Chapter 8 Mandatory Setting for Motor Drive and Test Run
8-1-2
8.1.2 Changing the Load Rating of the Inverter
 How to change to the load rating mode considered at the time of inverter selection?
 How to use the lower capacity inverter against the motor for light load applications such as fans
and pumps?
 The load rating mode of the inverter can be selected from the normal duty rating (ND) and the
low duty rating (LD).
 The rated current, overload current rating, temperature rating, etc. of the inverter differ
depending on the load rating mode. Select either one according to the load used.
â– Features of normal duty/low duty rating
Suitable for loads requiring high
torque at start,
acceleration/deceleration, etc.
Suitable for loads with less drive than
rated torque, etc. One size bigger
motor may be able to be driven.
Elevators, cranes, conveyors, etc.
Fans, pumps, air conditioners, etc.
Rated output current
(example)
3.0 A (3-phase 200 V, 0.4 kW inverter)
3.5 A (3-phase 200 V, 0.4 kW
inverter)
150%/1 minute, 200%/3 seconds
120%/1 minute, 150%/0.5 seconds
 The load rating mode is set in "Load type selection [b049]." Changing the [b049] and pressing
the SET key will immediately change the mode. As shown in the table below, the setting range
and the initial value of some parameters will be changed. Note that the setting values at that
time will also be initialized or changed.
Normal duty rating (ND mode)
Low duty rating (LD mode)
â– List of parameters changed when switching to normal duty rating
Default value after
initialization
Setting at
switching to ND
00(V/f constant torque)/
01(V/f reduction torque)/
02(Free-V/f)/
03(sensorless vector)
DC braking force at start
(0.20 to 1.00) × ND
rated current (A)
Free electronic thermal
current-1 to 3
(0.00 to 1.00) × ND
rated current (A)
Overload restriction 1
active level
(0.20 to 2.00) × ND
rated current (A)
1.5 × ND rated
current (A)
Overload restriction 2
active level
Active frequency
matching restart level
2.0 (kHz) [Pattern 0]
10.0 (kHz) [Pattern 1]
2.0 (kHz) [Pattern 3]
[Ao2] Output reference
value (at digital output
current monitor)
(0.20 to 2.00) × ND
rated current (A)
Low current detection level
0.00: Function disabled
(0.01 to 2.00) × ND
rated current (A)
1.15 × ND rated
current (A)
Same capacity as the
model
*1. "2nd-motor control [SET]" target parameter.