Hitachi SJ300-037HFE 사용자 설명서

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SJ300 Inverter
Oper
ati
ons
and Monitor
ing
4–59
Analog Input Operation
Input Terminal 
Signals
The SJ300 inverters provide for an external analog 
input to command the inverter frequency output 
value. The analog input terminal group includes 
the [L], [OI], [O], [O2], and [H] terminals on the 
control connector, which provide for Voltage [O] 
and [O2] or Current [OI] input. All analog input 
signals must use the analog ground [L].
If you use either the voltage or current analog 
input, you must select one of them using the logic 
input terminal function [AT] analog type. If 
terminal [AT] is OFF, the voltage input [O] can 
command the inverter output frequency. If terminal 
[AT] is ON, the current input [OI] can command 
the inverter output frequency. The [AT] terminal function is covered in 
. Remember that you must also set A001 = 01 to select analog 
input as the frequency source.
Input Filter
Parameter A016 adjusts an analog input sampling filter that evenly affects all analog inputs 
shown above. The parameter range is from 1 to 30. Before increasing the filter setting, we 
recommend trying to find the cause of input analog noise. Check for the following:
• Look for nearby high-current wiring—avoid any parallel runs to the analog signal wires
• Check the impedance between the chassis grounds of the inverter and the analog signal 
source equipment—a good connection will have a low impedance
• Check the analog signal ground impedance from the inverter to the analog signal source
• Avoid ground loops... measure the current (or voltage drop) on the chassis ground and signal 
ground connections; the ideal value is zero
After taking steps to minimize the analog signal noise sources, increase the filter time constant 
(A016) until the motor output frequency (when commanded by analog inputs) becomes stable.
H O2
FM
AM
O
OI
L
AMI
+V Ref.
A GND
0—10V input
4—20mA input
-10 / 0 / +10V 
+ –
4-20 mA
Frequency
source setting
1
V – I select
0 – 10V
+ –
-10 / 0 / +10V
O2
O
O
OI
H O2
FM
AM
O
OI
L
AMI
A005
A001=01
A005=00
A005=01
AT=ON
AT=OFF
AT=ON
0
1
0
1
0
1
0
1
Frequency setting
Terminals
(Keypad)
OI
O2
O
L
AT