64
1018854 12/2015 V01
4. Actuator Selection Procedure
4.1. Selection Procedure and Calculation Example
Confirm the type of servo mechanism
required: linear motion or rotary motion
Calculate load torque (T
L
) and
moment of inertia (J
L
): Equation
Determine speed pattern from duty cycle
Tentatively select the required actuator
based upon load conditions
Calculate the required
acceleration torque (T
1
):
Equation 64.1
Is the required acceleration torque less than
max. output torque of the actuator?
No
Yes
Determine the torque pattern and
calculate the effective torque
(T
rms
):
Equation 64.2
Calculate average Speed (n
av
): Equation 64.3
Calculate duty factor (ED): Equation 64.4
T
rms
and n
av
are inside the
Continuous Duty Zone
No
Yes
Confirm final selection
Equation 64.1
Equation 64.2
Equation 64.3
Equation 64.4
T
1
= T
L
+
2
π
60
. (J
out
+ J
L
) . n
2
t
1
n
av
=
. t
1
+ n
2
. t
2
+ . t
3
t
1
+ t
2
+ t
3
+ t
p
n
2
2
n
2
2
ED =
t
1
+ t
2
+ t
3
t
1
+ t
2
+ t
3
+ t
p
. 100 %
T
2
= T
L
T
3
= T
L
.
(
T
1
–
T
L
)
T
rms
=
T
1
2
. t
1
+ T
2
2
. t
2
+ T
3
2
. t
3
t
1
+ t
2
+ t
3
+ t
p
65.4/65.6
ADVICE
We will be pleased to make a gear calculation and selection on your behalf. Please contact our application engineers.
Flowchart for actuator selection
