Limitations of DIY home automation platforms as security systems

Continuing the discussion from Zigbee Device Connectivity Without Repeaters (During a Power Failure):

Here's a new thread to continue discussing the digression from the OP in the thread linked above, the digression that I started :grimacing:.

That is, if anyone still has anything else to say :rofl:.

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@james.fischer May I suggest that instead of Zigbee, for the reasons you stated, you instead consider using the Ring Z-Wave Plus devices with HE for your DIY security system? They are inexpensive, and their Z-Wave Plus repeater has a built-in backup battery.

@bcopeland Has written excellent drivers for the Ring devices on HE.

[Edit] Forgot to mention that Ring drivers are also available from @codahql in addition to an excellent Ring Alarm Unofficial Integration that I use myself.

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I suppose the zigbee protocol does not allow configuration of specific devices, making them sleepy end devices. If there was some control then critical devices could be forced to use a direct connect to the hub where other non critical devices can be left to use the mesh as the protocol sees fit.

I use my system not only for security but also to detect power outages. Problem is if the power detection device is routing through a mains powered repeater the device can't report. The way it is now if the power goes out there is a big hole ripped in the network. I thought every device had multiple paths back to the hub. To my surprise that isn't the case.

I even have a few repeater plugs on a battery backup so it isn't like there is only one way back to the hub.

That's a very interesting point an39511. I should take a look at what "stays connected" and what drops off when the power goes out, to make sure that I don't set off an alarm just because power dropped out. The neighbors would hate me if my house cried wolf when I was several thousand miles away.

Also keep in mind the devices that are sleepy end devices today are not necessarily sleepy end devices tomorrow. The problem I see with zigbee (and possibly zwave) is even though devices can communicate in their mesh network, they do so one path at a time. So if it's regular path is interrupted (power failure) it can take some amount of time before the device re-establishes an alternate path. In my testing I found it can take 30 seconds upwards to 2 minutes before the device connection is restored. And in that time any activity such as open/close events are lost. It is too bad the repeating devices can't repeat for some period of time after mains are lost.

As much as I dislike the idea of WiFi connected devices, at least if the router and hub are on battery those devices can continue to report without interruption.

I am working up a simple battery backup for the Ikea outlets, as they seem the cheapest Zigbee repeater, and the Zigbee card in them is well-documented. Waiting on parts (RIP Radio Shack and Lafayette... we miss you!), but all one needs is a battery holder for a 3 volt battery (CR-2), a diode to keep the battery from being charged by the DC power supply, and a hold-up capacitor something in the 20uF to 200uF range. The diode blocks the positive lead, lets current flow from battery when power fails, the capacitor in parallel with the battery has a charge on it to smooth out the voltage when transmission bursts occur, and during the crucial first moments of a power fail, and that's all she wrote - problem solved for about $3 worst case per Ikea Tradfri. Mount the battery holder on the back side of the protrusion so as to keep the kludge hidden.

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WiFi battery powered contact sensors are not very common, due to the power-hungry nature of WiFi. Perhaps improvements in WiFi technology will improve this over time.

IMHO, if one requires a bullet-proof home security system, then one should buy a dedicated, battery backed up, redundant cellular network, professionally monitored home security system.

If, on the other hand, one has NO current home security system, and would like a low-cost, mostly-reliable, self-monitored home security system, then using a Home Automation hub is an option. Instead of 99.999% up-time like a dedicated, professionally installed and monitored system, it will probably provide ~95%+ up-time.

For many, going from NO Alarm System, to something that is 95%+ reliable is better than nothing, and much more affordable.

Personally, if I lived in a location where I felt an alarm system would be truly beneficial, I would opt either for a professional system OR a very large, grumpy dog. If I lived in a low crime area, I would think adding a little bit of peace of mind from a home automation hub would be better than nothing.

Samsung attempted to industrialize their home automation hub for alarm system duties by partnering with ADT. This required special ADT Contact Sensors, for the same reasons being highlighted by other in this thread. However, we see how well the ST/ADT marriage has gone...with Samsung dropping the product line completely, leaving users of the ADT ST Hub less than thrilled with their purchase. Many Lowes Iris users bought the ADT ST Hub when Iris was shut down, as they relied on Iris as a home security solution. I feel bad for them, as I am sure they have now been very soured by the home automation hub experience...

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And even then, one could argue it might be worse than nothing for some.

Without any security system, one at least knows they need some other plan in place to try to keep themselves or their property safe in a police or life safety emergency.

But if one has a home security solution that was primarily designed to be a home automation system, then there’s a risk of being falsely reassured that the situation will be under control when the time comes.

The difference between ~95% uptime and 99.999% uptime seems small, but there’s a reason most insurance companies will require a certificate that the system meets independent safety testing lab standards before they offer a discount on home insurance premiums.

Insurance companies are pretty good at evaluating risks, otherwise they’d run out of money paying claims.

