December 5, 2012 at 11:55“Leaving, extinguish everything.” The principle of building a partially disconnected apartment electrical network is one of the stages of preparation for the creation of a “smart home”
Increasingly, I come across articles from the "builders of smart homes", which in an already finished house or apartment create some kind of automation, as a rule, relating only to lighting. At the same time, since the repair has been done a long time ago, all kinds of workarounds with excessive complexity are used - wireless technologies with a bunch of transceivers, perverts on the use of free conductors of laid low-current wiring and the like crutches. And on the mezzanines, behind cabinets and under sofas, bundles of boards and wires or, in the best case, separate wiring boxes are formed.
In my opinion, all this is not serious, not thorough, not reliable, unnecessarily complicated and not durable. In a word - the layout. The right smart home, in my opinion, needs to be created from scratch, from the project, and even at the stage of construction or overhaul, lay all the necessary communications and actuators.
In this article I will describe one of the aspects of the “foundation” of a smart home - the option of wiring power wiring, which I implemented in my apartment during the overhaul. The ultimate goal I did not set myself to create a full-fledged smart home, for me it was important to solve the only problem - when leaving home, centrally turn off all lighting, all unnecessary power consumers and block the entry of hot and cold water.In my case, this is done by manually pressing a special key, but the control can be easily integrated into the automation of a full-fledged smart home.
I do not consider myself paranoid, who, leaving the house, without fail turn off all electrical appliances, remove all plugs from outlets, unscrew light bulbs and do such stupid things. However, if no one is left in the apartment, before leaving, it is nevertheless necessary to check all sorts of irons, soldering irons, ovens, and the light will be extinguished everywhere. And at the same time it would be nice to check whether the water is closed everywhere.
But doing this every time is laziness, and you can forget it, especially if you are in a hurry or your head is busy with something. I want it to be done at least centrally and quickly, in one motion, at most automatically. Next, I will describe how I solved the minimum problem.
The main idea is that the entire power grid is divided into two subnets. One of the subnets operates continuously, the other can be centrally de-energized by one contactor. When designing the power grid, you need to divide all possible consumers in the house into two groups. The first group is all the lighting and consumers, which should be turned off if no one is at home. The second group is consumers, who must work in the absence of owners.
Then it is necessary to plan the location of the power points of all electrical consumers, and design the power grid so that the power of the devices of the first and second groups is not interconnected up to the main switchboard.
Of course, it is difficult to take everything into account in a project at once. And over time, the conditions for using household electrical appliances can change. Therefore, I made a compromise - I placed the power points (sockets or junction boxes) in the most likely places for connecting devices so that each room had at least two sockets for devices of a smaller number of the second group (continuously powered), spaced on different walls. I do not welcome the use of tees and extension cords in constant mode, so I still broke my brain over what specifically and where I might need to connect, so that at least for the first time I did not have to branch out the power supply. But if in the future it will still be needed, first of all I will think about how to install an extra outlet, and not stick a tee.
Those outlets that are connected to the second subnet (continuous power) must be marked or highlighted somehow differently so as not to be confused with the first subnet. When using outlets, you need to monitor which subnet we connect the consumer to. There shouldn’t be any particular inconvenience - continuous power outlets can be located in less accessible places directly next to the intended consumers and in much smaller quantities. And plug-in sockets in convenient, easily accessible places.
At the moment, I have not yet figured out how to simply and reliably implement the automatic shutdown of the first subnet when leaving the apartment of all people. Now I carry out the control manually with a key specially brought out to the front door. At first, I was afraid that there would be problems with forgetting to do it. But no, pressing a key became a habit for everyone very quickly. However, the idea of automating this process has not yet left. But how to determine that there are no people in the apartment - I do not know yet. In addition to motion sensors, nothing comes to mind, but I do not really trust them. I would be glad if in the comments I see any thoughts about this.
As always, in seemingly simple systems, unforeseen complications arise. In my household, two powerful electrical appliances were discovered, which created a certain problem. This is an electric oven and microwave. On the one hand, these devices should not work in the absence of people and must be de-energized. On the other hand, they have a built-in clock, which requires continuous power supply. It would be possible to solve the problem by buying a battery-powered LCD clock in the kitchen. But the reset clock on the oven annoyingly and continuously flashes zeros, and in addition, until the clock is set, the oven refuses to work at all - does not even allow itself to be turned on. I don't somehow smile at the clock every time I get home.
