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4.4 Monitoring functions
4.4.1 Monitoring function list
Monitoring element
Fault cause
Electric current demand upper/lower limit alarm
Neutral line open phase alarm NLA (*2)
*1. Trip frequency and open/close frequency are enabled when “MDU transmission alarm switch (option)” and “MDU transmission auxiliary switch
(option)” are installed, respectively.
*2. This function is turned ON when the tline system is set to single-phase three-wire system. (The function is turned OFF when set to any
other line system.)
*3. For 250 A frame, the Load current pre-alarm is enabled when the PAL module (option) is installed.
*4. For 250 A frame, the Fault cause on Instantaneous is enabled when the MDU transmission alarm switch (option) is installed.
Load current pre-alarm PAL (*3)
Overcurrent alarm OVER
Electric current demand alarm
IDM_AL
Electric current unbalance alarm
IUB_AL
Electric current open phase
alarm ILA_AL
Long time delay
Short time delay
Instantaneous (*4)
Open/close frequency
Trip frequency
Display
●
●
●
●
●
–
–
●
●
●
–
●
Communication
●
●
●
●
●
●
●
●
●
●
●
–
MDU Breaker alarm
MDU Breaker status (*1)
●
The following table shows monitoring elements, along with elements that can be displayed on the display or communicated.
“
Display” indicates that the item is displayed on the display. “Communication” indicates that the item can be communicated through
CC-Link, MODBUS communication.
Summary of Contents for NF250-HEV
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