Mitsubishi Electric 800 Series Instruction Manual page 340

 Analog current input loss condition (Pr.778)
• When the condition of current input to the terminal 4 (terminal 2) continues to be 2 mA or less for Pr.778 setting time, it is
considered as loss of analog current input and alarm (LF) signal is turned ON. The LF signal will turn OFF when the current
input becomes 3 mA or higher.
• For the LF signal, set "98 (positive logic) or 198 (negative logic)" in any of Pr.190 to Pr.196 (Output terminal function
selection) to assigns the function.
*1 When the Pr.573 ≠ "9999" and terminal 4 (terminal 2) is calibrated to 2 mA or less with Pr.902 (Pr.904), analog input frequency that is 2 mA or
less will become input current loss, thus it will not be as the bias setting frequency.
NOTE
• Changing the terminal assignment using Pr.190 to Pr.196 (Output terminal function selection) may affect the other
functions. Set parameters after confirming the function of each terminal.
 Continue operation at analog current input loss (Pr.573 = "1, 4, 11, 14, 21,
or 24", Pr.777)
• When Pr.573 = "1, 11, or 21", operation is continued with the output frequency before the current input loss.
• When Pr.573 = "4, 14, or 24" and Pr.777 ≠ "9999", operation is continued with frequency set in Pr.777.
• When the start command is turned OFF during the input current loss, deceleration stop is immediately performed, and the
operation is not restored even if start command is input again.
• When the current input is restored, the LF signal is turned OFF, and operation is performed according to the current input.
• The following is the operation example during External operation.
Output frequency
Analog input
20 mA
4 mA
STF
LF signal
Set frequency
60 Hz
Current input
decrease detection
∗1
2 mA 4 mA
Normal use range
Pr.573=1, 11, 21 : Operation continued with the frequency before being lost
Pr.573=4, 14, 24 : Operation continued with Pr.777 setting
Input current
decrease
2 mA
When Pr.902 (Pr.904) = 0%
20 mA
Analog input
Return
3 mA
5.9 (T) Multi-Function Input Terminal Parameters
Time
5. PARAMETERS
3
4
5
5
5
6
7
8
9
10
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