Mitsubishi Electric FR-F700PJ Series, Instruction Manual

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145
Function assignment of external terminal and control
4
P
ARAM
ETE
R
S
(3) Speed detection hysteresis (Pr.870)
 This function prevents chattering of the speed detection
signals.
When an output frequency fluctuates, the up to frequency
signal (SU) and output frequency detection signals (FU) may
repeat ON/OFF (chatters). Setting hysteresis to the detected
frequency prevents chattering of these signals.
REMARKS
 All signals are OFF during DC injection brake.
 The output frequency compared with the set frequency changes depending on the control method.
NOTE
 Changing the terminal assignment using Pr.190 and Pr.192 (output terminal function selection) may affect the other
functions. Set parameters after confirming the function of each terminal.
Parameters referred to
Pr. 190, Pr. 192 (output terminal function selection)
(
Refer to page 140)
Pr.870
Pr.42
Output
frequency
(Hz)
ON
ON
ON
FU
OFF OFF
Example of output frequency detection signal (FU)
REMARKS
 Setting a higher value to this parameter slows the
response of frequency detection signals (SU and FU).
Control Method Compared Output Frequency
V/F control Output frequency
General-purpose magnetic flux
vector control
Output frequency before slip compensation
IPM motor control Estimated frequency (actual motor rotation per minute)