Rockwell Automation 1398-DDM-xxx USE MNL/ULTRA 200 DIG.SERVO.DR - Manual (Page 270)

Publication 1398-5.0 – October 1998
D-6 Creating Custom Motor Files
Synchronous/Induction
This field identifies whether the motor is a synchronous (permanent
magnet) motor or an induction motor. The motor type informs
ULTRA Master which fields are valid for a particular motor, and
which fields are invalid (grayed).
These instructions only cover permanent magnet motors, so the
Synchronous box must be checked.
Number of Poles
The number of poles specifies the number of electrical cycles in two
mechanical revolutions. For example, a 6-pole motor will have three
electrical cycles per mechanical cycle. The firmware can support only
2-, 4-, 6-, and 8-pole motors.
Occasionally a manufacturer specifies the number of pole pairs in a
motor data sheet. Pole pairs should not be confused with the number
of poles. A 6-pole motor has 3 pole pairs.
K
T
(Torque Constant)
The torque constant, also known as the torque sensitivity, specifies the
amount of torque that the motor can produce with a given value of
sinusoidal current. The torque constant is measured in units of N-m/
Amp, and its range is 0.0002 to 15.9998 N-m/Amp.
Conversion formulas between N-m/Amp, in-lb/Amp, and oz-in/Amp,
are:
The denominator units of the required torque constant are peak Amps,
rather than rms Amps. To convert the torque constant from units of N-
m/Amp(rms), use the formula:
Many Allen-Bradley motors specify the torque constant in units of N-
m/rmsA/phase. In this case, in addition to conversion from rms Amps
to peak Amps, the value needs to be multiplied by three because it has
been defined as “per phase”.
Intro
1
Newton meter
Amp
8.85075
inch pound
Amp
141.612
ounce inch
Amp
⋅
=
⋅
=
⋅
Intro
1
Newton meter
Amp
0.707
Newton meter
Amp(rms)
⋅
=
⋅