This is a general Z-wave question.
Is there a TTL (time to live) for Z-Wave broadcasts? I assume there is otherwise 2 or more devices could create a loop. The reason I am asking is that I have an out building about 5 or 6 "hops" away from my controller. All of the hops are line of sight, outside, and not more than 30 feet between devices. Yet I frequently have communications issues with the devices in that building. All the devices in the out building work most of the time but not 100%. Often the devices three or more hops away show red exclamations on them. when I click on them it usually says something about basic get.
I have 19 devices in this network and it is fairly robust. There would be multiple paths to the out building.
If there is a TTL can it be edited?
Thanks in advance,
N0VTN
(edited to fix a typo)
Z-Wave Beaming
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- Last Post 07 December 2014
I believe I have just found the answer to my own question.
I Googled "z-wave hops" and found a Wikipedia article about z-wave which states that comands can be relayed up to 4 times.
This explains some of my difficulties. Installing more devices between my buildings may be working against me. Increasing the range of fewer devices looks to be a better approach. A z-wave to ethernet bridge would be ideal but short of buying a pair of Veras (Mi Casa Verde) at close to $200 each I have been unable to find one. I am aware of a Z-wave daughter board for Raspberry Pi, but so far I don't know of any bridges based on these.
Has anyone on this forum attempted to utilize a parabolic reflector behind a z-wave device to increase it's directionality and therfore range?
I have seen some large aluminum lighting relfectors that may work. I will need to measure some of them and plug some numbers into an antenna calculator to see if it might work at 900 MHz. My gut feeling is that they are probably too small to work well at that wavelength.
Coments anyone?
N0VTN
Has anyone on this forum attempted to utilize a parabolic reflector behind a z-wave device to increase it's directionality and therfore range?
I have seen some large aluminum lighting relfectors that may work. I will need to measure some of them and plug some numbers into an antenna calculator to see if it might work at 900 MHz. My gut feeling is that they are probably too small to work well at that wavelength.
If you find a way to increase the range using something like this, I'm interested too.
Perhaps there's a non-zwave approach to this problem; are both buildings on the same local network? Can you tell us more about the problem you are trying to solve?
Both buildings are about 150 feet apart. The outbuilding is within range of my Wi-Fi, I don't currently have a hard line to it but I am not opposed to doing so. The problem is that there are often red exclamations on the more distant devices. The associated messages are either something about basic get or not responding to poling. There are more than enough devices in between, all line of site, and not very far apart. There are also enough devices that there would be more than one path. I suspect that it works when the signals leap-frog other devices. Adding additional devices seems to have diminished performance and caused more communications errors.
I was wondering if there was a maximum number of times a message can be relayed. This seems reasonable to prevent one message from being relayed around forever. Based on what I read on Wikipedia there is a limit of four hops. This could be my problem as there are about 5-6 hops between the buildings. I am thinking about alternative ways to get the Z-wave messages over there. One way would be to increase the range of single hop Z-wave signals, another way would be to implement a bridge to relay Z-wave commands via my computer network.
Local buildings centers (Lowes, Home Depot, Menards etc.) sell inexpensive aluminum utility lights for about $15. One that I looked at last night was 10 inches in diameter. Installing a screw-in lamp module would place the Z-wave transmitter near the focus. I ran the numbers through an antenna calculator and found that at 918 MHz a 10 inch parabolic reflector would give about 5.7 dB of gain. While that isn't a lot of gain, putting one on each end may be enough to provide a reliable single hop of 150 feet. I will have to try this out to see if it works in the real world.
I have two Intermatic HA05 lamp modules to test with but when I look at them with Zen tools it looks like they have a lower data rate than all my other Z-wave devices and I'm not sure that they relay messages, saying beaming=false or something like that. I may be ahead to find a way to rig some other Z-wave device at the center of one of these reflectors.
I don't know of any affordable way to bridge Z-wave over Ethernet. Mi Casa Verde claims to be able to do that but their devices are rather expensive, nearly $200 each and I would need two. I suspect that someone in the Raspberry Pi community will make a bridge but I don't know of one yet and I don't have the software skills to do it myself.
I will update this thread as I research this further.
N0VTN
Might this be some help?
Aeon Labs Repeater
Also, I saw on a couple forum posts elsewhere that the Leviton software has the ability to detect hops? No idea if it might be a help in diagnosing, but here it is (free):
Leviton RF Installer Tool
Would "network heals" help? Smart Route on the device properties?
(Just throwing some ideas out there...)
I am aware of the Aeon Labs Repeater. From what I read it just repeats the signal like any other Z-Wave device, the difference being that it has no other function.
I was anxious to test the Leviton tool, thanks for pointing that out. Unfortunately after installing it, it reports that my Z-stick is not supported, bummer.
The Zen tools has a topology feature that shows which devices every other device can see. This is a useful feature. It would be even better if it reported signal strength, but I suspect the devices don't report those values.
Today I had the opportunity to expiriment with putting a parabolic reflector behind a screw in lamp module to extend the range. I found that without any reflector I was able to get the lamp module to work out to about 175 feet. I then screwed the lamp module into a parabolic aluminum utility lamp holder 10 inches in diameter and aimed it in the directin of my controller. I was able to get the lamp module to operate out to about 300 feet. I did not test with a reflector at each end, as I was out of extension cord and being in the woods I don't have a decent line of sight any farther than that. I hope to test again using a laptop, in a more open environment and on a warmer day. I believe that I was able to achieve these distances because the air is exceptionally dry today.
In the interest of accuracy my test conditions were as follows;
Air tempreature: minus 16 degrees Farenheit
Dew point: minus 24 degrees Farenheit
Wind: officially 9 MPH, however it was pretty calm at ground level in the woods.
It does look like this approach could be useful in helping to better reach an out building.
Next question, has anyone figured out how to set up a static route?
Thanks,
N0VTN
I have wi-fi over powerline in my detached garage, works great with strong local signal in the garage and very decent bandwidth. So I have been wondering if there is a way to send/receive Z-wave communication from the InControl software on my PC to an IP address on my LAN. For example, a Raspberry Pi B+ that is fitting with this Z-Wave daughter card called RaZberry.
It would be amazing if this could be done.
