The problem with my first installation was different software
1. HomeMatic Configurator (recognizing and configuring devices)
2. HomeMatic LAN interface Configurator (utility for fixed IP and AES LAN encryption)
So Config software running default is DHCP and it gets the serial number and the AES Key queried, input and it runs.
Needs to subsequently use the LAN adapter with FHEM to the AES-LAN encryption disable this happens on the utility (fixed IP, AES LAN encryption), then I could not configure more device in the status bar was always displayed no connection to LAN adapter.
The solution: one issued by the utility "HomeMatic LAN interface Configurator" the AES Encryption, so must be entered in the field of Home Automatic configuration software no "access code". If you would only use a software configuration so you could adjust the this error can not occur.
Otherwise, the device is working properly.