Hitachi SJ300-037HFE 사용자 설명서

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“A” Group: Standard Functions
Configur
ing Dr
iv
P
a
ra
meters
3–24
Optimal Accel/Decel Operation, continued...
The acceleration time is controlled to maintain output current below the level set by the 
Overload Restriction Function if enabled (Parameters B021/B024, B022/B025, and B023/
B026). If Overload Restriction is not enabled, then the current limit used is 150% of the 
inverter’s rated output current.
The deceleration time is controlled so that the output current is maintained below 150% of the 
inverter’s rated current, and the DC bus voltage is maintained below the OV Trip level (358V or 
770V).
NOTE: DO NOT use Optimal Accel/Decel (A085 = 02) when an application...
•  has a requirement for constant acceleration or deceleration
•  has a load inertia more than (approx.) 20 times the motor inertia
•  uses internal or external regenerative braking
•  uses any of the vector control modes (A044 = 03, 04, or 05). This function is ONLY
   compatible with V/F control.
NOTE: If the load exceeds the rating of the inverter, the acceleration time may be increased.
NOTE: If using a motor with a capacity that is one size smaller than the inverter rating, enable 
the Overload Restriction function (B021/B024) and set the Overload Restriction Level (B022/
B025) to 1.5 times the motor nameplate current.
NOTE: Be aware that the acceleration and deceleration times will vary, depending on the 
actual load conditions during each individual operation of the inverter.
Second
Acceleration and 
Deceleration 
Functions
The SJ300 inverter features two-stage acceleration and deceleration ramps. This gives flexibil-
ity in the profile shape. You can specify the frequency transition point, the point at which the 
standard acceleration (F002) or deceleration (F003) changes to the second acceleration (A092) 
or deceleration (A093). These profile options are also available for the second motor settings 
and third motor settings. All acceleration and deceleration times are time to ramp from zero 
speed to full speed or full speed to zero speed. Select a transition method via A094 as depicted 
below. Be careful not to confuse the second acceleration/deceleration settings with settings for 
the second motor!
Accel 1
Accel 2
2CH 
input
Accel 1
Accel 2
Frequency
transition point
A095
A094=00
A094=01
t
t
frequency
frequency
0
0
1