What radio frequency is used?
The myenergi devices communicate with each other over a low power radio link in the 868MHz frequency (915MHz in Australia, New Zealand)
The "master" device
One device (zappi or eddi) is set to be the "master" device. All the other devices need to be in direct radio contact with this device as shown below.
How far will the radio signal reach?
As with all radio signals, the wireless link between the myenergi devices is weakened if it has to pass through walls or metal objects. In "clear air" the signal will easily reach 25m but this is reduced as soon as there is anything in the way. Foil backed plaster board is a real problem!
What about the hub?
The hub is used to connect your myenergi devices to the internet. They work perfectly well without a hub but it is needed if you want to use the myenergi app or get firmware updates.
Each active device (zappi or eddi) needs to link directly with the hub - unfortunately it's not possible to relay the signals via the master device as this messes up the timing of the different radio packets.
When choosing where to place the hub, try to put it in the middle of all the other devices. The hub has a wired Ethernet connection so is usually plugged directly into your router. If this is not possible then you can use power line carrier plugs to link the hub to the router.