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3. Fieldbus Interface
3.1. Fieldbus Interface
3.1.1. Introduction
This section is only relevant if the frequency converter is equipped with a Fieldbus
interface (option) as well as the Positioning controller.
The Positioning controller can be controlled via the digital/analogue inputs or via fieldbus. The
control source can be selected in parameter 19-04. There can only be one control source at a time
meaning that the digital/analogue inputs are inactive when fieldbus is selected as control source
and visa versa. The only exceptions are listed in the digital interface section. In fieldbus mode it
is possible to specify only the target position and velocity. If the acceleration and deceleration
PCDs are left blank then the last used acceleration and deceleration chosen via a quickbus is used.
This enables the use of PPO type 4.
3.1.2. Data Layout
Control and status signals are transferred via the so-called process data channel (PCD) of the
various fieldbus interfaces. The telegram structure and the available number of data words de-
pends on the fieldbus used, please refer to the manual of the fieldbus option in use for further
details. The below example is based on the layout of a PROFIBUS telegram, the so-called PPO:
Example using PROFIBUS PPO type 5:
MCO351 Positioning Controller
3. Fieldbus Interface
MG.33.R1.02 - VLT
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