Mitsubishi Electric F700, Инструкция по эксплуатации

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167
Frequency setting by analog input (terminal 1, 2, 4)
4
PA
R
A
M
E
T
E
R
S
4.16.5 4mA input check of current input (Pr. 573)
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 173.)
When inputting 4 to 20mA current to terminal 2 or terminal 4, decrease in analog current input is detected to
enable continuous operation even if input has decreased.
Parameter
Number
Name Initial Value
Setting
Range
Description
573 4mA input check selection 9999
1
When the current input drops to or below 2mA,
the LF signal is output and inverter continues
operation at the frequency (average value) just
before current reaches 2mA.
9999 4mA input is not checked.
* When Pr.573 = "1", input decrease is detected (LF signal output) even if
the analog input value to bias frequency of terminal 2 or terminal 4 is set
to 2mA or less using
C2 (Pr. 902) or C5 (Pr. 904) and the value is not as
bias frequency settings.
(1) Operation at a current input decrease
continues (
Pr. 573
= "1")
˜
When the input current of terminal 4 (terminal 2) falls
2mA or below, output alarm output signal (LF) is output.
˜
When the current falls below 2mA, the output
frequency (average value) before detection is retained
and operation at the retained frequency continues.
˜
When the current input increases above 3mA, the
LF signal output is turned off and the inverter
operates according to the current input.
˜
For the LF signal, set "98 (positive logic) or 198
(negative logic)" in
Pr. 190 to Pr. 196 (output terminal
function selection)
and assign functions to the output
terminal.
˜
Since turning off the start command clears the
retained frequency, the inverter does not operate at
the retained frequency even if restarted.
CAUTION
· Changing the terminal assignment using Pr. 190 to Pr. 196 (output terminal function selection) may affect the other functions.
Make setting after confirming the function of each terminal.
4mA 2mA
60Hz
20mA
Set frequency
Analog input
When C3(C6) = 0%
Normal use range
Current input
decrease detection
*
2mA
3mA
Output frequency
During external operation (
Pr. 573
= 1)
STF
Input current
decrease
Time
Return
Operation
continue
Analog input
20mA
4mA
LF signal
Output frequency
Time
STF
20mA
4mA
LF signal
PID signal
Measured value
Set point (fixed)
Input current
decrease
2mA
3mA
Return
Operation
continue
On during input decrease
During PID control (reverse action) ( Pr. 573 = 1)