Справочник Пользователя для Hitachi L2002

Скачать
Страница из 304
L200
2
 Inverter
Oper
ations
and Monitor
ing
4–53
Analog Input Operation
The L200
2
 inverters provide for analog input 
to command the inverter frequency output 
value. The analog input terminal group 
includes the [L], [OI], [O], and [H] terminals 
on the control connector, which provide for 
Voltage [O] 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
must also set A001 = 01 to select analog input 
as the frequency source.
NOTE: If no logic input terminal is configured for the [AT] function, then inverter sums 
the voltage and current input to determine the desired input value.
Using an external potentiometer is a common 
way to control the inverter output frequency 
(and a good way to learn how to use the 
analog inputs). The potentiometer uses the 
built-in 10V reference [H] and the analog 
ground [L] for excitation, and the voltage 
input [O] for the signal. By default, the [AT] 
terminal selects the voltage input when it is OFF. Take care to use the proper resistance 
for the potentiometer, which is 1 to 2 k Ohms, 2 Watts.
Voltage Input – The voltage input circuit uses 
terminals [L] and [O]. Attach the signal 
cable’s shield wire only to terminal [L] on the 
inverter. Maintain the voltage within specifi-
cations (do not apply negative voltage).
Current Input – The current input circuit 
uses terminals [OI] and [L]. The current 
comes from a sourcing type transmitter; a 
sinking type will not work! This means the 
current must flow into terminal [OI], and 
terminal [L] is the return back to the transmit-
ter. The input impedance from [OI] to [L] is 
250 Ohms. Attach the cable shield wire only to terminal [L] on the inverter.
+V Ref.
A GND
Voltage input
Current input
L
H O OI
AM
+ –
4-20 mA, AT=ON
0-10 V, AT=OFF
[AT]
V/I input 
select
Freq.
setting
L
H O OI
AM
A001
1 to 2k
Ω, 2W
L
H O OI
AM
+ –
4 to 19.6 mA DC,
4 to 20 mA nominal
0 to 9.6 VDC,
0 to 10V nominal
See I/O specs on page 
L
H O OI
AM
L
H O OI
AM