4.2.4 Process Status Data
Process status data is the process data sent from the
frequency converter and contains information about the
current state.
Slave/master
1
2
3
......
10
STW
MAV
PCD
......
PCD
PCD read
Table 4.5 Process Status Data
PCD 1 contains a 16-bit status word, and each bit contains
information regarding a possible state of the frequency
converter.
PCD 2 contains each default value of the frequency
converter’s current speed in percentage format (see
chapter 4.2.5 Reference Handling
). PCD 2 can be configured
to contain other process signals.
The settings in
parameter 9-16 PCD Read Configuration
define the content of PCD 3–10.
4.2.5 Reference Handling
The reference handling is an advanced mechanism that
sums up references from different sources as shown in
For more information on reference handling, refer to the
frequency converter’s
design guide
.
Illustration 4.2 Reference
The reference or speed setpoint is sent via PROFINET and
is always transmitted to the frequency converter in
percentage format as integers shown in hexadecimal (0–
4000 hex).
The reference (MRV) and feedback (MAV) are always scaled
equally. The setting of
parameter 3-00 Reference Range
determines the scaling of the reference and feedback
(MAV), see
-100%
(C000 hex)
0%
(0 hex)
100%
(4000 hex)
P 3-00 set to
[1] -Max to +Max
P 3-03
Max reference
0
P 3-03
Max reference
0%
(0 hex)
100%
(4000 hex)
P 3-00 set to
[0] Min - Max
P 3-02
Min reference
P 3-03
Max reference
130BA198.10
Illustration 4.3 Reference (MRV) and Feedback (MAV), Scaled
NOTICE
When
parameter 3-00 Reference Range
is set to
[0] Min -
Max
, a negative reference is handled as 0%.
The actual output of the frequency converter is limited by
the speed limit parameters
Motor Low/High Speed Limit
[RPM/Hz]
in
parameter 4-11 Motor Speed Low Limit [RPM]
to
parameter 4-14 Motor Speed High Limit [Hz]
.
The final speed limit is set in
parameter 4-19 Max Output
Frequency
.
lists the reference (MRV) and the feedback (MAV)
formats.
MRV/MAV
Integer in hex
Integer in decimal
100%
4000
16384
75%
3000
12288
50%
2000
8192
25%
1000
4096
0%
0
0
-25%
F000
-4096
-50%
E000
-8192
-75%
D000
-12288
-100%
C000
-16384
Table 4.6 Reference/Feedback (MRV/MAV) Format
NOTICE
Negative numbers are formed as complement of 2.
NOTICE
The data type for MRV and MAV is an N2 16-bit
standardized value, expressing a range from -200% to
+200% (8001 to 7FFF).
Control
PROFINET
12
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