Ppo Description; Communication Connections; Ppo Description (Overview) - Danfoss VLT 5000 Operating Instructions Manual

Communication connections

Communication pursuant to PROFIBUS DP , i.e.
EN50170 part 3, is supported.
Accordingly, a master must be used that
supports PROFIBUS DP.

PPO description (Overview)

A feature of the PROFIBUS profile for frequency
converters is a communications object designated as
"PPO", i.e. "parameter process data object".
All cyclical informative data are transmitted via PPOs.
Thus, PPOs form the framework for the data traffic.
One of the PPOs described in the following must be
used in the case of DP communication.
The actual PPO type can be readout in parameter 904.
A PPO may consist of a parameter portion and
a process data portion. The parameter portion
may be used for reading and/or updating of
parameters (successively).
The process data portion consists of a fixed part
(4 bytes) and a parameterizable part (8 or 16
bytes). The Control word and speed reference
value are transmitted to the frequency converter
in the fixed portion, whereas the Status word
and current output frequency are transmitted by
the frequency converter. In the parameterizable
portion, the user selects which parameters are to be
transmitted to the frequency converter (parameter
915) and which are to be transmitted by the
frequency converter (parameter 916).
MG.90.G1.02 - VLT is a registered Danfoss trademark
VLT® 5000/ 5000 FLUX/ 6000 HVAC/
8000 AQUA PROFIBUS
PPO, Parameter Process Data Object
PDC: Process Data
PCV: Parameter-Characteristics-Value
PCA: Parameter-Characteristics (Bytes 1, 2)
PCA handling see section Examples
IND: Subindex (Byte 3)m (Byte 4 is not used)
PVA: Parameter value (Bytes 5 to 8)
CTW: Control
word
See section Examples
STW: Status
word
MRV: Main reference value
MAV: Main actual value (Actual output
frequency)
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