NOTE!
If you use long motor cables (max. 100 m) with small drives (≤1.5 kW), the motor
current that the drive measures can be much higher than the actual motor current.
It is because there are capacitive currents in the motor cable.
8.7
FIELDBUS CONTROL PARAMETERS (IDS 850 TO 859)
The Fieldbus control parameters are used when the frequency or the speed reference comes
from the fieldbus (Modbus, Profibus, DeviceNet etc.). With the Fieldbus Data Out Selection
1-8 you can monitor values from the fieldbus.
8.7.1
PROCESS DATA OUT (SLAVE -> MASTER)
The fieldbus master can read the AC drive’s actual values using process data variables.
Basic, Standard, Local/Remote, Multi-Step, PID control and Pump and fan control
applications use process data as follows:
Table 210: The default values for Process Data Out in fieldbus
Data
Default value
Unit
Scale
ID
Process Data Out 1
Output frequency
Hz
0.01 Hz
1
Process Data Out 2
Motor speed
rpm
1 rpm
2
Process Data Out 3
Motor current
A
0.1 A
45
Process Data Out 4
Motor torque
%
0.1%
4
Process Data Out 5
Motor power
%
0.1%
5
Process Data Out 6
Motor voltage
V
0.1 V
6
Process Data Out 7
DC link voltage
V
1 V
7
Process Data Out 8
Active fault code
-
-
37
The Multipurpose application has a selector parameter for every Process Data. The
monitoring values and drive parameters can be selected using the ID number. Default
selections are as in the table above.
8.7.2
CURRENT SCALING IN DIFFERENT SIZE OF UNITS
NOTE!
Monitoring value ID45 (usually in Process data OUT3) is given with one decimal
only.
PARAMETER DESCRIPTIONS
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