Terminal AM gain calibration [C1 (Pr. 901)]
Terminal AM is factory-set to provide a 10V DC output in the full-scale status of the correspond-
ing monitor item. Calibration parameter C1 (Pr. 901) allows the output voltage ratios (gains) to
be adjusted according to the meter scale. Note that the maximum output voltage is 10V DC, the
maximum output current 1mA.
Calibrate the terminal AM gain in the following procedure:
Connect an 0–10V DC voltmeter to inverter terminals AM and 5, taking care to correct with
the correct polarity. AM is positive.
Set Pr. 158 to select the monitor signal you want to output to analog output AM (refer to
page 6-146). To display the output frequency or the output current set Pr. 55 or Pr. 56,
respectively, to the maximum frequency or current value for which you want to output 10V
to the terminal.
Start the frequency inverter in PU mode with the operation panel or the control terminals
Calibrate the full deflection of the meter by setting C1 (Pr. 901) and then operating the digital
dial. Note that the value shown on the operating panel for the monitor signal associated with
C1 does not change when you turn the digital dial, but the analog voltage output to AM will
change as you turn the dial. Confirm the calibration value found by pressing the SET key
(this assigns the maximum voltage output to the displayed value of the monitor signal.)
If it is not possible output the signal to be measured for calibration at its maximum value you
can set Pr. 158 to "21". This outputs a continuous signal of approx. 10V to terminal AM,
which makes it possible to calibrate the maximum value on the meter. When C1 is used to
calibrate the full meter deflection in this mode a value of "1000" is displayed. Afterwards you
can then reset Pr. 158 to the required monitor signal setting.
Monitor display and monitor output signals
Connecting an analog meter to the AM output
Terminal AM gain calibration
of output signal
6 - 149