In the context of advertising for Smart Home, the impression is often given that everything works quite simply! Just install the app on my mobile phone or tablet and I can switch the lights and raise or lower the blinds. It’s a nice idea, but a few more steps are necessary to achieve the desired result. In this article, we would like to show what is included in the term smart home and where work is necessary that a specialist should carry out.
What is Smart Home?
Basically, we first have to look at what is meant by the term smart home and where the term comes from. It is a general term that is not associated with any specific company. From Wikipedia: “Smart Home serves as a generic term for technical processes and systems in living spaces and houses […] on the basis of networked and remotely controllable devices and installations as well as automatable processes” (Source: https://de.wikipedia.org/wiki/Smart_Home, accessed on 4.12.2015)
History
In the early 1990s, the term building automation was coined and is still in use today. The main aim here is to no longer operate so-called functional buildings, i.e. office buildings, schools or the like, via individual wall switches or buttons. For example, all lights in the entire building should be switched off after work. Where in the past the caretaker had to walk completely out of the building, the light is automatically switched off. Switching lights is, of course, just one of many possibilities that are possible in building automation. In addition, there are many more, blind control, heating control, ventilation control and much more. The functionality is either implemented in the building itself and works automatically or is additionally provided via so-called visualization software with an extended control function, which is then operated on screens, mobile phones or in the web browser and allows changes to the settings. In this context, we also speak of the system, which means nothing other than the electrical installation including all necessary control and operating units.
Today
Basically, nothing has changed, only the term smart home is new. The term is intended to address the homeowner, who was not the focus of the executing companies just a few years ago, and to emphasize the ease of use via mobile phones or tablets. The expansion to the owner-occupied housing market is made possible by the fact that the supply of homes is almost completely covered by LAN or WLAN, thus providing a basic prerequisite for the use of building technology in the home.
Smart is English for skillful or elegant, it suggests simplicity in use and thus appeals to many people. But is it that simple?
What we see in the various advertisements is nothing more than a visualization of what is going on in the house. Building automation and smart home therefore differ mainly in terms of operability via mobile phone and tablet and the advertising orientation towards use for the home.
The technology behind Smart Home
Devices
In order to be able to automate anything at all in the field of building automation or even the smart home, you need the hardware that is able to take over this automation, the so-called devices, please do not confuse it with smart phones and tablets in this article.
There are different types of devices, sensors, actuators or a mixture of both. The sensor receives information and passes it on, whether by pressing a button or by pressing a rocker switch. The sensor does not execute any commands. An actuator processes this information and an action is taken from the receipt of the data. This can be the simple switching of a light or, more complexly, the activation of a staircase circuit – lights on, wait 5 minutes, lights off. In the area of heating control, far more complex scenarios are conceivable.
The devices are therefore components that can contain both sensor and actuator in switches and buttons. Frequently, however, the sensor and actuator are separated. Actuators, if they are individual devices, are more likely to be housed in the control cabinet. The sensor is usually located in the room as a switch, button or motion detector or outside, for example, as an anemometer or brightness sensor.
Communication
In order for communication between sensors and actuators to take place at all, both must speak the same language. This is regulated by protocols of bus systems. Especially in recent years, many individual solutions have been added here, so that it is impossible to deal with all systems.
The disadvantage of the individual solutions is that they cannot be flexibly expanded. Let’s say a heating thermostat is installed. This is wonderful to operate via a special app. Unfortunately, it is far from guaranteed that another heating thermostat can also be set and operated with the same app.
So if a total solution is expected, it is important that the communication level is uniform and that the devices used can communicate via it. In this case, the specialist knows and can, for example, explain to you in more detail the advantages of the KNX bus – one of the most common solutions.
Multi media connection
For multi media, there is a communication standard that is intended for use in the smart home – DLNA. On players that support this standard, a small sticker is usually attached. If you have devices with this marking, it is usually no problem to control them via an app – provided they are in the same WLAN as the smart phone/tablet and have downloaded the appropriate app. But what if the house’s music library is to be operated via the same app as the lighting and heating? This goes far beyond the requirements of the multi-media app and most smart home apps do not support this requirement either. But there are solutions that can do just that. Namely, to provide communication between the app and various trades such as multi-media, lighting and heating.
Smart Home Apps
Smart Home Apps is a visualization software in the terminology of building automation. Basically, visualization software is the product that displays the states of an installation on a display device – in the smart home sector, this is a smart phone or tablet – and ideally also makes it operable.
But that doesn’t work on its own either. As a minimum requirement, the device and the app must be integrated into the same communication structure (in the simplest case, the WLAN). If communication is not only conducted via the building’s internal WLAN, but also via other communication channels, such as KNX, an additional server is required to support these communications and allow the app to communicate with the corresponding devices.
A system that can be used across all trades and supports many communication systems is the software product Elvis -> www.it-gmbh.de/elvis
Result
Unfortunately, the conversion or initial installation of a building to a smart home is not as easy as it is described in the advertisement. Additional equipment and a communication basis are still required. So if you are really thinking about living in a smart home, you should definitely rely on the knowledge of a specialist.
The expert can determine the exact need with the owner and create a smart home concept. The appropriate system is determined as well as the devices to be used. In this way, the owner can keep an eye on the costs and assess the risks.