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Completely agree! A false sense of security can be a very dangerous thing.

We live in a pretty safe area. Every neighbor I know that has installed a professional security system, has ultimately stopped using it for one of two main reasons...

  1. High cost of professional monitoring over time, with little perceived benefit
  2. False alarms leading to a grumpy family, and sometimes annoyed law enforcement

So, in summary... GET A BIG DOG! :wink:

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Agreed, that’s hard to beat, I don’t believe in firearms in the home (there I said it, but let’s not go down that rabbit hole and derail this thread, pretty please :zipper_mouth_face:).

I’ve only been into home automation for a few years. I first looked into ST in 2015 after a minor attempted intrusion incident at our home while we were away on vacation.

My wife wanted some level of door/window monitoring, neither of us really cared about having a traditional security system with central monitoring, and I got a new toy to play with.

It became quickly apparent that if we had actually wanted a security system, even without the benefit of smoke/CO monitoring with fire department dispatch, ST wouldn’t have cut it, and I didn’t see any reason to even bother stepping up to something like Abode, which at least markets itself as more of a security solution.

So I’m content with the convenience notifications that systems like ST or HE can provide. If they also prevent or mitigate the consequences of a crime or fire that occurs in my home, then that’ll obviously be fantastic.

But our primary plans for police and fire/life safety emergencies don’t assume that HE will function as a crucial component.

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Depends on the dog. My grandparents had this German shepherd who believed it was her duty to welcome visitors into the house. Didn't matter who they were. If the fence gate was open, she would lead passers by into the house :joy:

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So true! However, I would hope that most burglars, would happily pass by a house that has a barking dog inside. So much easier to move on to the next house without a dog. :wink:

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It was also in a different era. They lived in a semi-rural community. I think the front door was not only unlocked, it was almost always open during the day. The garden fence was about 4 feet high and the fence gate could be opened from either side ....

I am nostalgic for that simpler time. But addicted to my automated house - what a quandary!

I live in NYC, so a simple deadbolt is 99.99% effective for us. Humans forgetting to lock it is probably its main weakness.

Alas, it’s one of those “jimmy-proof” types that isn’t mortised into the door and frame. I haven’t found a smart lock yet that could easily replace it :disappointed_relieved:.

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I've never felt the need to pay for a dedicated alarm system, especially the ongoing monthly fees. Be that as it may when I started home automation with the SmartThings kick starter I fell in love with the flexibility. I knew enough to have my system on battery and connected via cellular but didn't really understand the whole mesh and how mains powered repeaters could wreck an otherwise great system.

Of course I understand that these HA systems were never designed for home security and that for all other non-security related tasks HA it's great! I just wish there was a way to force critical devices to remain sleepy end devices so when mains are lost critical devices can remain operational. I don't know enough about zwave and zigbee meshes to know if that is even possible but if there is I think it would be a great opportunity for someone to make the platform better and make some money too. Or if there was a repeater that could operate for a short period of time after the mains are lost.

All I know is with all these mains powered repeaters dropping off it really reeks havoc on the mesh and when power is restored it takes a while for everything to settle back down.

Personally I don't want any WiFi home automation devices because its just more unneeded complexity. I'd rather have all zigbee devices if I could. Right now I'm 85% zigbee with the rest being first generation zwave.

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Visonic was one such DIY professional grade system if installed according to standards. (Professional monitoring optional in my mind. ) Rock solid devices , good transmission, good jamming oversight, great battery life, cell connected, etc. Then Tyco bought them and my feeling is the Visonic line was too competitive w/ Tyco's traditional biz that fed a whole food chain. So now you mainly see Visonic in Europe where it was well entrenched. Except for the Xfinity channeled stuff which does not match the same level of quality and design robustness as the old Visonic stuff.

There were lots of things Visonic could have done better and more integrated but it did satisfy the DIY need for pro class failsafe monitoring at a price that was acceptable if you added up the savings from self monitoring.

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Absolutely! I've had a dedicated alarm panel with multi-paths to their remote central station for about 15 years now, mostly for the insurance discount since my "neighbors" are thousands of acres of wooded state/county land in case of a forest fire. The Wink implosion made me look at everything, and I realized that I had built a secondary network of Kidde/Wink smoke detectors that were not connected to remote monitoring. Needless to say, there are three boxes of Ademco/Honeywell wireless detectors in the package decontamination room waiting to be programmed. With Alarm Decoder bridging the Ademco/Honeywell panel into HE, I have all of the benefits of professional remote monitoring with the ability to control the alarm system and use individual alarm system sensors for HA automations. Win-win.....

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You may be the lucky one when your devices are back online after some time. Based on my experience, some devices/repeater does not join back automatically even manually after a reboot in power outage situation. I notice this early on. That is why it is convenience to have battery backed up for your repeater and hub. I would say it is probably necessary after our devices grow to certain number. It is just a hassle to worry about which device come back on line or not after a power outage.

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