Danfoss 5000 Flux, Manual

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MG.90.D1.02 – VLT is a registered Danfoss trademark
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VLT ® 5000/5000 Flux/6000 HVAC/8000 AQUA PROFIBUS
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PPO description
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Communication connections
Communication pursuant to PROFIBUS DP, i.e.
EN50170 part 3, is supported when DP is selected
in parameter 800.
Accordingly, a master must be used that supports
PROFIBUS DP.
One of the PPOs described below must be used in
the case of DP communication.
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PPO description (Overview)
A feature of the PROFIBUS profile for variable
speed drives is a communications object designa-
ted 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.
The selection of the PPO type takes place 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 by-
tes). The control word and speed reference value
are transmitted to the VLT in the fixed portion,
whereas the status word and current output fre-
quency are transmitted by the VLT. In the parame-
terizable portion, the user selects which parame-
ters are to be transmitted to the VLT (parameter
915) and which are to be transmitted by the VLT
(parameter 916).
Type 1, 2 and 5 consist of the parameter portion
and 4, 12 and 20 bytes of process data respec-
tively.
Type 3 and 4 consist of 4 and 12 bytes of process
data respectively.
PPO description
PPO, Parameter Process Data Object
PCD Process Data
PCV Parameter Characteristics Value
PCA Parameter Characteristics (bytes 1, 2);
PCA processing see next chapter.
I N D Subindex (byte 3), (byte 4 is not used)
PVA Parameter Value (bytes 5 to 8)
CTW Control Word
STW Status Word
M R V Main Reference Value
MAV Main Actual Value