What is Z-Wave?

Is Z-Wave two-way?
Most Z-Wave products are two-way, allowing wall-mounted controllers and software to be aware of whether lights are on/off or dimmed throughout a network. We can even report the lighting intensity level for an individual device. This means when you push a button on a wall-mounted zone controller, you will get an indication on the controller when the lights (often in other areas of the home) have turned on or off, accurately. The alternative is to blindly send a command from a controller and trusting that the system performed as expected.

Is Z-Wave reliable?
Z-Wave is very reliable. Every command sent to a receiver is acknowledged by the receiver. If the transmitter doesn’t receive the acknowledgement from the receiver it resends the command. If there is still no acknowledgment the command is routed to the intended receiver using other Z-Wave devices to relay the command. As long as you have a Z-Wave device every 30 meters or so you will have no problems with communication reliability. The products themselves are also very reliable, we are working with the best in class manufacturers in each product category. Leviton, Cooper, Intermatic are all companies that have been in the residential lighting business ever since electric lighting was invented. Harmony and UEI are the leaders in universal remotes. All these products are very reliable and well supported.

How does Z-Wave compare to X10?
X10 is a lot like learning BASIC. Everyone has used it, and once they learn it, they have learned not to use it again. Seriously though, X10 is ideal for simple applications such as controlling a lamp across the room. It runs into reliability problems when the installer begins thinking of X10 in a whole-house installation. The more X10 products that are installed in a home, the less reliable the system becomes. Z-Wave is the opposite: More Z-Wave components installed in a home increases the reliability of the entire system.

In what countries is Z-Wave supported, and at what frequencies?
Z-Wave operates on a variety of sub-GigaHertz frequencies throughout the world:

  • Australia: 921.4 MHz
  • Brazil: 921.4 MHz
  • CEPT*: 868.4 MHz
  • China: 868.4 MHz
  • Hong Kong: 919.8 MHz
  • India: 865.2 MHz
  • Japan: 951-956 MHz
  • Malaysia: 868.1 MHz
  • New Zealand: 921.4 MHz
  • Russia: 869.0 MHz
  • Singapore: 868.4 MHz
  • South Africa: 868.4 MHz
  • UAE: 868.4 MHz
  • USA/Canada: 908.4 MHz

Does anyone make Z-Wave compatible products that are 220V that work in Europe?
At this time the only 220V Z-Wave products are from ACT. Look for many more 220V products from EU companies to come to market mid-2007.

What is the modulation in Z-wave?
The modulation of Z-Wave is FSK in the 900MHz ISM band.

What are the pros and cons of Z-Wave vs. UPB PLC systems?
UPB uses the power wiring to transmit its signal so it cannot be used for portable and battery operated devices. UPB products are limited to a few manufacturers, and to date, only lighting products. Z-Wave products are manufactured by over 40 companies and cover products such as Lighting, Window Coverings, Touch Screens, Alarms, Motion Detectors, Universal Remote Controls and support from several Home Control management platforms and software.

UPB can be very reliable but in most cases requires a bridging device to be placed in the main circuit breaker panel in standard 120/240V split single-phase power systems. Z-Wave on the other hand uses a robust mesh network strategy where every device can act as a repeater ensuring full coverage of large spaces without the need for bridging devices.

Also, as UPB devices are installed in a network the signal strength on the network decreases with each one due to loading of the power line. With Z-Wave, the more devices installed in the network the stronger the mesh is.

Can you mix and match Z-Wave products and controllers?
Absolutely. The Z-Wave standard requires all products to maintain basic interoperability with all other products. For example, you can rest assured that all Z-Wave remotes that can control light switches will be able to turn on or off light switches from any vendor.

With that in mind, Z-Wave products vary in their features (just like with Bluetooth and other standards). This means that some simpler remotes may only understand how to control lights and blinds, for instance. Also, manufacturers may add extra features that go above and beyond the basic functionality; if that’s something you need, simply buy a remote that understands how to take advantage of those extra features.

Is there a need for a central controller in a Z-Wave lighting system?
No. That’s a major value of a mesh network. Other lighting control systems that have been on the market for a while have relied on a centralized lighting cabinet. All lighting circuits require wires that lead back to this cabinet, and all control functions (scenes, zones, intensity) are controlled inside this cabinet. Use wall-mounted switches, dimmer and controllers to operate the system. But, everything is hard wired back to one control cabinet. Z-Wave eliminates the centralized cabinet requirement, thus dramatically lowering the costs, by allowing each device to become an intelligent transceiver: sending and receiving command information wirelessly. Putting all these individual intelligent devices into a home makes the entire system more reliable, efficient and scaleable. It also allows the products to be used in retrofit and new home construction with equal results.

How does a controller know what Z-Wave devices are available in a room, in a space, and in the whole house?
To set up a Z-Wave network, you typically walk around your home and add each device to the network by pressing “add/include” on the Z-Wave remote and pressing a button on (or turning on) each device. The remote then remembers all the devices available to it in the home. When you add another remote to the network, the master remote simply passes this list along.

With many remotes, it’s possible to assign devices or groups of devices to individual push buttons. This way, you can set up lighting scenes or other advanced remote control functionality in a home. Also, some remotes and controllers can visually group devices into individual rooms or areas in the home.

If my switches are too far apart to communicate directly, is there a range extender that I can use to fill in the gaps?
Every Z-Wave device acts as a repeater automatically (with a few exceptions, such as battery operated devices). If you have gaps in your network, simply fill them in with Z-Wave electrical outlets or plug-in modules. “Repeater only” devices are expected in the future.

