ᐅ Smart Home Building Control Systems / Home Automation / Bus Systems
Created on: 1 Sep 2016 13:15
M
Mycraft
This thread aims to shed some light on the topic...
Because it is becoming increasingly relevant, and the average builder is usually overwhelmed by the many offers, costs, possibilities, pitfalls, and problems involved in construction—especially when it comes to the topic of:
Modern electrical systems in the home during sales discussions. Since I live myself in a house with KNX electrical installation, I will also use examples to take a closer look at the KNX system.
Unfortunately, the term Smart Home is not protected. This results in any house with motion detectors or switchable wireless outlets from discount stores being defined as a Smart Home. It often happens that either only the bare minimum equipment is installed, or the salesperson is so enthusiastic about a certain system that, in the heat of the moment, people install devices that are completely outdated.
However, nothing here is smart... these remain "dumb" add-on components that simply increase comfort temporarily. Why temporarily? Because people are lazy, and eventually it becomes annoying to look for the remote control for the outlets, as it is always in a different place, and because motion detectors cannot be adjusted 100% to the needs of the occupants.
Every builder should become as familiar with their electrical system as with the choice of tiles or other elements of their future home. Too often, people rely on the general contractor (GC) to take care of everything.
If John Doe buys a motor vehicle today, he compares models for days, looks at features, and adds this and that to the wish list. No one wants a car without central locking or electric windows. Still, 20 years ago, it was perfectly normal—and these cars sold like hotcakes. It’s similar with home electrical systems today... you build a house, all options are open, and you could buy extras. But you opt out. Often due to lack of money, but also due to ignorance and entrenched ways of thinking, like “The switch does what it’s supposed to, it turns the light on and off.” What many don’t realize is that much more is possible. People may have heard somewhere that there is something out there, but they are absolutely unsure what, how, and why?
However, over the next 20 years, home electrical systems will likely develop as cars, phones, or televisions have. Nowadays, most people do not want cars without comfort features like central locking, nor phones with cords or CRT TVs.
A modern home electrical system typically looks like this:
The systems are interconnected via wireless or wired networks. They communicate using protocols and operate in the background without needing manual intervention. That means: the blinds automatically lower in strong sunlight to protect the house from excessive solar heat, or the skylight closes when it starts to rain.
Today we have access to a wide range of building automation technology that is available to everyone, unlike just a few decades ago.
We have simple systems with little or no intelligence, such as:
- Conventional electrical installations with push dimmers, impulse relays, etc.
Here, additional comfort is minimal, expandability is practically zero, and almost everything must be operated manually.
Mid-range systems, where many proprietary home automation solutions are found, include:
- Loxone
- Somfy Tahoma
- innogy Smart Home
- HomeMatic
- Philips Hue
- Apple HomeKit
- free@Home
Due to their limited functionality and generally less complex technology—especially regarding installation and programming—these systems tend to be cheaper than comparable building automation systems. The scope of functions and device packages should be carefully reviewed. Proprietary home automation systems are less flexible in terms of features and future expandability compared to building automation systems.
Then, there is the premium class of building automation technology (bus systems):
- LCN
- LON
- WAGO I/O
- Z-Wave
- KNX / EIB
These systems fulfill almost every wish and offer possibilities that many builders only dream of. However, they require thorough planning and are among the most expensive at first glance.
Compared to conventional installations and adding comfort functions in a conventional way, bus systems are becoming increasingly attractive and cost-effective.
Here is a graphic from a major German manufacturer with a presence in all sectors.
The idea behind building automation technology is:
- Integration of as many systems and components as possible (lighting, outlets, heating, ventilation, garden, television, sound system, etc.)
- Monitoring and control of systems from central points
- Expandability and flexibility
- Increase in comfort and ease of use
KNX offers the greatest integration of all systems because it is an open standard. This means the protocol is openly accessible, and all manufacturers who produce and sell KNX products must ensure their products comply with the KNX specifications. In other words, you can use existing experience, but the product must be designed so that it can be operated by any other KNX device from one or several manufacturers. This contrasts with proprietary systems (LOXONE, free@Home, Somfy, etc.), where you are tied to one manufacturer and thus become dependent on them. If production stops and devices in the house break down, you end up with expensive scrap and may have to start from scratch.
KNX is different. There are over 400 manufacturers and millions of products that all “speak” to each other. If a module fails, it is simply removed and replaced by another. It doesn’t matter which manufacturer the new module comes from, as long as it bears the KNX logo. KNX costs money, unfortunately. But as described earlier, the price decreases with the number of functions you want in the house. The debate about whether you need it or not is pointless here. The technology is available, and you have the choice. You can use it or not. As the saying goes: “You can get around by horse carriage too.”
An example:
If you have, for example, 15 roller shutters in the house and want them to be controllable not only locally at the window (without wireless), but also at central points (e.g., at the front door or in the bedroom), and if you want control on each floor, then the initial investment price becomes more reasonable. Because the additional components required for a conventional roller shutter installation (extra switches, separable relays, junction boxes) to provide this functionality are not free, and the labor to wire the shutters accordingly must also be paid for.
