Two houses off of one M1G?

[apostolakisl]

They do make shielded Cat5 which you can connect to grounding blocks. You could also put surge preventers on the cat 5 terminals. Personally I would put the Cat 5 in sealed conduit. By doing that you can easily pull other data lines if you like. Furthermore, it is not the natural direction of lightening to flow out of the ground and into structures. It can happen, but it is much more common to go the other way.

Your sprinkler must be done with the valves all together sitting right outside your house. Most sprinklers put the valves next to each watering area and run the control wires all around the yard following the main water supply to each zone. I probably have a couple thousand feet of sprinkler wire in my yard. If a voltage spike from lightening got into those wires, it would hop right across the micro air gap in those low voltage relays so I wouldn't put much faith in that.

Every day of our lives we have risk of a million things going wrong. Could lightening cause a surge because of this, I am sure it could. But I would venture to guess your chances of getting in a car accident driving to work are orders of magnitude higher with much worse consequence, and you still do that everyday.

 

[Digger]

Thanks for all the input! Though I don't really understand the concern of ground loops and transients. If nothing is electrically connected between my Elk system and the power wiring of the other house, how does the fact that those components aren't within the same outside walls make any difference? I have a detached garage with underground conduit with wiring for intended expansion of my Elk system. The house next door is actually closer than my garage in the back yard (houses are less than 20' apart). Is the suggestion here that even a detached garage shouldn't be hardwired to the house alarm?!?

As far as the voice announce, my intent was to simply "turn off" voice announcements for the zones over there (but can you disable arm/disarm messages for one area?). Though I'd be interested in hearing about any voice zoning solutions. I agree that a relay/rule kludge probably isn't worth it.

I'm not (yet) concerned with "life alert" type solutions. They aren't that old. This has more to do with the economic events of the past few years than health.

I'm intrigued by the mention of utilizing a wireless bridge. Does this suggest that the Elk communication can somehow be merged into my LAN?

Thanks again for all the input!

If you are within 20 feet then the transients are not as significant of a concern.

For some background on transients you can look here Stedi-Power or elsewhere on the web. The link is mostly for transients on the electrical service entering your house but the concepts are basically the same.

The longer the wire the higher the potential involved. Less than 25 feet you are not at that great of a risk but there is still some. Over 25 feet there is definitely a concern.

 

[electron]

Makes me wonder if something like this wireless RS-485 bridge could work?

 

[Digger]

They do make shielded Cat5 which you can connect to grounding blocks. You could also put surge preventers on the cat 5 terminals. Personally I would put the Cat 5 in sealed conduit. By doing that you can easily pull other data lines if you like. Furthermore, it is not the natural direction of lightening to flow out of the ground and into structures. It can happen, but it is much more common to go the other way.

Your sprinkler must be done with the valves all together sitting right outside your house. Most sprinklers put the valves next to each watering area and run the control wires all around the yard following the main water supply to each zone. I probably have a couple thousand feet of sprinkler wire in my yard. If a voltage spike from lightening got into those wires, it would hop right across the micro air gap in those low voltage relays so I wouldn't put much faith in that.

Every day of our lives we have risk of a million things going wrong. Could lightening cause a surge because of this, I am sure it could. But I would venture to guess your chances of getting in a car accident driving to work are orders of magnitude higher with much worse consequence, and you still do that everyday.

I work for a mfg of alarm systems. Every year we sell several thousand (3 or so) replacement boards (to be honest I was surprised by how many when I saw the numbers). The majority of them are damaged from some sort of surge on either the telco circuit or input/output transients on zones or outputs on the system. Granted these are panels that have been sold for nearly 2 decades in some cases so there are a few million out there.

No matter how well a system is designed a there is no way to protect it from a significant surge not matter who the mfg is.

 

[WayneW]

Makes me wonder if something like this wireless RS-485 bridge could work?

IIRC, Spanky once said that the latency of an RF link would probably not work on the Elk bus. But I don't recall if that was a definite "no" and just a cautious, conservative, safe answer.

 

[gatchel]

Makes me wonder if something like this wireless RS-485 bridge could work?

IIRC, Spanky once said that the latency of an RF link would probably not work on the Elk bus. But I don't recall if that was a definite "no" and just a cautious, conservative, safe answer.

I would stay away from wireless 485. I have tried wireless 485 units on other 485 buss devices at a lower baud rate than the ELk and it doesn't work. I also think spanky confirmed that due to the latency in the conversion or 485 to wireless and back will cause the elk see devices as offline. I will try to find the post.

 

[tmbrown97]

Wayne - I do remember him saying they had tested several options and just not been able to get it to work.

Also E - it looked like that was a one-way device (One was a transmitter, one was a receiver) - and the elk would need 2-way.

I would imagine that if a feasible wireless device came along, Elk would partner with it in a heartbeat. I would so love to be able to add keypads in other parts of the house without having to run wires!

 

[dscline]

The longer the wire the higher the potential involved. Less than 25 feet you are not at that great of a risk but there is still some. Over 25 feet there is definitely a concern.

