Example 2: Process Data From The Frequency Converter; Stw - Danfoss VLT 5000 Operating Instructions Manual

PCA
PCV IND
PVA
PVA
PCD CTW
MRV
The process data within the PCD portion have a direct
effect on the frequency converter and can be updated
by the master in the quickest possible way.
The PCV portion is a process with an exchange of
acknowledgements (so-called handshake), i.e. the
frequency converter must confirm the command
before a new one can be written.
A positive response of the frequency converter to
the above example might look like this:
PCA
PCV IND
PVA
PVA
PCD

STW

MAV
The response of the PCD portion depends on the status
and the parameterization of the frequency converter.
The PCV portion responds as follows:
PCA
like the request telegram, but with the RC portion
assuming the characteristics for "transmit double
word" (HEX 2 for the RC portion).
IND
is not used in this example.
PVA
03E8Hex in the low-byte of the PVA portion indicates
that the value of the parameter in question (207) is
1000, which corresponds to 10.00. The high-byte
portion of the PVA is HEX 0000.
STW
0F07Hex means that the motor is running and that
no warnings or errors are present (further details
can be found in the status word table).
MAV
2000Hex indicates that the output frequency is
50% of the maximum frequency.
MG.90.G1.02 - VLT is a registered Danfoss trademark
Byte Value
1 and 2 30CF
3 and 4 0000
5 and 6 0000
7 and 8 03E8
9 and 10 047F
11 and 12 2000
Byte Value
1 and 2 20CF
3 and 4 0000
5 and 6 0000
7 and 8 03E8
9 and 10 0F07
11 and 12 2000
VLT® 5000/ 5000 FLUX/ 6000 HVAC/
8000 AQUA PROFIBUS
A negative response of the frequency converter
might look like this:
PCA
PCV IND
PVA
PVA
PCD STW
MAV
RC is HEX 7 which means that the request is not
executable. The corresponding error number is
in the low-byte portion of the PVA.
In this case, the error number 2 means that the upper or
lower warning limit of the parameter has been passed
(see table of error numbers in "PCA processing").
Example 2: Process data from the
frequency converter
Example for filling the variable process data in PPO
4, please see section PPO description.
Assumption: the frequency converter is operating as
in the previous example. At the same time, the motor
current (PCD1), the status of the digital inputs (PCD2),
the frequency value in Hz (PCD3), and the voltage
at terminal 53 (PCD4) are to be indicated.
Fixing the process data on the display unit
The process data from the frequency converter are
read. Therefore, the parameter 916 (PCD-Read) must
be used for the configuration of the PCD.
a. The parameter number for displaying the motor
current is entered on the display unit of the frequency
converter under the index number <1>: 520.
b. The parameter number for displaying the digital
inputs is entered under the index number <2>: 528.
c. Index number <3> = 518 (display of the frequency)
d. Index number <4> = 529 (display of the
voltage at input 53)
Frequency converter response PPO type 4
For example, the frequency converter response
of a PPO 4 telegram after the configuration
might look like this:
STW
PCV MAV
PCD1
PCD2
PCD3
PCD4
Byte Value
1 and 2 70CF
3 and 4 0000
5 and 6 0000
7 and 8 0002
9 and 10 0F07
11 and 12 2000
Byte Value (Hex)
1 and 2 0F07
3 and 4 2000
5 and 6 00F6
7 and 8 0028
9 and 10 00FA
11 and 12 02F8
31