Appendix B How to Select AC Motor Drive
|
DD Series
B-2
B-1 Capacity Formulas
1. When one AC motor drive operates one motor
The starting capacity should be less than 1.5x rated capacity of AC motor drive
The starting capacity=
)
(
_
_
_
_
_
5
.
1
375
cos
973
2
kVA
drive
motor
AC
of
capacity
the
t
N
GD
T
N
k
A
L
×
≤
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
×
+
×
×
×
ϕ
η
2. When one AC motor drive operates more than one moto
r
2.1 The starting capacity should be less than the rated capacity of AC motor drive
Acceleration time
≦
60 seconds
The starting capacity=
(
)
[
]
(
)
)
(
_
_
_
_
_
5
.
1
1
cos
1
1
1
kVA
drive
motor
AC
of
capacity
the
k
n
n
P
k
n
n
N
k
s
C
s
s
T
s
T
×
≤
+
=
+
×
×
⎥
⎥
⎥
⎦
⎤
⎢
⎢
⎢
⎣
⎡
−
−
ϕ
η
Acceleration time
≧
60 seconds
The starting capacity=
(
)
[
]
(
)
)
(
_
_
_
_
_
1
cos
1
1
1
kVA
drive
motor
AC
of
capacity
the
k
n
n
P
k
n
n
N
k
s
C
s
s
T
s
T
≤
+
=
+
×
×
⎥
⎥
⎥
⎦
⎤
⎢
⎢
⎢
⎣
⎡
−
−
ϕ
η
2.2 The current should be less than the rated current of AC motor drive(A)
Acceleration time
≦
60 seconds
)
(
_
_
_
_
_
_
5
.
1
1
1
A
drive
motor
AC
of
current
rated
the
k
n
n
I
n
S
M
T
S
T
×
≤
+
+
⎥
⎦
⎤
⎢
⎣
⎡
⎟
⎠
⎞
⎜
⎝
⎛
−
Acceleration time
≧
60 seconds
)
(
_
_
_
_
_
_
1
1
A
drive
motor
AC
of
current
rated
the
k
n
n
I
n
S
M
T
S
T
≤
+
+
⎥
⎦
⎤
⎢
⎣
⎡
⎟
⎠
⎞
⎜
⎝
⎛
−
2.3 When it is running continuously
The
requirement
of load capacity should be less than the capacity of AC motor drive(kVA)
The requirement of load capacity=
)
(
_
_
_
_
_
cos
kVA
drive
motor
AC
of
capacity
the
P
k
M
≤
×
×
ϕ
η
The motor capacity should be less than the capacity of AC motor drive
)
(
_
_
_
_
_
10
3
3
kVA
drive
motor
AC
of
capacity
the
I
V
k
M
M
≤
×
×
×
×
−
The current should be less than the rated current of AC motor drive(A)
)
(
_
_
_
_
_
_
A
drive
motor
AC
of
current
rated
the
I
k
M
≤
×
Summary of Contents for VFD-DD Series
Page 1: ......
Page 13: ...Chapter 1 Introduction DD Series 1 7 ECMD B9160GMS...
