Specifications
100
MMMMSupplements
Inverter Capacity Selection
●
Inverter Capacity Check Points
●
Inverter Capacity Required for Continuous Operation
●
Inverter Capacity Required for Group Drive
●
Inverter Capacity Required for Starting
Classification
Load
Characteristics
Load type
Load speed
and torque
characteristics
Load
characteristics
Continuous operation
Long-time operation at medium or low speeds
Short-time operation
Friction load and weight load
Liquid (viscous) load
Inertia load
Load with power transmission and accumulation
○
○
○
○
○ ○
○ ○
○
○
○
○
○ ○
○ ○
○
○
Constant torque
Constant output
Decreasing torque
Decreasing output
Motoring
Braking or overhauling load
Constant load
Shock load
Repetitive load
High-start torque
Low-start torque
Maximum required output (instantaneous)
Constant output (continuous)
Maximum min
-1
Rated min
-1
Power supply transformer capacity percentage impedance
Voltage fluctuations
Number of phases, single phase protection
Frequency
Mechanical friction, losses in wiring
Duty cycle modification
Operation
Rated Output
Rated min
-1
Deterioration of Load
Capacity due to Age
Power Supply
Item
Related Specification
Speed and Torque
Characteristics
Time
Ratings
Overload
Capacity
Starting
Torque
Item
Item
Item
Motor acceleration of 1 minute or less Motor acceleration of 1 minute or more
Calculation formula
Calculation formula (with overload capacity of 150 ％ for 1 minute)
Calculation formula [t
A＜60 s]
Required output for the load within
the allowable range
Motor capacity within the inverter
ratings
Current within the inverter ratings
Starting requirements are within the
inverter capacity
Current within the inverter capacity
Total starting capacity within the
inverter capacity
Inverter capacity [kVA]
Inverter capacity [kVA]
k
k
k
Inverter capacity [A]
P
M
V
M
I
M
I
M
η × cosφ
3
×
×
×
× 10
−3
× ×
≦
≦
≦
P
M
P
C1
η× cosφ
− 1＋
1 ＋
n
S
×
＝
≦ 1.5 × Inverter capacity [kVA]
{
{}
()
− 1
()
}
n
T
n
T
− 1＋ n
S
n
S
{()}
I
M
×
≦ Inverter capacity [kVA]
1 ＋
{}
− 1
)
P
M
η× cosφ
×
P
C1
1 ＋
＝
≦ Inverter capacity [kVA]
{}
− 1
()
n
T
n
S
k
×
k
×
k
k
k
S
k S
n
T
(
n
T
n
S
k S
k S
k Sn
T
I
M
×
≦ 1.5 × Inverter capacity [A]
1 ＋
{}
− 1
)(
n
T
n
T
n
S
k S
≦ 1.5 × Inverter capacity [kVA]
375
× GD
2
＋ ×
974
×
η
×
cosφ
N
M
T
L
N
M
t
A
k