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Chapter 4
CIP Axis Attributes
412
Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018
These are the motor configuration attributes that apply specifically to rotary
motor types.
PM Motor Rated Torque
Usage
Access
Data Type
Default
Min
Max
Semantics of Values
Optional
Set/GSV
REAL
0
DB
0
N-m
The PM Motor Rated Torque attribute is a float that specifies the nameplate
continuous torque rating of a rotary permanent magnet motor.
PM Motor Torque Constant
Usage
Access
Data Type
Default
Min
Max
Semantics of Values
Optional
Set/SSV*
REAL
0
DB
0
N-m/Amp (RMS)
*
Indicates the attribute cannot be set while the drive power structure is enabled (Power Structure Enable bit in CIP Axis Status is
true).
The PM Motor Torque Constant attribute is a float that specifies the torque
constant of a rotary permanent magnet motor in Newton-meters per RMS Amp.
PM Motor Rotary Voltage Constant
Usage
Access
Data Type
Default
Min
Max
Semantics of Values
Required
Set/SSV*
REAL
0
DB
0
Volts (RMS) / KRPM
*
Indicates the attribute cannot be set while the drive power structure is enabled (Power Structure Enable bit in CIP Axis Status is
true).
The PM Motor Rotary Voltage Constant attribute is a float that specifies the
voltage, or back-EMF, constant of a rotary permanent magnet motor in
phase-to-phase RMS Volts per KRPM.
If the optional PM Motor Torque Constant, Kt, is not explicitly supported in the
implementation the value may be computed from the PM Motor Rotary Voltage
Constant, Ke, according to this equation: Kt (N-m/A
rms
) = 0.01654 * Ke
(V
rms
/Krpm).
PM Motor Rotary Bus Overvoltage Speed
Usage
Access
Data Type
Default
Min
Max
Semantics of Values
Optional - PVT
PM Only
Set/GSV
REAL
0
FD
0
RPM
This value corresponds to the rotary motor speed at which the back-EMF of the
motor equals the maximum operational bus voltage of the drive. When the
Rotary PM Motor Attributes