Because it is becoming increasingly relevant, and the average builder is usually overwhelmed by the many offers, costs, possibilities, pitfalls, and problems involved in construction—especially when it comes to the topic of:
Modern electrical systems in the home during sales discussions. Since I live myself in a house with KNX electrical installation, I will also use examples to take a closer look at the KNX system.
Unfortunately, the term Smart Home is not protected. This results in any house with motion detectors or switchable wireless outlets from discount stores being defined as a Smart Home. It often happens that either only the bare minimum equipment is installed, or the salesperson is so enthusiastic about a certain system that, in the heat of the moment, people install devices that are completely outdated.
However, nothing here is smart... these remain "dumb" add-on components that simply increase comfort temporarily. Why temporarily? Because people are lazy, and eventually it becomes annoying to look for the remote control for the outlets, as it is always in a different place, and because motion detectors cannot be adjusted 100% to the needs of the occupants.
Every builder should become as familiar with their electrical system as with the choice of tiles or other elements of their future home. Too often, people rely on the general contractor (GC) to take care of everything.
If John Doe buys a motor vehicle today, he compares models for days, looks at features, and adds this and that to the wish list. No one wants a car without central locking or electric windows. Still, 20 years ago, it was perfectly normal—and these cars sold like hotcakes. It’s similar with home electrical systems today... you build a house, all options are open, and you could buy extras. But you opt out. Often due to lack of money, but also due to ignorance and entrenched ways of thinking, like “The switch does what it’s supposed to, it turns the light on and off.” What many don’t realize is that much more is possible. People may have heard somewhere that there is something out there, but they are absolutely unsure what, how, and why?
However, over the next 20 years, home electrical systems will likely develop as cars, phones, or televisions have. Nowadays, most people do not want cars without comfort features like central locking, nor phones with cords or CRT TVs.
A modern home electrical system typically looks like this:
The systems are interconnected via wireless or wired networks. They communicate using protocols and operate in the background without needing manual intervention. That means: the blinds automatically lower in strong sunlight to protect the house from excessive solar heat, or the skylight closes when it starts to rain.
Today we have access to a wide range of building automation technology that is available to everyone, unlike just a few decades ago.
We have simple systems with little or no intelligence, such as:
- Conventional electrical installations with push dimmers, impulse relays, etc.
Here, additional comfort is minimal, expandability is practically zero, and almost everything must be operated manually.
Mid-range systems, where many proprietary home automation solutions are found, include:
- Loxone
- Somfy Tahoma
- innogy Smart Home
- HomeMatic
- Philips Hue
- Apple HomeKit
- free@Home
Due to their limited functionality and generally less complex technology—especially regarding installation and programming—these systems tend to be cheaper than comparable building automation systems. The scope of functions and device packages should be carefully reviewed. Proprietary home automation systems are less flexible in terms of features and future expandability compared to building automation systems.
Then, there is the premium class of building automation technology (bus systems):
- LCN
- LON
- WAGO I/O
- Z-Wave
- KNX / EIB
These systems fulfill almost every wish and offer possibilities that many builders only dream of. However, they require thorough planning and are among the most expensive at first glance.
Compared to conventional installations and adding comfort functions in a conventional way, bus systems are becoming increasingly attractive and cost-effective.
Here is a graphic from a major German manufacturer with a presence in all sectors.
The idea behind building automation technology is:
- Integration of as many systems and components as possible (lighting, outlets, heating, ventilation, garden, television, sound system, etc.)
- Monitoring and control of systems from central points
- Expandability and flexibility
- Increase in comfort and ease of use
KNX offers the greatest integration of all systems because it is an open standard. This means the protocol is openly accessible, and all manufacturers who produce and sell KNX products must ensure their products comply with the KNX specifications. In other words, you can use existing experience, but the product must be designed so that it can be operated by any other KNX device from one or several manufacturers. This contrasts with proprietary systems (LOXONE, free@Home, Somfy, etc.), where you are tied to one manufacturer and thus become dependent on them. If production stops and devices in the house break down, you end up with expensive scrap and may have to start from scratch.
KNX is different. There are over 400 manufacturers and millions of products that all “speak” to each other. If a module fails, it is simply removed and replaced by another. It doesn’t matter which manufacturer the new module comes from, as long as it bears the KNX logo. KNX costs money, unfortunately. But as described earlier, the price decreases with the number of functions you want in the house. The debate about whether you need it or not is pointless here. The technology is available, and you have the choice. You can use it or not. As the saying goes: “You can get around by horse carriage too.”
An example:
If you have, for example, 15 roller shutters in the house and want them to be controllable not only locally at the window (without wireless), but also at central points (e.g., at the front door or in the bedroom), and if you want control on each floor, then the initial investment price becomes more reasonable. Because the additional components required for a conventional roller shutter installation (extra switches, separable relays, junction boxes) to provide this functionality are not free, and the labor to wire the shutters accordingly must also be paid for.
KNX Installation (or another BUS system) versus Conventional Electrical Installation
Requirement: You want a blind or shutter control.
