Rockwell Automation SD3000 Drive Configuration, Programming - Manual (Page 85)

Appendix B
SD3000 Local Tunable Variables
Armature and Field Gain Variables
With the exception of armature and field crossover frequency, armature and field current gain variable values
can be generated automatically by using the armature and field ID commands, respectively, in register
100/1100. Crossover frequency for both the armature and the field must be entered by the user if the default
(CURRENT parameter) is not acceptable. The STEP parameter for all the variables is always one (1).
l CML_WCO% - Current Minor Loop Crossover Frequency
Default Current Value: 200
Low Limit: 0
High Limit: 400
Step: 1
The value in this variable selects the desired response of the current minor loop. The units are in radians
per second. The higher the value, the more quickly the drive responds to a change in reference current.
Also note that the higher the value, the less stable the system response becomes.
l ARM CCT% - Armature Threshold Current
Default Current Value: 0
Low Limit: 0
High Limit: 32767
Step: 1
The value in this variable is the armature current at the threshold of continuous conduction. The units are in
amps times 10. For example, a threshold current of 1 Amp would be entered as a value of 10. This value
can be generated automatically by commanding the armature ID test in register 100/1 100.
l ARM R% - Armature Resistance
Default Current Value: 0
Low Limit: 0
High Limit:
32767
Step: 1
The value in this variable is the resistance of the armature when it is in continuous conduction. The value is
displayed ohms x 100. For example, an armature resistance of 1 ohm would be entered as a value of 1000.
This value can be generated automatically by commanding the armature ID test in register 100/1 100.
I
l ARM TE% - Armature Electrical Time Constant
Default Current Value: 0
Low Limit: 0
High Limit: 5000
Step: 1
The value in this variable is the electric time constant of the motor. It is scaled in milliseconds times 10 so
that a time constant of (Te) of 10 milliseconds has a value of 100. The largest value that can be stored in
this variable is 0.5 seconds. This value can be generated automatically by commanding the armature ID
test in register 100/1 100. The ID test will provide a time constant value that takes into account the entire
circuit providing power to the motor, and may be different from the time constant provided by the
manufacturer on the motor nameplate.
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