Delta VFD-B Series User Manual

Appendix C How to Select the Right AC Motor Drive|VFD-B-P Series
C-2 Revision April 2009, SW V1.00
C.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
375cos973
2
kVAdrivemotorACofcapacitythe
t
NGD
T
Nk
A
L
×≤
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
×+
××
×
ϕη
2. When one AC motor drive operates more than one motor
2.1 The starting capacity should be less than the rated capacity of AC motor drive
 Acceleration time
≦
60 seconds
The starting capacity=
()
[]
()
)(_____5.11
cos
111 kVAdrivemotorACofcapacitythek
n
n
Pknn
Nk
sCss
T
s
T
×≤+=+
×
×
⎥
⎥
⎥
⎦
⎤
⎢
⎢
⎢
⎣
⎡
−−
ϕη
 Acceleration time
≧
60 seconds
The starting capacity=
() [] ()
)(_____1
cos
111 kVAdrivemotorACofcapacitythek
n
n
Pknn
Nk
sCss
T
s
T
≤+=+
×
×
⎥
⎥
⎥
⎦
⎤
⎢
⎢
⎢
⎣
⎡
−−
ϕη
2.2 The current should be less than the rated current of AC motor drive(A)
 Acceleration time
≦
60 seconds
)(______5.111 AdrivemotorACofcurrentratedthek
n
n
In SM
T
S
T
×≤++
⎥
⎦
⎤
⎢
⎣
⎡
⎟
⎠
⎞
⎜
⎝
⎛
−
 Acceleration time
≧
60 seconds
)(______11 AdrivemotorACofcurrentratedthek
n
n
In SM
T
S
T
≤++
⎥
⎦
⎤
⎢
⎣
⎡
⎟
⎠
⎞
⎜
⎝
⎛
−
2.3 When it is running continuously

Delta VFD-B Series Specifications

General

Series	VFD-B
Cooling Method	Fan cooling
Overload Capacity	150% for 60 seconds
Braking Unit	Built-in
Control Mode	V/F control, Sensorless Vector Control
Communication	RS-485
Protection Features	Overvoltage, Undervoltage, Overcurrent, Overload, Overtemperature, Short Circuit
Operating Temperature	-10°C to +50°C
Storage Temperature	-20°C to +60°C
Humidity	90% RH (non-condensing)
Altitude	1000m (Derating required above 1000m)