Thanks, though I'm still struggling with this a bit. Based on your post, I should be concerned about my garage, which is maybe 50' away. Yet according to the Elk literature, the RS-485 bus should not exceed 4000 ft. Obviously, I wouldn't get anywhere near that limit. It seems to me that they would be much more conservative if there were induced transient concerns at such low distances. Based on the discussion, I'm assuming the inference is that the risk is higher outside the confines of my exterior walls? Most of my wiring is in my attic. Is the suggestion that a layer of wood and shingles provides more isolation than buried conduit? Since the RS-485 wiring would be via twisted pairs, wouldn't that significantly reduce the susceptibility of induced currents anyway?

Sorry for all the questions, I'm just trying to understand what the concerns are.

 

[apostolakisl]

The longer the wire the higher the potential involved. Less than 25 feet you are not at that great of a risk but there is still some. Over 25 feet there is definitely a concern.

Thanks, though I'm still struggling with this a bit. Based on your post, I should be concerned about my garage, which is maybe 50' away. Yet according to the Elk literature, the RS-485 bus should not exceed 4000 ft. Obviously, I wouldn't get anywhere near that limit. It seems to me that they would be much more conservative if there were induced transient concerns at such low distances. Based on the discussion, I'm assuming the inference is that the risk is higher outside the confines of my exterior walls? Most of my wiring is in my attic. Is the suggestion that a layer of wood and shingles provides more isolation than buried conduit? Since the RS-485 wiring would be via twisted pairs, wouldn't that significantly reduce the susceptibility of induced currents anyway?

Sorry for all the questions, I'm just trying to understand what the concerns are.

It is a little easier to get to that 4000 ft than you think. When you use the data bus hub, the signal goes out the cat5 and then comes back in the cat 5 to the dbh where it is spliced into the next port on the board. So you are really looking at 2000 ft of wire as the limit. The dbh is doing the daisy chaining for you in essence. This may still be way inside your install. If you have length issues, you can instead daisy chain everything together and this will greatly reduce the feet of wire, but it isn't as clean doing that way and modifications are more difficult.


Put one of these http://cgi.ebay.com/CAT6-CAT5E-CAT5-LIGHTN...=item53df48c92d on your cat5 where it enters the house and you should be reasonably protected. I would also highly recommend one for your telephone line. If you wanted to, you could merge your phone line onto your cat5 and just use one of these. The Elk only uses 4 of the wires on the Cat5 (2 outbound, 2 returning). This won't block a direct hit, but I think your chances of even an indirect hit are very small.

 

[Digger]

The longer the wire the higher the potential involved. Less than 25 feet you are not at that great of a risk but there is still some. Over 25 feet there is definitely a concern.

Thanks, though I'm still struggling with this a bit. Based on your post, I should be concerned about my garage, which is maybe 50' away. Yet according to the Elk literature, the RS-485 bus should not exceed 4000 ft. Obviously, I wouldn't get anywhere near that limit. It seems to me that they would be much more conservative if there were induced transient concerns at such low distances. Based on the discussion, I'm assuming the inference is that the risk is higher outside the confines of my exterior walls? Most of my wiring is in my attic. Is the suggestion that a layer of wood and shingles provides more isolation than buried conduit? Since the RS-485 wiring would be via twisted pairs, wouldn't that significantly reduce the susceptibility of induced currents anyway?

Sorry for all the questions, I'm just trying to understand what the concerns are.

You may want to read this thread More Lightning info

Why not call ELK and ask their tech support about the subject?

FYI UL will do transient tests on any input or output circuit of an alarm system where the wiring leaves the room or goes through any wall or barrier. I beleive that they will soon be changing that to any input or output circuit where the wiring leave the building.

 

[dscline]

It is a little easier to get to that 4000 ft than you think. When you use the data bus hub, the signal goes out the cat5 and then comes back in the cat 5 to the dbh where it is spliced into the next port on the board. So you are really looking at 2000 ft of wire as the limit. The dbh is doing the daisy chaining for you in essence.

Understood. But yes, with my lengths, I would still be way under Elk's limit. I'm just trying to understand the transient concerns. My house isn't that large, so I'm trying to correlate the concerns with my smallish home with "outbuildings" vs. a much larger estate that could actually have longer runs but all inside. I just don't understand the difference, electrically.

If you have length issues, you can instead daisy chain everything together and this will greatly reduce the feet of wire, but it isn't as clean doing that way and modifications are more difficult.

Thanks - I've been assuming I could do this, but the confirmation is good to have. If I were to, for example, have several bus devices in both the garage and other house, it seems silly for the signals for each device to essentially "home run" back to the main panel for each device. Rather, it seems more logical for the signal to go to the garage, daisy-chain through the devices out there, return to the expander at the main panel, then do the same out to the other house. In fact, it would seem to me that I could also put a hubs in the garage and other house, wire them to the "main" hub in the panel in the same fashion that you would daisy-chain hubs together when you need more outlets, and have the benefit of reduced communication length PLUS easy expansion at the remote locations. I would think that a can in each remote location with a hub, a remote power supply+batter, input expander, and output expander, would be like having a separate panel in the remote locations, but with all the logic in the main panel. Of course, the remote power supply would have to be looked at to see if it introduces any additional concerns of ground loops. I would THINK it would be designed with that in mind, considering it's specifically intended for remote power.

