KM200 Binding

The KM200 Binding is communicating with a Buderus Logamatic web KM200 / KM100 / KM50. It is possible to receive and send parameters like string or float values.

Important: If the communication is not working and you see in the logfile errors like “illegal key size” then you have to change the Java Cryptography Extension to the Unlimited Strength Jurisdiction.

Binding Configuration

This binding can be configured in the file services/km200.cfg.

Property Default Required Description
ip4_address   Yes IP address of KN200 to connect to
PrivKey   No a complete private key, for example 0000FFFFEEEEDDDDCCCCBBBBAAAA999988887777666655554444333322221111. If you do not have one, use the following three configuration properties
MD5Salt   if you do not have PrivKey the md5salt value, for example 111122223333444455556666777788889999aaaabbbbccccddddeeeeffff0000
GatewayPassword   if you do not have PrivKey the device password, for example AAAABBBBCCCCDDDD
PrivatePassword   if you do not have PrivKey the private password, for example MYPASSWORD

Item Configuration

There are two different ways to configure the items.

1. Direct access with defined key

DateTime  budDate	"Buderus Date Time [%1$tA, %1$td.%1$tm.%1$tY]" {km200="date_time"}
DateTime  budDate	"Buderus Datum [%1$td.%1$tm.%1$tY %1$tH:%1$tM]" {km200="date_time"}
String  budBrand "Brand of the heater [%s]" {km200="sys_brand"}
String  budType "Type of the heater [%s]" {km200="sys_type"}
String  budStatus "State of the heater [%s]" {km200="sys_state"}
String  budFirmware "Firmwareversion [%s]" {km200="ver_firmware"}
String  budHardware  "Hardwareversion [%s]" {km200="ver_hardware"}

2. List of avalible services

The second way is the definition of user-defined items with direct path to the services. Here you need to know which kind of services is your device supports. This information you will get from this binding.

  • Put the correct configuration in the services/km200.cfg file.
  • Now you have to start openHAB and take a look in the openhab.log file.
  • Here you will see after one or two minutes after start, a table with all supported services and capabilities. It looks like this:

You can copy this table in a spreadsheet like Microsoft Excel. It is ‘;’ seperated.

The colums are:

Property Description
readable Service is readable, if not then you cannot use it
writable It is possible to set values
recordable It is possible to create recordings. Not directly supported yet
virtual This service is only virtual and not existing of the device. The binding is translating the message to the parent
type FloatValue, stringValue, switchProgram (not supported), refEnum ( not relevant), yRecording (not supported)
service This is the path for the configuration
value Value of the service in the time of the init
allowed If existing then only this values are possible
min The min value for a float
max The max value for a float

You can select this services in the config with the syntax: service: <fullPathToService>

Switching Programs

The binding now supports the reading and changing of switching programs.

The communication between the binding and the user is done over virtual services. In the service list are now virtual services included. Every switch program service has now five virtual subservices. They are:

Subservice Description
weekday Selection of a weekday, possible: Mo/Tu/We/Th/Fr/Sa/Su
nbrCycles The number of cycles (on+off or day+night, depends on the parent service) on the selected day
cycle Selection of a cycle on the selected day
on/day The selected switch time for the on/day type of the selected cycle
off/night The selected switch time for the off/night type of the selected cycle

Add a new switch cycle

With the last commit it’s possible to add a switch cycle to the end of the cycle list.

  • Set a weekday.
  • Set the cycle to the one after the number of actual cycles.
  • Set the time for the new on/day type, it will by automaticly moved to the first possible time.
  • Set the time for the new off/night type, it will by automaticly moved to the first possible time.

Remove a switch cycle

With the last commit it’s possible to remove a switch cycle from the end of the cycle list.

  • Set a weekday.
  • Set the cycle to the last one.
  • Set the time for the off/night type to max time (1430 Minutes).
  • Set the time for the on/day type to max time (1430 Minutes).
  • Some seconds later it will be removed.

##Error Lists

The binding supports the parsing of the device error list. This list is usally readable from the /notification service.

This has now new subservices:

Subservice Description
nbrErrors The number of errors
error Selection of the error for generation of the errorString
errorString String with all informations about this error

Dynamic service path (Parameter replacement)

In some cases the path to the service not static. It depends on something else like another service. One example for this are switching programs. It is nice to see switch points parameters from the current selected program.

This binding is supporting parameter replacements. It meens that’s possible to replace a part of the service path with a values from another service.

Parameter Replacement
__current__ current:<path>


String  budState "State of the heating [%s]"  {km200="service:/system/healthStatus"}
Number	budTemp  "Temperature heating night [%.1f °C]" {km200="service:/heatingCircuits/hc3/temperatureLevels/night"}

For switches, you can define which of the allowed values is the one for ‘on’ and ‘off’.

Switch  budMode  "Mode [%s]" { km200="service:/heatingCircuits/hc3/operationMode on:auto off:night" }

Switching programs: (you have to select as first the day, second the cycle and then read/write on/day or off/night).

String actBudDayHC1 "Day HC1 [%s]" {km200="service:/heatingCircuits/hc1/switchPrograms/Eigen1/weekday" }/Number nbrBudNbrCyclesHC1 "Cycles HC1 [%d]" {km200="service:/heatingCircuits/hc1/switchPrograms/Eigen1/nbrCycles" }/Number actBudCycleHC1 "Selected cycle HC1 [%d]" {km200="service:/heatingCircuits/hc1/switchPrograms/Eigen1/cycle" }/Number actBudPosHC1 "Day  HC1  [%d]" {km200="service:/heatingCircuits/hc1/switchPrograms/Eigen1/day" }/Number actBudNegHC1"Night HC1  [%d]" {km200="service:/heatingCircuits/hc1/switchPrograms/Eigen1/night" }/
Number nbrBudNbrCyclesHCT1Curr "Current HC1 [%d]" {km200="service:/heatingCircuits/hc1/switchPrograms/__current__/nbrCycles current:/heatingCircuits/hc1/actualSwitchingProgram" 

Example files (in German)





KM200 Binding with OpenHAB

KM200 Binding with CometVisu

Supported item types

Item Type KM200 service type
Number For string, float and switching program (cycle, nbrCycles, on/day, off/night)
String For string, float and switching program (weekday))
DateTime For string and switching program (on/day, off/night)
Switch For string

This binding is automaticly blocking the values to the allowed and limiting them to the min and max capabilities.