Terminal Fm Calibration (Calibration Parameter C0 (Pr. 900)) - Mitsubishi Electric FR-D720-0.4K Instruction Manual

4.11.4 Terminal FM calibration (calibration parameter C0 (Pr. 900))

By using the operation panel or parameter unit, you can calibrate terminal FM to full scale deflection.
Parameter
Name
Number
C0 (900) FM terminal calibration
∗1
The above parameter can be set when Pr. 160 Extended function display selection = "0". (Refer to page 163)
∗2
The parameter number in parentheses is the one for use with the operation panel (PA02) for the FR-E500 series or parameter unit (FR-PU04/FR-PU07).
∗3
The above parameter allows its setting to be changed during operation in any operation mode even if "0" (initial value) is set in Pr. 77 Parameter write
selection.
(1) FM terminal calibration (C0 (Pr. 900))
The terminal FM is preset to output pulses. By setting the FM terminal calibration C0 (Pr. 900), the meter connected to the
inverter can be calibrated by parameter setting without use of a calibration resistor.
Using the pulse train output of the terminal FM, a digital display can be provided to connect a digital counter.
The monitor value is 1440 pulses/s output at the full-scale value of monitor description list (page 129) (Pr. 54 FM terminal
function selection).
FM
Calibration
resistor *1
SD
∗1
Not needed when the operation panel or parameter unit (FR-PU04/FR-PU07) is used for calibration.
Use a calibration resistor when the indicator (frequency meter) needs to be calibrated by a neighboring device because the indicator is located far from
the inverter.
However, the frequency meter needle may not deflect to full-scale if the calibration resistor is connected. In this case, perform calibration using the
operation panel or parameter unit.
∗2
The initial settings are 1mA full-scale and 1440 pulses/s terminal FM frequency at 60Hz.
Calibrate the terminal FM in the following procedure.
1) Connect an indicator (frequency meter) across terminals FM-SD of the inverter. (Note the polarity. The terminal FM is
positive)
2) When a calibration resistor has already been connected, adjust the resistance to "0" or remove the resistor.
3) Refer to the monitor description list (page 129) and set Pr. 54.
When you selected the running frequency or inverter output current at monitor, preset the running frequency or
current value, at which the output signal will be 1440 pulses/s, to Pr. 55 Frequency monitoring reference or Pr. 56 Current
monitoring reference.
At 1440 pulses/s, the meter generally deflects to full-scale.
REMARKS
When calibrating a monitor output signal, which cannot be adjusted to 100% value without an actual load and a measurement
equipment, set Pr. 54 to "21" (reference voltage output). 1440 pulses/s are output from the terminal FM.
The wiring length of the terminal FM should be 200m at maximum.
NOTE
The initial value of the calibration parameter C0 (Pr. 900) is set to 1mA full-scale and 1440 pulses/s FM output frequency
at 60Hz. The maximum pulse train output of terminal FM is 2400 pulses/s.
When a frequency meter is connected across terminals FM to SD to monitor the running frequency, the terminal FM
output is filled to capacity at the initial value if the maximum output frequency reaches or exceeds 100Hz. In this
case, the Pr. 55 setting must be changed to the maximum frequency.
Initial Value
—
Indicator
1mA full-scale
analog meter
1mA
(+) (-)
8VDC
Pulse width T1: Adjust using calibration parameter C0
Pulse cycle T2: Set with Pr. 55 (frequency monitor)
Set with Pr. 56 (current monitor)
Monitor display and monitor output signal
Setting Range
—
FM
T1
SD
T2
Description
Calibrates the scale of the meter
connected to terminal FM.
(Digital indicator)
1440 pulses/s(+)
(-)
4
135