138
Monitor display and monitor output signal
4.11.4 Terminal FM, AM calibration
(Calibration parameter C0 (Pr. 900), C1 (Pr. 901))
(1) FM terminal calibration
(C0(Pr.900))
⋅
The terminal FM is preset to output pulses. By setting the
Calibraton parameter 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 by a digital counter. The monitor
value is 1440 pulses/s output at the full-scale value of the table on the previous page
(Pr. 54 FM terminal function
selection)
.
⋅
Calibrate the terminal FM in the following procedure.
1) Connect an indicator (frequency meter) across the 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 131)
and set
Pr. 54
. When you selected the running frequency or
inverter output current as the 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.
By using the operation panel or parameter unit, you can calibrate terminal FM and terminal AM to full scale
deflection.
Parameter
Number
Name
Initial Value
Setting Range
Description
C0(900)
FM terminal calibration
⎯
⎯
Calibrates the scale of the meter
connected to terminal FM.
C1(901)
AM terminal calibration
⎯
⎯
Calibrates the scale of the analog
meter connected to terminal AM.
*1
The above parameters can be set when
Pr. 160 User group read selection
= "0".
(Refer to page 175.)
*2
The parameter number in parentheses is the one for use with the parameter unit (FR-PU04/FR-PU07).
*3
The above parameters allow 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
Not needed when the operation panel (FR-DU07) or parameter unit (FR-PU04/FR-PU07) is used for calibration.
This resistor is used when calibration must be made near the frequency meter for such a reason as a remote frequency meter.
Note that the needle of the frequency meter may not deflect to full-scale when the calibration resistor is connected. In this case, use
this resistor and perform calibration of operation panel or parameter unit.
*2
The initial settings are 1mA full-scale and 1440 pulses/s terminal FM frequency at 60Hz.
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.
1440 pulses/s are output
from the terminal FM.
⋅
The wiring length of the terminal FM should be 200m maximum.
CAUTION
⋅
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 to across terminals FM-SD to monitor the running frequency, the FM terminal output
is filled to capacity at the initial setting if the maximum output frequency reaches or exceeds 100Hz. In this case, the
Pr. 55
setting must be changed to the maximum frequency.
8VDC
T2
T1
Pulse width T1: Adjust using calibration parameter C0
Pulse cycle T2: Set with
Pr. 55
(frequency monitor)
Set with
Pr.56
(current monitor)
(Digital indicator)
(-)
1440 pulses/s(+)
FM
SD
Indicator
1mA full-scale
analog meter
(+)
1mA
FM
SD
Calibration
resistor
*1
(-)