Put one of these http://cgi.ebay.com/CAT6-CAT5E-CAT5-LIGHTN...=item53df48c92d on your cat5 where it enters the house and you should be reasonably protected.

Thanks again! Though considering the price, wouldn't I be just as well off with the surge protection built in to many power strips and UPSs? Network jacks are often included on them these days.

 

[apostolakisl]

It is a little easier to get to that 4000 ft than you think. When you use the data bus hub, the signal goes out the cat5 and then comes back in the cat 5 to the dbh where it is spliced into the next port on the board. So you are really looking at 2000 ft of wire as the limit. The dbh is doing the daisy chaining for you in essence.

Understood. But yes, with my lengths, I would still be way under Elk's limit. I'm just trying to understand the transient concerns. My house isn't that large, so I'm trying to correlate the concerns with my smallish home with "outbuildings" vs. a much larger estate that could actually have longer runs but all inside. I just don't understand the difference, electrically.

If you have length issues, you can instead daisy chain everything together and this will greatly reduce the feet of wire, but it isn't as clean doing that way and modifications are more difficult.

Thanks - I've been assuming I could do this, but the confirmation is good to have. If I were to, for example, have several bus devices in both the garage and other house, it seems silly for the signals for each device to essentially "home run" back to the main panel for each device. Rather, it seems more logical for the signal to go to the garage, daisy-chain through the devices out there, return to the expander at the main panel, then do the same out to the other house. In fact, it would seem to me that I could also put a hubs in the garage and other house, wire them to the "main" hub in the panel in the same fashion that you would daisy-chain hubs together when you need more outlets, and have the benefit of reduced communication length PLUS easy expansion at the remote locations. I would think that a can in each remote location with a hub, a remote power supply+batter, input expander, and output expander, would be like having a separate panel in the remote locations, but with all the logic in the main panel. Of course, the remote power supply would have to be looked at to see if it introduces any additional concerns of ground loops. I would THINK it would be designed with that in mind, considering it's specifically intended for remote power.

Put one of these http://cgi.ebay.com/CAT6-CAT5E-CAT5-LIGHTN...=item53df48c92d on your cat5 where it enters the house and you should be reasonably protected.

Thanks again! Though considering the price, wouldn't I be just as well off with the surge protection built in to many power strips and UPSs? Network jacks are often included on them these days.

This can all be done, but it gets a little confusing to jump back and forth between daisy chaining and using the dbh. You really need to keep it straight in your head which wires are taking the signal from where to where. If you are going to stay under your wire limit no probs, I would stick with homerunning everything and using the dbh 100%. Keep in mind that you don't have to have all of your dbh's in the same room. You can connect two dbh's together. In other words, one dbh at your panel, a second dbh in the other house with a single cat 5 between them. Don't forget to terminate the end of line so you don't get reflected signals.


The nice thing about using a surge supressor like I listed is that it can be put on the outside of the house at point of entry preventing the surge from getting into your house at all. These things should protect you very well from high voltage low current surges that could be caused by inductance. High current high voltage is just going to run right through most any surge supressor and just go wherever it wants.

 

[dscline]

Keep in mind that you don't have to have all of your dbh's in the same room. You can connect two dbh's together. In other words, one dbh at your panel, a second dbh in the other house with a single cat 5 between them.

Yes, that is exactly what I was speaking of, probably just not as clearly.

 

[apostolakisl]

This lightening thing seems to be a topic of repeated interest on this board. It is a very ambiguous subject to say the least. It is unlikely to affect you, but if it does it could be a big problem. You want to protect yourself, but have no idea if your protection scheme actually works, you only get notified if it is a failure! It is as if your in school and the teacher only randomly grades one student per month and then only reports that the student was graded if the student failed. There is no way to test it. Even if lightening hits a tree just outside your house, you still don't really know if your stuff was protected by what you did to protect it or if it would have been fine anyway.

I just came across this article http://lightning-protection-institute.com/...ing-protect.htm I found it to be very interesting. The concept of ground potential rise (gpr) is stressed in the article. In just a few paragraphs I feel I have a better understanding of how inductance damages things and how a grounding system can make this type of damage more of a risk if not done properly. I hope others find it interesting.

 

[mdonovan]

Why not call ELK and ask their tech support about the subject?

When I was struggling with my Elk install I wanted to ask them a question. I went to their web site and found this:

ELK Products provides technical support to professional installers only. ELK does not provide technical support directly to consumers. If you are a consumer and have a question about a product manufactured by ELK, please contact either the sales outlet where the equipment was purchased or a professional installer of security equipment.

It's on the M1 Owner Support page after you log in.

Matt