ABB ACS850 series, Руководство пользователя

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334 Control through the embedded fieldbus interface
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References for the DCU 32-bit profile
The DCU 32-bit profile supports the use of two fieldbus references, REF1 and REF2.
The references are 32-bit values consisting of two 16-bit words. The MSW (Most
significant word) is the integer part and the LSW (Least significant word) the fractional
part of the value. A negative reference is formed by calculating the two’s complement
from the corresponding positive value of the integer part (MSW).
The fieldbus references are written as is into the drive reference values ( 02.38 EFB
main ref1 or 02.39 EFB main ref2 ). Parameters 50.04 Fb ref1 modesel and 50.05 Fb
ref2 modesel define the reference types (speed or torque) as follows:
• If you select value Raw data , the fieldbus reference type or possible use is not
selected. The value is freely usable as a speed or torque reference in the drive.
• If you select value Speed , the fieldbus reference can be used as a speed
reference in the drive.
• If you select value Torque , the fieldbus reference can be used as a torque
reference in the drive.
The table below clarifies the relation between the fieldbus reference and drive
reference (no scaling).
1)
If the reference value is used as the speed reference, it will be the motor speed in rpm. If the reference
value is used as the torque reference, it will be the motor torque in percent of the motor nominal torque.
Fieldbus reference REF1 or REF2
[integer and fractional part]
Corresponding reference
in the drive [rpm or %]
1)
32767.65535 32767.65535
0 0
-32768.65535 -32768.65535