Are there any light switches that are battery operated and if so how long will the battery last?
There are many battery operated handheld transmitters like the Intermatic HCA09 or the Monster AVL300 that can be used to switch lights and other things on and off. However, it sounds like you want to know if there are any in-wall mounted, battery operated transmitters that could be used to “fake” a light switch and be mounted where there is no wiring available. Sadly, the answer is no, not at this time. This is a popular product configuration and we’re certain it will not be long before one or more of the companies building Z-Wave enabled products will put one on the market.

Will my Harmony 1000 remote control up to four different Z-Wave switches? Is it easy to program? Where can I get switches?
First, the Harmony 1000 remote will directly control your Z-Wave switches. It’s also easy to program. Log on to Harmony’s web site and set up your control menus and scenes, and download that to the Harmony 1000. Then use the Harmony 1000 to create a link between each of the logical devices (the ones you created menu items for on the web site) with the actual physical switches in the room. This is a push the button process. You’re done, sit back and enjoy. Switches are currently available from Intermatic , Wayne Dalton , ACT, Monster , and Leviton. They will be available from Cooper Wiring Devices and Jasco-GE in the next few months.

What is the drain on power when you start adding multiple Z-Wave devices on a mesh network? Has anyone tried to put 100+ in their home?
Unlike powerline carrier systems, X10, Insteon, HomePlug CC, CEBus, and LON Radio Frequency systems like Z-Wave do not suffer from Impedance Loading when additional transmitters are added to a network. In fact, in an RF mesh network the more devices you have the stronger and more fault tolerant your network becomes.

There is a 232-device limit to a single Z-Wave network, however it is not hard to tie multiple networks together using a bridging device if more than 232 nodes are required. This is similar to sub-netting in an IP network. I have seen and installed Z-Wave networks with more than 100 nodes. When establishing a network this large it is helpful, but not required, to use a PC-based controller to configure the network.

Why use 900-MHz range, rather than 2.4 GHz?
Less traffic and better performance. If this question were asked 5 years ago, it would be more valid because wireless telephones took much of the space at the 900-MHz spectrum. However, many of those wireless devices are migrating into the 2.4-GHz space, along with Wi-Fi, video, security cameras, wireless audio, and more. Another important fact is that 900 MHz allows a signal to be stronger and transmit through longer distances (including walls, floors, and ceilings) with more power than a 2.4-GHz signal.

Can I refresh the routing for a device by removing it from the network and re-adding it? Or is there a better way?
If you move a Z-Wave device, it is best practice to remove it from the network and then re-add it in its new location. Some remotes and software also let you “rediscover” the routes to a device, or do so automatically.

I’m looking for a remote fixture module similar to the ZRF113 but smaller. I have an electrical box that measures 3”x3”x1.75”. Currently I have an X10 device in that space. Can you recommend a suitable product?
The plug-in module from Leviton is quite small so it may be possible to use this with a female plug pigtail in your application. Please contact Leviton technical support to see if they would recommend this product in this application.

What significant retail outlet stocks Z-Wave products on its store shelves?
Your best bet is to purchase online, as many of the available products have not made it out to the large national chains yet. You can find Intermatic products at Lowes and Fry’s. Monster products are available in many of the large national consumer electronic stores. ACT and Wayne Dalton products are available online. Leviton products are becoming available through electrical and specialty distributors such as ADI and Worthington. Your best bet is to contact the manufacturer whose products you are interested in and ask them where to find them. Keep your eyes on Z-Wave websites such as Z-Wave.com, Z-Wavealliance.org and ZWaveWorld.com for more information on product availability.

Will the alternate route-seeking feature automatically reroute commands through other neighbor nodes (devices that are members of the same routing table) in order to reach the intended device? For instance in the case that the RF signal for a relaying node is blocked or the relaying node is failed – or does the network need to be rediscovered in order to use an alternate route?
Yes. Z-Wave automatically tries multiple routes if a transmission fails (at any point along its route). Rediscovering the network simply refreshes the available routes. While not necessary for Z-Wave operation, rediscovery can be compared with defragmenting a hard drive. It can get rid of dead links in the system and find new good ones, potentially speeding up your network in the process.

I would like to know what HVAC systems incorporate Z-Wave and who manufactures them?
Right now ACT and RCS have Z-Wave thermostats, Lagotek has a complete multi-zone control solution. We expect several more to become available in the second quarter of 2007.

Does anyone make load control product (commercial/industrial and residential) utilizing Z-Wave?
ACT, Leviton , Monster , Cooper , and Intermatic all have switch products that go up to 15A, some to 20A. Intermatic has 2-pole 30A contactors.

I’m looking for a device that will control my water heater at my country home – something I can turn on and off from my computer. Is there anything designed for larger appliances?
Intermatic has the Contractor Module (Model CA3750) for large loads such as air conditioners, spas, and heaters. The contractor module features a local on/off control and LED feedback. The contact ratings are 30A resistive – 6600 VA, 25A inductive – 5500 VA, 3 Hp @ 220 VAC. NEMA 3R Indoor/Outdoor Case. Agency approval: FCC, CSA c/us. This device could control the power to an electric water heater. You need to make sure that your water heater does not exceed the contact ratings of the device. This is one device that should be installed by a professional. Although it is not yet available, you can pre-order it from www.automatedoutlet.com . Also, in order to control a Z-Wave device remotely, say over the internet, you will need a gateway type product that will serve up a web page for your country home that you can see and change from any computer on the internet, and will also send the Z-Wave commands to the water heater, HVAC, lighting, and security. These gateway products are available from Hawking, Intermatic, Elk, ControlThink, iControl and others.