Hitachi SJ300-037HFE ユーザーズマニュアル

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Introduction to Variable-Frequency Drives
Geting Star
ted
1–16
Acceleration and deceleration settings 
specify the time required to go from a stop to 
maximum frequency (or visa versa). The 
resulting slope (speed change divided by 
time) is the acceleration or deceleration. An 
increase in output frequency uses the accel-
eration slope, while a decrease uses the 
deceleration slope. The accel or decel time a 
particular speed change depends on the 
starting and ending frequencies. However, 
the slope is constant, corresponding to the 
full-scale accel or decel time setting.
For example, the full-scale acceleration 
setting (time) may be 10 seconds—the time 
required to go from 0 to 60 Hz.
The SJ300 inverter can store up to 16 preset 
speeds. And, it can apply separate accelera-
tion and deceleration transitions from any 
preset to any other preset speed. A multi-
speed profile (shown at right) uses two or 
more preset speeds, which you can select via 
intelligent input terminals. This external 
control can apply any preset speed at any 
time. Alternatively, the selected speed is 
infinitely variable across the speed range. 
You can use the potentiometer control on the 
keypad for manual control. The drive 
accepts analog 0-10V signals and 4-20 mA 
control signals as well.
The inverter can drive the motor in either 
direction. Separate FW and RV commands 
select the direction of rotation. The motion 
profile example shows a forward motion 
followed by a reverse motion of shorter 
duration. The speed presets and analog 
signals control the magnitude of the speed, 
while the FW and RV commands determine 
the direction before the motion starts.
NOTE: The SJ300 can move loads in both directions. However, it is not designed for use in 
servo-type applications that use a bipolar velocity signal that determines direction.
Speed
Maximum speed
0
Acceleration
t
Acceleration (time) setting
Speed
Speed 1
Speed 2
t
Multi-speed Profile
Speed
Forward move
Reverse move
t
Bi-directional Profile