a signal as far as it can, around 60 feet, since it is a zwave plus device.
At that point, one of the devices that repeats will pick up the message and relay it on to the next group of devices that are more than one hop from the hub.
This continues for up to four hops until the message reaches its ultimate destination.
So…
You need to lay out the “backbone” of your network (the devices capable of repeating) so that there is at least one relay path from the hub to every device, both the ones which can repeat and the ones which cannot.
So assume the hub can send a message about 60 feet, unless you happen to live in an Adobe or Brick house. If it reaches one of your devices in that range, then that one can pass on the message another 40 feet to your other device.
You the human don’t have to do anything to make that happen, it happens automatically with mesh.
More information in the following FAQs:
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