Conventional Blind Control
With a conventional blind control system, the installer will likely mount a wind sensor or even a weather station outside the house. This relatively expensive device’s task is to trigger a wind alert, causing the blinds or shutters to retract, or to lower the blinds when outdoor brightness drops below a certain level. However, all the sensor data collected by the outdoor device is only accessible within the blind control system itself, which functions as a closed system or an isolated island. For example, if you want to use the measured brightness to also automatically switch on the facade lighting, this is not possible. In a conventional electrical setup, the installer would simply install a second brightness sensor for the outdoor lighting—possibly right next to the existing one.
What happens if you want to automate a later-added awning to provide shade when brightness (or temperature) reaches a certain level? Exactly: either this is not possible, or the installer will mount a third sensor on the exterior wall in addition to the other two. Beyond the fact that you pay multiple times for essentially the same sensor data, such setups are neither visually appealing nor easy to maintain, and definitely not flexible.
Blind Control as a BUS Installation
How would this scenario be handled with intelligent building automation? Only a single device (a weather station) is installed on the building. The weather station sends measurement data (brightness, temperature, wind, rain, etc.) as messages over a bus system. Any participant connected to this bus can receive all measurement data and process it as needed. In this case, there could be a shutter actuator controlling the blinds, a switching actuator for the outdoor lighting, and a roller shutter actuator for the awning. And if you want to use the rain sensor data to control garden irrigation, that is also possible.
Control Elements Can Be Smart or Not
This practical scenario can be expanded indefinitely. Let’s look at a simple pushbutton on the wall. In a conventional installation, it might simply raise or lower a blind—nothing more. A KNX pushbutton or a room controller within a KNX system, however, can switch, dim, or operate one or multiple devices—it could be a blind one day, a light or lighting group the next, or the electric door opener or coffee machine another day, or all of these at once. Room controllers with displays can also constantly provide a wealth of useful information and perform complex tasks such as climate control or similar functions.
Here, too, maximum flexibility is achieved: changing the function of the pushbutton happens purely in software. No screwdriver needed, and no local adjustment at the device itself—the change is simply made from the couch.
By contrast, with conventional wiring and retrofit systems that use it, the possibilities are limited and sometimes simply not feasible without significant effort and corresponding costs.
Often, conventional installations are also limited because only one or two rocker switches or 1/2/3 pushbuttons can be installed in a single location, restricting options. The only option is to drill another box if more stationary functions are needed or desired. I have already mentioned switch plates, which often just look poor.
With KNX, you simply assign new functions to the pushbutton and, if needed, replace it with one that has more rockers or buttons. That way, you get the desired functionality in one location.
Requirement: You want a blind or shutter control.
Conventional Blind Control
With a conventional blind control system, the installer will likely mount a wind sensor or even a weather station outside the house. This relatively expensive device’s task is to trigger a wind alert, causing the blinds or shutters to retract, or to lower the blinds when outdoor brightness drops below a certain level. However, all the sensor data collected by the outdoor device is only accessible within the blind control system itself, which functions as a closed system or an isolated island. For example, if you want to use the measured brightness to also automatically switch on the facade lighting, this is not possible. In a conventional electrical setup, the installer would simply install a second brightness sensor for the outdoor lighting—possibly right next to the existing one.
What happens if you want to automate a later-added awning to provide shade when brightness (or temperature) reaches a certain level? Exactly: either this is not possible, or the installer will mount a third sensor on the exterior wall in addition to the other two. Beyond the fact that you pay multiple times for essentially the same sensor data, such setups are neither visually appealing nor easy to maintain, and definitely not flexible.
Blind Control as a BUS Installation
How would this scenario be handled with intelligent building automation? Only a single device (a weather station) is installed on the building. The weather station sends measurement data (brightness, temperature, wind, rain, etc.) as messages over a bus system. Any participant connected to this bus can receive all measurement data and process it as needed. In this case, there could be a shutter actuator controlling the blinds, a switching actuator for the outdoor lighting, and a roller shutter actuator for the awning. And if you want to use the rain sensor data to control garden irrigation, that is also possible.
Control Elements Can Be Smart or Not
This practical scenario can be expanded indefinitely. Let’s look at a simple pushbutton on the wall. In a conventional installation, it might simply raise or lower a blind—nothing more. A KNX pushbutton or a room controller within a KNX system, however, can switch, dim, or operate one or multiple devices—it could be a blind one day, a light or lighting group the next, or the electric door opener or coffee machine another day, or all of these at once. Room controllers with displays can also constantly provide a wealth of useful information and perform complex tasks such as climate control or similar functions.
Here, too, maximum flexibility is achieved: changing the function of the pushbutton happens purely in software. No screwdriver needed, and no local adjustment at the device itself—the change is simply made from the couch.
By contrast, with conventional wiring and retrofit systems that use it, the possibilities are limited and sometimes simply not feasible without significant effort and corresponding costs.
Often, conventional installations are also limited because only one or two rocker switches or 1/2/3 pushbuttons can be installed in a single location, restricting options. The only option is to drill another box if more stationary functions are needed or desired. I have already mentioned switch plates, which often just look poor.
With KNX, you simply assign new functions to the pushbutton and, if needed, replace it with one that has more rockers or buttons. That way, you get the desired functionality in one location.