The Devicebook Hub acts as a Z-Wave controller, and natively emits a Z-Wave network. Z-Wave devices in the smart home are configured to connect to this Z-Wave network.
Planning for Z-Wave Devices
Z-Wave networks are mesh networks. That means even if a device is out of wireless range of the Hub, the Hub might still communicate with the device via one or more intermediate devices.
Because Wi-Fi, and Z-Wave are both wireless, we can leverage Wi-Fi signal strength to estimate the range of the Z-Wave network. Since the transmission power of Z-Wave is lower than Wi-Fi, we use lower RSSI thresholds to determine signal strength.
Estimating Z-Wave Signal Strength Around a Home
Follow the instructions listed in this article to use the AirPort Utility App to make note of the Hub's Wi-Fi Signal Strength around the home, in the locations where you will install Z-Wave devices.
But, use this table to
| Wi-Fi RSSI | Z-Wave/Insteon Signal Strength |
|---|---|
| -25 to -35 | Excellent |
| -35 to -45 | Good |
| -46 to -55 | OK |
| -56 to -65 | Poor/Unreliable |
| > -66 | Unusable |
Adding Repeaters
If the signal strength for Z-Wave is in the Poor/Unreliable or Unusable categories, add a Z-Wave repeater node between the device's location and the Hub. Try to position the repeater halfway between the device's location and the Hub's location, with an equal number of walls between them. Check the signal strength at the location of the repeater. If it is still in the Poor/Unreliable or Unusable categories, try to divide the distance from the device to Hub into three sections and use two repeaters. Again, double check signal strength at the position closer to Hub. If it is still in the Poor/Unreliable or Unusable categories, the device's location is too far for Z-Wave or Insteon wireless connection.
For Z-Wave, most AC-powered (mains-powered) devices act as repeaters. Note that too many repeaters near each other (such as a cluster of Z-Wave Light Switches in a single switch gang box) can have the unintended effect of stifling the network rather than amplifying it. Use repeaters as needed, but with enough room between them.
Remember that repeaters and devices must be added in order of network proximity to the hub.
Checking Repeater Signal Strength
Checking Repeater Signal Strength
Unlike the Devicebook Hub, Z-Wave repeaters do not have a Wi-Fi network that you can use to estimate the Z-Wave radio signal strength
Instead, you can use the following instructions to estimate the signal strength of a repeater in nearby areas. You'll be using the Devicebook Hub to simulate the signal of a repeater.
1. Place the Devicebook Hub at the intended location of the Z-Wave repeater.
2. Follow the instructions in this article on another mobile device to monitor the signal strength of the Devicebook Hub's Wi-Fi network as you move around.
3. Place the mobile device at the intended location of a Z-Wave device.
4. On the mobile device, check the signal strength of the Hub's Wi-Fi network. Use the table below to translate the Wi-Fi signal strength into an estimate of the repeater's signal strength. Note that you will get more consistent measurements if you keep the mobile device completely still for at least thirty seconds.
| Wi-Fi RSSI | Z-Wave/Insteon Signal Strength |
|---|---|
| -25 to -35 | Excellent |
| -35 to -45 | Good |
| -46 to -55 | OK |
| -56 to -65 | Poor/Unreliable |
| > -66 | Unusable |
Installing and using Repeaters
House Check Ordering
Z-Wave devices must be “included” into the Z-Wave network in a particular order for optimal network performance.
Specifically, a repeater nodes must be included into the network before any devices relying on that repeater. The path selection for signals to travel from a device to the Hub (identifying the repeater nodes) is done at the time the device is included into the network, based on the signal strengths of all available repeaters.
Note that this means if a Repeater device is moved to a different physical location after inclusion, it is likely to cause issues for other devices relying on it as a Repeater. In other words, any AC-Main powered devices must be included into the Z-Wave network at their final installation location in the home. Battery-powered devices should also be included at their final installation location or close to the Hub for quicker Z-Wave inclusion.
In summary, Z-Wave devices should be set up in House Check in the following order:
- Set up all AC-main powered devices, from nearest to Devicebook Hub to furthest from Devicebook Hub.
- Set up the rest of the battery-powered devices in any order.
Important Z-Wave Installation Practices
AC-powered Z-Wave devices are Repeater nodes. After House Check,
- Do FIX or REMOVE broken devices immediately. Otherwise, the Z-Wave controller will attempt to access the broken devices repeatedly, and will slow down normal working devices.
- Do NOT relocate AC-powered devices after they've been set up.
- Do NOT reset any AC-main powered devices after they've been set up.
- Do NOT power-down any AC-main powered devices after they've been set up.
Limit on Number of Z-Wave Devices
The Z-Wave standard supports up to 232 devices on a single network. In practice, that number of devices is possible, but requires careful inclusion order and placement to accomplish. If a device needs to be relocated, you might have to tear down and setup most of the network again. Our recommendation is to limit a smart home to about 32 Z-Wave devices for simplicity and to limit the time spent to re-establish a Z-Wave network when a device needs to be replaced or relocated.
Next: To learn how to set up Z-wave devices after installation, see Setting Up & Linking Z-Wave Devices in House Check.
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