Planning an LCN system is easy


Practically every function in a building can be automated using LCN. The LCN system can be extended in many ways and enables manual commands to be linked to automatic functions. This means that a building can be controlled and regulated across all systems. It also effortlessly gives the user the highest level of individual convenience and allows him or her to save money thanks to an optimisation that enables efficient energy consumption.

  • With combinations only few modules needed

  • Only few rules to respect

  • Uncomplicated bus structure

  • Easy to install by an electrician

  • Flexibility with many types of user terminals

  • Extendable up to 30,000 modules

  • No loss of data in huge installations

  • True acknowledgements for commands

  • Flexible in prices and costs

  • High intelligence and functionality

Their “intelligence” means that they can independently send and receive commands, analyse sensors, control actuators and monitor data exchange between modules. A central processor is not needed.

LCN only requires an additional wire in the conventional installation network in order to transmit data. The installer can handle the data cable as he or she usually would as LCN complies with VDE regulations. The installation costs remain very low as no additional wiring system needs to be fitted. Every building – big or small – benefits from this.

Planning an LCN installation is very easy because only few rules must be respected. The maximum number of modules on the lowest level must not exceed 250. In greater installations 250 modules make one segment. Up to 120 segments can be coupled for a maximum number of 30,000 modules. Only in few cases more than 250 modules and several segments are neccesary. Depending on the demands 100 to 200 rooms can be controlled with only 250 modules.

For a very compact installation a single DIN rail module LCN-SH can be combined with a relay block LCN-R8H. This gives ten outputs and the possibility to use up to eight sensor pads, with only one bus module.

Communication between modules

Every LCN module requires an address for it to be responsive. This is a number between 5 and 254 and is issued in seconds by the LCN-PRO. A data telegram can be sent to this address from any point in the entire bus. Group addressing is used if several subscribers need to be contacted with one telegram. 250 group numbers ranging from 5 to 254 can be issued for each LCN bus segment. The number of members of each group is unlimited. Every module can be a member of 12 groups.

In the LCN system, groups are only formed if several loads need to be addressed at the same time. By contrast, modules are addressed directly when using point-to-point transmission (“to module 55: ground floor WC light”); the process is intuitive, as you would expect to be.

More reasons for direct addressing

Besides clarity, there is another important reason for direct addressing: modules can directly send each other information for processing, which creates a “neuronal” network which becomes more and more intelligent and powerful when more and more modules are added to it. This is important for future automation tasks.

Planning examples

The lighting in a room should be regulated using two lighting circuits that can be individually controlled. In so doing, programmable lighting scenes and dimming levels for the respective (dimmable) lighting can be set in the programming. It can be controlled via the LCN-GT6 (see example).
The LCN-GT4D display panel (power fed via the LCN-NUI power supply unit) can also be installed to control heating or other loads.

The temperature within a room should be manually preselected and automatically maintained. In order to do this, the existing actual values are permanently compared with the specified set values. The temperature sensor built into the LCN-GT4D is used to make this comparison. This method allows deviations to be regulated at any time at the corresponding valves via the eight individual controllable relays in the LCN-R8H.

​The shutter motor is directly controlled by a LCN-UMR sensor/actor module. For operation and visual status feedback the LCN-GT4D keypad is used.

The LCN-ULT universal transponder reader is integrated into the bus in order to control a building’s foyer. Up to 16 transponders can be directly analysed in the LCN-UPP module. Doors are opened using a relay switch in the electric door opener. The LCN-GVS is available for more complicated requirements (recognising people, recording, only granting access at certain times of the day).

The temperature within a room should be manually preselected and automatically maintained, but only when the room is in use. If the window is open, the heating must be automatically switched off. After closing the window, it must heat the room back up to the preselected room temperature. If the room is unoccupied for a long period of time, the temperature should be automatically reduced to a low maintenance value. It must also be possible to access all functions manually. A decentrally installed bus module (here: UPP) that is connected to every sensor, the positioner for the heating valve and the keypad required for manual operation is all that is needed for the implementation.

Various temperatures can be preselected via the LCN touch keypad. The current room temperature will then be shown on the display or in the form of a bar graph. Alternatively, EIB/KNX, EnOcean or conventional keypads can be used to operate this system.

A door can be unlocked via a transponder system to allow entry to the building. The lighting in the door area is automatically activated using presence detectors when a person approaches it. A door contact has been installed to protect against misuse of the open door. If the door stays open for a certain amount of time, a security service may be informed via the LCN-GVS visualisation system. The LCN transponder systems enable the use of LCN transponders and/or transponders made by various manufacturers, including those used in car keys.

The LCN-GVS allows the entire LCN system to be remotely controlled using browser-enabled operator devices (smartphones, tablet PCs, notebooks, etc.), in this case to control and monitor the entrance door. The LCN-GVS system also gives you the option of sending SMS messages via the Internet or with a GSM modem via the LCN-GVS system. By using the LCN-GVS app, any number of employees can receive important information as a push notification directly to their smartphone.

Zusätzlich bietet das LCN-GVS System die Möglichkeit SMS-Meldungen per Internet oder mit einem GSM-Modem über das LCN-GVS System zu senden. Bei Verwendung der LCN-GVS APP erhalten beliebig viele Mitarbeiter wichtige Informationen als Push-Nachricht direkt auf ihr Smartphone.

With the LCN-SKO starter kit you can setup a first LCN system and join a one day training. This is the best way to get familiar with the Local Control Network.