Insteon "relay" from device to device (MESH)

[intellihome]

I recently read MarkJames post that is now a "sticky". (Thanks Mark)

 

"The command would get relayed through the network until a responder with a matching destination address received it."

 

I've read a lot of posts over the last year and I thought I read some contradicting information. I can't recall the info, so would rather start fresh to clear my head.

 

As a simple example, My house has 100 devices. I have switchlinc A (controller) linked to switchlinc B (responder),

 

1. Is it true to say that if I press switchlinc A ON, that all 100 devices will relay the command until switchlinc B sends an Acknowledge or the HOP count expires (three tries)?

 

2. What happens when 100 devices try to relay (send the same command all at once)?

 

3. If this MESH network works as described, we should't see so many posts about communication problems??

[upstatemike]

1. yes - although they might not all see it on the first hop, but all that do will repeat it.

 

2. This is where the tightly defined broadcast window comes into play... as long as they are in sync it is not a problem. (Maybe this is what went wrong with v.35 switches?)

 

3. Repeating does not help overcome serious noise or serious signal suckers. If the signal can't be heard over the noise then it can't be repeated. if a sgnal sucker makes it too weak to get very far then it may run out of hop count before reaching its target.

[intellihome]

1. yes - although they might not all see it on the first hop, but all that do will repeat it.

 

2. This is where the tightly defined broadcast window comes into play... as long as they are in sync it is not a problem. (Maybe this is what went wrong with v.35 switches?)

 

3. Repeating does not help overcome serious noise or serious signal suckers. If the signal can't be heard over the noise then it can't be repeated. if a sgnal sucker makes it too weak to get very far then it may run out of hop count before reaching its target.

 

 

Thanks UpstateMike, If I may expand my question a little bit based on your responses...

 

2. What do you mean by in sync? If the signal is received simultaneously by lets say 30 devices (in the same area), how do they start repeating the signal? Who goes first, second, third...? what about the other 70 switches? Are these signals sent parallel? or sequential? wouldn't this cause collisions or be excessive traffic?

 

3. The reason I ask about this is because, prior to insteon, I as well as others had elaborate X10 systems that were quite reliable. I am now 50/50 X10/Insteon. My insteon simply replaced X10 modules. The fact that my X10 worked so well and still does must indicate that I do not have a serious noise or signal sucker problem in my install. I don't want to get off topic with my specific issues but just state that in general, one would assume that the insteon network is not as robust as it is in theory. I read far to many posts on reliability issues where our moderators and members question signal problems due to noise and signal absorption.

As I write this post I start to wonder if certain noise offenders could be more of a problem to Insteon then X10. It's kind of set in my mind that "If it doesn't affect X10 then it won't affect Insteon...maybe that's not true?

[upstatemike]

All devices repeat in parallel in the same time window so the signals do not interfere. In a given time slice (position on the 60Hz sine wave) there will either be a signal or there won't. Does not matter if that signal comes from 1 module or 70 in parallel.

 

X10 modules are usually only receivers so they do not load down the power line and they send much simpler messages.

 

All Insteon modules are both receivers and transmitters so each one lowers the impedance of the power line which impacts signal strength. Also when links are being programmed (not an option with X-1o) there is a fair amount of data being exchanged so more opportunity for a bit to get dropped and the message lost.

[Brian H]

I have found the older receive only Smarthome X10 modules absorb MORE power line signal than a two way Insteon module.

 

Seems they eliminated the tuned transformer in the receiver and substituted a broadly tuned series connected coil and capacitor to the receiver. It seems to be a great signal absorber.

[MarkJames]

Seems they eliminated the tuned transformer in the receiver and substituted a broadly tuned series connected coil and capacitor to the receiver. It seems to be a great signal absorber.

 

Always a handy thing to have in a large X-10 installation.

[intellihome]

All Insteon modules are both receivers and transmitters so each one lowers the impedance of the power line which impacts signal strength.

 

Thanks for elaborating. I did not realize the Insteon signal was more complex and therefore more vulnerable to noise. Makes more sense as to why I have some reliability issues.

 

One last thing...In regards to your quote above, I was under the impression from Smarthome, the more devices you have the stronger more reliable your network. But if the more you have, the more impact you have on signal strength doesn't that make the network weaker?

[upstatemike]

If you do not have any issues on your powerline then having more devices will definitely improve reliability by virtue of the signals being repeated and this should more than compensate for any additional loading.

 

If you have noise, or signal sucker loads then the signal repeating might not be enough to maintain reliability and you might need to use some filters or access points for reliable communications.

 

If things are borderline then simple switch activation might work fine while more complicated activities like adding modules or creating scenes could generate errors.

[IndyMike]

All Insteon modules are both receivers and transmitters so each one lowers the impedance of the power line which impacts signal strength.

 

Thanks for elaborating. I did not realize the Insteon signal was more complex and therefore more vulnerable to noise. Makes more sense as to why I have some reliability issues.

 

Hello Intellihome,

 

Insteon signaling is more complex, but I would not say that it is more vulnerable to noise. Quite the contrary, much of the complexity comes from embedded CRC codes (for error checking) and the command/response/retry functions in the protocol.

 

I believe the complexity that UpstateMike was refferring to was the actual programming of devices. This is complex and lengthy. The same protocol/error detection is used, but since the programming can take minutes and you are effectively writing to many units, there is a greater chance that it will be upset. Nothing like this existed in the X10 world.

 

I also use X10 units alonside my Insteon hardware. Since you appear to be having problems with Insteon units in the same location as your old X10 hardware check for common mode problems:

1) Location of your PLM - If different than your X10 controller, it may be near a noise/absorber

2) Phase coupling - The Accespoints are wonderful little devices that are absolutely required for RF coupling (motion sensors and remotelincs). When used for phase coupling, remember that they can also be affected by local noise/absorbers. For this reason I prefer the X10 method of using a passive coupler at the panel.

3) Presence of V.35 Switchlincs - Michel has indicated that these can cause intermittent failures.

 

IM

[upstatemike]

Yes, the complexity is in programming. Once the links are in place Insteon is always more reliable than X-10. The problem is that you first have to configure the links and if you do that through programming you have more risk of being impacted by power line issues during the process.

 

Folks often unfairly compare the communication they had with simple X-10 on/off commands to the communications problems in Insteon remote programming and claim X-10 was just as good or better, when in reality they are comparing apples to oranges.

[intellihome]

That is in fact where my 98% of my issues arise...programming. The others are KPL buttons as responders.

 

Thanks for the information upstate and Indy Mike. I really appreciate it.