Bus Speed Reference Value - Danfoss VLT Compressor Drive CDS 803 Design Manual

RS485 Installation and Set-...

7.11.3 Bus Speed Reference Value

Speed reference value is transmitted to the frequency
converter in a relative value in %. The value is transmitted
in the form of a 16-bit word. The integer value 16384
(4000 hex) corresponds to 100%. Negative figures are
formatted using 2's complement. The actual output
frequency (MAV) is scaled in the same way as the bus
reference.
The reference and MAV are scaled as follows:
7 7
Par.3-00 set to
(1) -max- +max
Par.3-00 set to
(0) min-max
Illustration 7.17 Reference and MAV
68
®
VLT Compressor Drive CDS 803
-100%
(C000hex)
Reverse
Par.3-03
Max reference
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Master-slave
CTW Speed reference
Follower-slave
Actual output
STW
frequency
Illustration 7.16 Actual Output Frequency (MAV)
0%
(0hex)
Forward
0
0%
(0hex)
Forward
Par.3-02
Min reference
16bit
100%
(4000hex)
Par.3-03
Max reference
100%
(4000hex)
Par.3-03
Max reference
MG18N202