Emerson Control Techniques FM-4 Reference Manual page 249

For horizontal loads or counterbalanced vertical loads use the following formula:
Where:
IR = Inertia Ratio
R = ramp in ms/kRPM
Ta = (unsigned) percent continuous torque required during acceleration ramping (0 - 300)
Td = (unsigned) percent continuous torque required during deceleration ramping
(0 - 300)
Vm = motor constant value from Table 18 below
For un-counter balanced vertical loads use the following formula:
Where:
IR = Inertia Ratio
R = ramp in ms/kRPM
Vm = motor constant value from the table below
Tau = (unsigned) percent continuous torque required during acceleration ramping while moving up (against the
constant force)
Tdu = (unsigned) percent continuous torque required during deceleration ramping while moving up (against the
constant force)
Tad = (unsigned) percent continuous torque required during acceleration ramping while moving down (aided by the
constant force)
Tdd = (unsigned) percent continuous torque required during deceleration ramping while moving down (aided by the
constant force)
Ramp Units Conversion
If you are using an external position controller to generate motion you may need to connect the ramp units as desired below.
Many position controllers define acceleration in units per sec
conversion when entering the information into the formula.
Conversion Formula:
Where:
MPK = accel ramp in ms/kRPM
RPSS = accel ramp in revolutions per second
Motor
NT-320
MG-205
MG-208
MG-316
(R • Vm (Ta + Td))
IR =
2000
(R • Vm (Tau + Tud
IR =
4000
6
10
=
MPK
•
(RPSS 60)
Drive Vm
4.30
4.77
EN-204
5.11
3.17
− 1
+ Tad + Tdd))
− 1
2
. The formulas above use ms/kRPM. Make sure you make this
2
Percent Continuous/volt
RPM /volt Scaled Velocity
Scaled Torque Command
Command Output (default))
Output (default))
30
30
30
30
Tuning Procedures
600
600
600
600
235