3.2 Starting and Stopping Time
3.2 Starting and Stopping Time
The motor starting (tr) and stopping time (tf) with a constant load are calculated using the following
equations. Motor viscous torque and friction torque have been ignored.
Starting time: tr = 104.7 x NR(JAI J L ) [ m s ]
Kt • IR(a-13)
NR(JM +
Stopping time: = 104.7
x
„
[ms]
Kt • IR(a + 13)
NR:
JM:
JL:
Rated motor speed (r/min)
Motor moment of inertia (kg/m2)...(GD2m/4)
Load converted to shaft moment of inertia (kg/m2)...(GD21/4)
Tpm: Maximum instantaneous motor torque obtained in combination with SERVOPACK (N • m)
TL: L o a d torque (N• m)
To convert the motor current value into an equivalent torque value, use the following formula:
Motor torque constant x motor current value (effective value)
Motor torque
Motor speed
F-
F-
t r
A
Time
lw T i m e
Figure 3.2 M o t o r Torque — Motor Speed Timing Chart
3 -3
