Fagor DDS Series User Manual

Selection criteria
5.
Ref.1912
· 211 ·
DDS
HARDWARE
Calculation of acceleration and braking time
After selecting the mechanical characteristics and the power of the drive, the
acceleration and braking time is calculated as follows:
Calculation of power with intermittent load
Forming the drive to the right dimensions has to be done with the greatest
care when the application involves a periodical starting and stopping
operation, frequently repeated as in the case of threading with a miller.
For a cycle like the one shown in the figure
F. H5/11 which includes
acceleration and stopping, the equivalent effective torque
T
R
of equation
must be within the S1 dimension given for the drive torque.
Drive selection
When selecting an FM7|FM9 motor, see the manual of the AC spindle
motor that indicates the drive associated with the selected motor.
Constant torque
area:
(0 < N
M
< N
B
)
Constant power
area:
(N
B
< N
M
< N
max
)
Constant torque &
power area:
(N
B
< N
M
< N
max
)
J
M
Inertia of the load in kg·m² as viewed from the motor shaft
T
M
Rated torque at base speed in N·m
Nmax
Maximum motor speed in rpm.
N
B
Motor base speed in rpm.
N
M
Motor speed reached after a time period t in rpm
F. H5/11
Periodic start-stop operation
t
1
2 J
M
N
M

60 T
M

------------------------------- s=
t
2
2 J
M
N
M
2
N
B
2
–
120 T
M
N
B

-----------------------------------------------------s=
t
3
t
1
t
2
+
2 J
M
N
M
2
N
B
2
+
120 T
M
N
B

--------------------------------------------------- s==
0
speed
0
torque
Tc
time
Nm
TL
Tp
-Tp
Tr TfTs
time
T
R
T
P
2
t
r
t
f
+ T
L
2
t
s
+
t
c
-------------------------------------------------------
Nm=

Fagor DDS Series Specifications

General

Brand	Fagor
Model	DDS Series
Category	DC Drives
Language	English