The solution to this contradiction came in the form of organizing a third subnet, which is not completely turned off, but is transferred to a more low-current protection circuit breaker. This subnet in the shield is protected by two machines, connected in series - powerful and low-current. In my case it is 16A and 1A. In active mode, when all subnets are turned on, the 1A circuit breaker is not used (shorted by the contactor) and this third subnet is protected only by the 16A circuit breaker. In sleep mode, when the first subnet is turned off, the 1A circuit breaker is turned on, which becomes the weakest link in the third subnet and allows the clock to work in powerful devices, but immediately turns off if these powerful consumers were not turned off due to forgetfulness or turned on by timer in lack of people.
Another unpleasant moment was the constantly humming main contactor in the electrical panel in the hallway, which disconnects the first subnet. But, to my surprise, a special silent contactor was found in the Legrand catalog, which I eventually installed, the buzz disappeared.
Not being paranoid in the field of electrical safety, I am very wary of possible leaks in the water supply system when there is nobody at home (well, everyone has their own cockroaches). But shutting off valves on risers every time is again laziness. Therefore, even before the repair began, I decided to install a leakage protection system with motorized ball valves. Such a system was installed, but still does not cause full confidence, although I test it periodically and while everything works properly.
And I decided to connect the control of motorized electric screens to the shutdown control of the first subnet, so that when leaving the house, the water supply would automatically shut off. At the same time, without disturbing the regular operation of the leakage protection system. Another small complication arose here - I wanted the cranes to be powered from the first subnet and to be de-energized after closing, but it takes some time (about 10 seconds) to close them, so the first subnet cannot be de-energized immediately by pressing a key or by applying the corresponding commands from automation. I had to install a time delay relay in the dashboard. Now, after pressing the shutdown key of the first subnet, the taps are closed first, and then, after 10 seconds, the power is removed from the subnet.
This time relay introduced an additional feature into the control logic - the ability to cancel the shutdown within 10 seconds :) That is, if you pressed the button accidentally, or suddenly changed your mind about leaving the house, you can return the button to its original position, the subnet will not turn off, and the taps will open. Conveniently, I have repeatedly resorted to this opportunity.
The whole system of the partially disconnected power supply has been working properly for four years, confirming its reliability and fully justifying the cost of its implementation with ease of use.
I wanted to draw a diagram for clarity, but decided that the components I use are quite individual, so the diagram will be too specific and of little use for a larger number of readers. The main thing is the general principle of building a power grid. And there may be many options.
In my opinion, all this is not serious, not thorough, not reliable, unnecessarily complicated and not durable. In a word - the layout. The right smart home, in my opinion, needs to be created from scratch, from the project, and even at the stage of construction or overhaul, lay all the necessary communications and actuators.
In this article I will describe one of the aspects of the “foundation” of a smart home - the option of wiring power wiring, which I implemented in my apartment during the overhaul. The ultimate goal I did not set myself to create a full-fledged smart home, for me it was important to solve the only problem - when leaving home, centrally turn off all lighting, all unnecessary power consumers and block the entry of hot and cold water.In my case, this is done by manually pressing a special key, but the control can be easily integrated into the automation of a full-fledged smart home.
I do not consider myself paranoid, who, leaving the house, without fail turn off all electrical appliances, remove all plugs from outlets, unscrew light bulbs and do such stupid things. However, if no one is left in the apartment, before leaving, it is nevertheless necessary to check all sorts of irons, soldering irons, ovens, and the light will be extinguished everywhere. And at the same time it would be nice to check whether the water is closed everywhere.
But doing this every time is laziness, and you can forget it, especially if you are in a hurry or your head is busy with something. I want it to be done at least centrally and quickly, in one motion, at most automatically. Next, I will describe how I solved the minimum problem.
Idea
The main idea is that the entire power grid is divided into two subnets. One of the subnets operates continuously, the other can be centrally de-energized by one contactor. When designing the power grid, you need to divide all possible consumers in the house into two groups. The first group is all the lighting and consumers, which should be turned off if no one is at home. The second group is consumers, who must work in the absence of owners.
Then it is necessary to plan the location of the power points of all electrical consumers, and design the power grid so that the power of the devices of the first and second groups is not interconnected up to the main switchboard.
