Specifications
101
Supplements
Formula for Calculating Motor Capacity
Symbols (For P.94)
●
Rotary motion
●
Linear motion
Motor
¶
NM
GD
2
M
Vƒ
Tƒ
Nƒ
W
Motor
NM
GD
2
M
¶
PM : Motor shaft output required for the load〔kW〕
PO : Running power kW kW
TM : Motor rated torque N・m kg・m
TL :
Load torque (reflected to motor shaft)
N・m kg・m
T
ƒ : Load torque (load axis) N・m kg・m
PM : Motor rated output kW kW
NM : Motor rated speed min
-1
rpm
Nƒ : Load axis rotation speed min
-1
rpm
NM : Motor axis rotation speed min
-1
rpm
Vƒ : Load speed m/min m/min
W : Mass of load kg kg
(SI Units) (MKS Units)
¶
: Gear efficiency
µ
: Friction factor
J
M : Motor moment of inertia kg・m
2
kg・m
2
J
L :
Load moment of inertia (motor axis)
kg・m
2
kg・m
2
J
ƒ :
Load moment of inertia (load axis)
kg・m
2
kg・m
2
T
A : Acceleration torque N・m kg・m
T
B : Braking torque N・m kg・m
t
a : Starting time s s
t
d : Braking time s s
¡
: Accel torque factor(1.0 to 1.5)
™ :
Regenerative braking factor, without braking resister(Less than 0.2)
with braking resister(0.3 to 1.5)
(SI Units) (MKS Units)
¶ : Motor efficiency (normally, approx. 0.85)
cosφ: Motor power factor (normally, approx. 0.75)
VM : Motor voltage [V]
IM : Motor current [A]
(current with commercial power supply)
k :
Correction factor calculated from current distortionCorrection factor calculated from current distortion
factor (1.0 to 1.05, depending on the PWM method.)factor (1.0 to 1.05, depending on the PWM method.)
NM : Motor rotation speed〔min
-1
〕
PC1 : Continuous capacity〔kVA〕
k
S
: Motor starting current/motor rated current
n
T
: Number of motors in parallel
n
S
: Number of simultaneously started motors
GD
2
: Total (GD
2
) reflected into motor shaft〔kg・m
2
〕
tA : Motor acceleration time
TL : Load torque〔N・m〕
SI Units (International Units)
T
M = × 10
3
[N・m]
MKS Units (Gravimetric Units)
SI Units (International Units) MKS Units (Gravimetric Units)
60 ・ PM
2π ・ NM
TL = [N・m]
9.8・
µ
・ W ・ Vƒ
2π ・ NM ・
¶
9.8・
µ
・ W ・ Vƒ
60 ・
¶
Po = × 10
-3
[kW]
T
A
= + TL[N・m]
[kg・m
2
]
(
JM + JL )NM
ta
TB
=
-
TL[N・m]
(
JM + JL )NM
td
J
L
=
( )
2
Nƒ
NM
J
L
= W
( )
2
1
4
1
4
= GD
2
L
・ J
ƒ
Vƒ
π ・ NM
W
( )
2
=
Vƒ
π ・ NM
Vƒ
NM
W・0.1013・
( )
2
TM = [kg・m]
974 ・ PM
NM
TL = [kg・m]
µ
・ W ・ Vƒ
2π ・ NM ・
¶
PO = [kW]
µ
・ W ・ Vƒ
6120 ・
¶
TA
=
+ TL
[kg・m]
[kg・m
2
]
(GD
2
M + GD
2
L )NM
375・ ta
-
TL
[kg・m]
(GD
2
M + GD
2
L )NM
375・ td
TB
=
GD
2
L
=
( )
2
・ GD
2
ƒ
GD
2
L
=
Nƒ
NM
TM = × 10
3
[N・m]
60 ・ PM
2π ・ NM
TL = [N・m]
N
ƒ
Tƒ
NM ・
¶
Tƒ ・ Nƒ
¶
PO = ・ × 10
−3
[kW]
2π
60
t
a
=
[kg・m
2
]
t
d
=
J
L
=
( )
2
Nƒ
NM
・ J
ƒ
TM = [kg・m]
974 ・ PM
NM
PO = [kW]
T
ƒ ・ NNƒ
974 ・
¶
t
a
= [
s
]
[kg・m
2
]
( GD
2
M + GD
2
L )・ NM
375(
¡
・ TM − TL )
t
d
=
GD
2
L
=
( )
2
・ GD
2
ƒ
Nƒ
NM
[
s
]
( GD
2
M + GD
2
L )・ NM
375( ™ ・ TM + TL )
( J
M + J
L )・ NM
(
¡
・ TM − TL )
・ [
s
]
2π
60
・
2π
60
・
2π
60
( J
M + J
L )・ NM
( ™ ・ TM + TL )
・ [
s
]
2π
60
TL = [kg・m]
N
ƒ
Tƒ
NM ・
¶










