Analog output operation, Analog output operation 4–55, Analog output operation” on – Hitachi L2002 User Manual
Page 199
L200
2
Inverter
Oper
ations
and Monitor
ing
4–55
Analog Output Operation
In inverter applications it is useful to monitor
the inverter operation from a remote location or
from the front panel of an inverter enclosure. In
some cases, this requires only a panel-mounted
volt meter. In other cases, a controller such as a
PLC may provide the inverter’s frequency
command, and require inverter feedback data
(such as output frequency or output current) to
confirm actual operation. The analog output
terminal [AM] serves these purposes.
The inverter provides an analog voltage output on terminal [AM] with terminal [L] as
analog GND reference. The [AM] can output inverter frequency or current output value.
Note that the voltage range is 0 to +10V (positive-going only), regardless of forward or
reverse motor rotation. Use C028 to configure terminal [FM] as indicated below.
The [AM] signal offset and gain are adjustable, as indicated below.
The graph to the right shows the effect of the
gain setting. To calibrate the [AM] output for
your application, follow the steps below:
1. Verify that the inverter is in Stop Mode.
2. Use C086 to adjust the offset voltage. The
factory default (0V) is the correct value for
most cases. Otherwise, you can have a
positive voltage at zero speed or current.
3. Run the motor at the full scale speed.
a. If [AM] represents output frequency, use
B080 to set the voltage for full scale
output (up to 10V).
b. If [AM] represents motor current, use B080 to set the voltage for full scale
output. Remember to leave room at the upper end of the range for increased
current when the motor is under heavier loads.
Func.
Code
Description
Range
C028
00
Output frequency
0 – Max. frequency (Hz)
01
Output current
0 – 200%
Func.
Description
Range
Default
B080
[AM] analog signal gain
0 to 255
100
C086
[AM] terminal offset tuning
0 – 10V
0.0
A GND
Analog
Voltage
Output
See I/O specs on page
.
+
–
10VDC
full scale,
1mA max
L
H O OI
AM
[AM]
Hz
or
A
0
1/2 full
scale
Full
scale
output
B080=200%
B080=100%
B080=50%
10V
5V