Of course, it is difficult to take everything into account in a project at once. And over time, the conditions for using household electrical appliances can change. Therefore, I made a compromise - I placed the power points (sockets or junction boxes) in the most likely places for connecting devices so that each room had at least two sockets for devices of a smaller number of the second group (continuously powered), spaced on different walls. I do not welcome the use of tees and extension cords in constant mode, so I still broke my brain over what specifically and where I might need to connect, so that at least for the first time I did not have to branch out the power supply. But if in the future it will still be needed, first of all I will think about how to install an extra outlet, and not stick a tee.
Those outlets that are connected to the second subnet (continuous power) must be marked or highlighted somehow differently so as not to be confused with the first subnet. When using outlets, you need to monitor which subnet we connect the consumer to. There shouldn’t be any particular inconvenience - continuous power outlets can be located in less accessible places directly next to the intended consumers and in much smaller quantities. And plug-in sockets in convenient, easily accessible places.
At the moment, I have not yet figured out how to simply and reliably implement the automatic shutdown of the first subnet when leaving the apartment of all people. Now I carry out the control manually with a key specially brought out to the front door. At first, I was afraid that there would be problems with forgetting to do it. But no, pressing a key became a habit for everyone very quickly. However, the idea of automating this process has not yet left. But how to determine that there are no people in the apartment - I do not know yet. In addition to motion sensors, nothing comes to mind, but I do not really trust them. I would be glad if in the comments I see any thoughts about this.
Underwater rocks
As always, in seemingly simple systems, unforeseen complications arise. In my household, two powerful electrical appliances were discovered, which created a certain problem. This is an electric oven and microwave. On the one hand, these devices should not work in the absence of people and must be de-energized. On the other hand, they have a built-in clock, which requires continuous power supply. It would be possible to solve the problem by buying a battery-powered LCD clock in the kitchen. But the reset clock on the oven annoyingly and continuously flashes zeros, and in addition, until the clock is set, the oven refuses to work at all - does not even allow itself to be turned on. I don't somehow smile at the clock every time I get home.
The solution to this contradiction came in the form of organizing a third subnet, which is not completely turned off, but is transferred to a more low-current protection circuit breaker. This subnet in the shield is protected by two machines, connected in series - powerful and low-current. In my case it is 16A and 1A. In active mode, when all subnets are turned on, the 1A circuit breaker is not used (shorted by the contactor) and this third subnet is protected only by the 16A circuit breaker. In sleep mode, when the first subnet is turned off, the 1A circuit breaker is turned on, which becomes the weakest link in the third subnet and allows the clock to work in powerful devices, but immediately turns off if these powerful consumers were not turned off due to forgetfulness or turned on by timer in lack of people.
Another unpleasant moment was the constantly humming main contactor in the electrical panel in the hallway, which disconnects the first subnet. But, to my surprise, a special silent contactor was found in the Legrand catalog, which I eventually installed, the buzz disappeared.
Additional functions
Not being paranoid in the field of electrical safety, I am very wary of possible leaks in the water supply system when there is nobody at home (well, everyone has their own cockroaches). But shutting off valves on risers every time is again laziness. Therefore, even before the repair began, I decided to install a leakage protection system with motorized ball valves. Such a system was installed, but still does not cause full confidence, although I test it periodically and while everything works properly.
And I decided to connect the control of motorized electric screens to the shutdown control of the first subnet, so that when leaving the house, the water supply would automatically shut off. At the same time, without disturbing the regular operation of the leakage protection system. Another small complication arose here - I wanted the cranes to be powered from the first subnet and to be de-energized after closing, but it takes some time (about 10 seconds) to close them, so the first subnet cannot be de-energized immediately by pressing a key or by applying the corresponding commands from automation. I had to install a time delay relay in the dashboard. Now, after pressing the shutdown key of the first subnet, the taps are closed first, and then, after 10 seconds, the power is removed from the subnet.
This time relay introduced an additional feature into the control logic - the ability to cancel the shutdown within 10 seconds :) That is, if you pressed the button accidentally, or suddenly changed your mind about leaving the house, you can return the button to its original position, the subnet will not turn off, and the taps will open. Conveniently, I have repeatedly resorted to this opportunity.
The whole system of the partially disconnected power supply has been working properly for four years, confirming its reliability and fully justifying the cost of its implementation with ease of use.
I wanted to draw a diagram for clarity, but decided that the components I use are quite individual, so the diagram will be too specific and of little use for a larger number of readers. The main thing is the general principle of building a power grid. And there may be many options.