User manual

QBL5704 Manual (V1.00 /09-May-2007) 8
Copyright © 2007, TRINAMIC Motion Control GmbH & Co. KG
5.2 RMS torque requirement
Root-Mean-Square or RMS torque is a value used to approximate the average continuous torque
requirement. Its statistical approximation is with
t1: acceleration time t2: run time t3: deceleration time t4: time in a move
()( )
4321
3
2
FLJ2
2
FL1
2
P
RMS
tttt
tTTTtTTtT
T
+++
⋅−−+⋅++⋅
=
5.3 Motor velocity
The motor velocity is also dictated by the configuration of the mechanical system that is coupled to
the motor shaft, and by the type of move that is to be effected. For example, a single velocity
application would require a motor with rated velocity equal to the average move velocity. A point to
point positioning would require a motor with a rated velocity higher than the average move velocity.
(The higher velocity would account for acceleration, deceleration and run times of the motion profile).
Figure 5.1 relates rated motor velocity to average move velocity for two point to point positioning
move profiles.
Figure 5.1: Rated motor velocity to average move velocity for point to point positioning