FC101 Design Guide

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 gures are formatted using 2’s
complement. The actual output frequency (MAV) is scaled in the same way as the bus reference.
Actual output
frequency
STW
Follower-slave
Speed referenceCTW
Master-slave
16bit
130BA276.11
Figure 7.17 Actual Output Frequency (MAV)
The reference and MAV are scaled as follows:
Reverse Forward
Par.3-00 set to
(1) -max- +max
Max reference Max reference
Par.3-00 set to
(0) min-max
Max reference
Forward
Min reference
100%
(4000hex)
-100%
(C000hex)
0%
(0hex)
Par.3-03 0 Par.3-03
Par.3-03
(4000hex)(0hex)
0% 100%
Par.3-02
130BA277.10
Figure 7.18 Reference and MAV
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HVAC Basic Drive FC 101
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