5 Commissioning and Operation Kübler Group
24 - EN HB Profibus Interface - R67068.0002 - 01
5.3.4 Encoder Start-up Phase on the PROFIBUS
When starting up, the encoder is in the BAUD SEARCH state. After having detected the baud
rate, it switches to the WAIT_PRM state and waits for the parameterizing data from the DP mas-
ter. Parameterizing takes place automatically when the DP master starts.
The following parameters are transmitted to the encoder: Counting direction and measuring
length in steps (for more information, see encoder profile of PNO).
After successful transmission of the correct parameterizing data the encoder switches to the
WAIT_CFG state. The PROFIBUS master sends a configuration byte to determine the number
of inputs/outputs. If the configuration byte is correct, the encoder switches to the DATA_EX-
CHANGE state.
5.3.5 Configuration and Parameterizing
Parameterizing, i. e. the transmission of the parameters for counting direction, encoder resolu-
tion, etc., generally takes place within the configuration program of the used PROFIBUS master.
To this purpose, the type or GSD file (device file) must be copied in the directory for the type or
GSD files. With programs such as COM PROFIBUS or STEP7 Manager, an update of the in-
ternal devices list (hardware catalog) must be performed in the software.
For further information on the integration of field devices, refer to the documentation of the used
software.
Changing the station address
If the station address needs to be changed, the master must support Class 2. This operation is
possible in the start-up phase of the device.
5.3.6 Protective Functions
PROFIBUSDP is provided with many protective functions. They ensure safe and error-free
communication, not only in the harsh environment of the decentralized peripheral devices, but
also in the event of external interferences or failure of one or more participants. Faulty paramet-
erizing is detect directly, since participants with wrong parameters are not integrated in the op-
erating data exchange.
The failure of participants is recorded by the master and displayed for the user with a group dia-
gnostic message. Every failure in the transmission path is detected by the slave by means of
time monitoring and leads to the switching off of the outputs.
EMC interferences are almost filtered out through the differential signal of the interference-safe
RS485 transmission system.
Errors during data transmission are detected by frame and check sum monitoring and lead to
the repetition of the telegram.
5.4 Configuration Parameters Description
5.4.1 Modules
The configuration program generally provides an input mask (display) for the configuration, i. e.
the input of length and I/O type on the PROFIBUS. The identification is already predefined on
this display, independently of the target configuration. Only the I/O addresses must be input.
Depending on the required configuration, the encoder occupies a different number of input and
output words on the PROFIBUS.
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