Hitachi SJ300 Series [FM] Terminal, PWM Signal Type, Func, Code, Note 1:, Waveform, Description, Full Scale Value

4–62

Analog Output Operation

Analog Output Operation

In the system design for inverter applications it is sometimes useful to monitor inverter operation from a remote location. In some cases, this requires only a panel-mounted analog meter (moving-coil type). In other cases, a controller device such as a PLC may monitor and command the inverter frequency and other functions. The inverter can transmit the (real-time) output frequency, current, torque, or other parameters to the controller to confirm actual opera- tion. The monitor output terminal [FM] serves these purposes.

[FM] Terminal The inverter provides an analog/digital output on terminal [FM] (frequency monitor). It uses terminal [CM1] as digital GND reference. While many applications use this terminal to monitor the output frequency, you can configure terminal [FM] to transmit one of several parameters. Most use pulse-width modulation (PWM) to represent the value, while one parameter uses frequency modulation (FM) to represent the value. Do not confuse the notation for terminal [FM] (with brackets) with FM signal type.

H O2 AM FM TH FW

LO OI AMI P24PLCCM1 Analog/digital Output

D GND

See I/O specs on page 4–9.

Operations and Monitoring

The following table lists the configurations for terminal [FM]. Use function C027 to configure.

Func.

Code

Description

Waveform

Full Scale Value

00

Output frequency

PWM

0 – Max. frequency (Hz)

01

Output current

PWM

0 – 200%

02

Output torque *1

PWM

0 – 200%

C027

03

Output frequency

FM

0 – Max. frequency (Hz)

04

Output voltage

PWM

0 – 100%

05

Input electric power

PWM

0 – 200%

06

Thermal load ratio

PWM

0 – 100%

07

LAD frequency

PWM

0 – Max. frequency (Hz)

Note 1: Display substitutes only during sensorless vector control, 0Hz domain sensorless

vector control, and vector control

PWM Signal Type The pulse-width modulated signal at terminal

H

O2

AM

FM

TH

FW

[FM] is primarily designed for driving a moving-

coil meter. The pulse-width modulated signal is

L

O

OI

AMI

P24

PLC

CM1

automatically averaged by the inertia of the

moving-coil mechanism—converting the PWM

+

–

signal to an analog representation. Be sure to use

a 10V full-scale DC voltmeter.

0 to 10V,

The signal characteristics of terminal [FM] in

1 mA

PWM signal configuration is shown below

[FM]

t

[FM] output value =

t

---

10V

T

= [FM] terminal 8-bit gain setting

B081

0V

C27=00, 01, 02, 04, 05, 06, 07

T

t

Selects FM type output

Period T = 6.4ms constant (156 Hz)