Hitachi hitachi series inverter user manual Analog Input Operation, Am H O Oi L

Analog Input Operation

The WJ200 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. Refer to the table on next page showing the activation of

each analog input by combination of A005 set parameter and [AT] terminal condition. The [AT] terminal function is covered in “Analog Input Current/Voltage Select” in section 4. Remember that you must also set A001 = 01 to select analog input as the frequency source.

AM H O OI L

+V Ref.

Voltage input

Current input

A GND

V/I input
select	A001
[AT]	Freq.
	setting
AM H O OI	L
	4-20 mA
+ -	0-10 V

NOTE: If no logic input terminal is configured for the [AT] function, then inverter recognizes that [AT]=OFF and MCU recognizes [O]+[OI] as analog input.

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 1~2 kΩ, 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 specifications (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 transmitter. The input impedance from [OI] to

[L]is 100 Ohms. Attach the cable shield wire only to terminal [L] on the inverter.

AM H O OI L

1 to 2kΩ, 2W

	AM	H	O	OI	L
0 to 9.6 VDC,				+ -
0 to 10V nominal
	AM	H	O	OI	L

4 to 19.6 mA DC,

4 to 20mA nominal

See I/O specs on page 21,22.

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