Mitsubishi Electric NF400-HEW, Instruction Manual

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6.5 How to use monitoring functions
6.5.1 MDU Breaker alarms
The alarm is output to display/over communication when the load current ≥ the pre-alarm current, and the duration ≥
the pre-alarm operating time (1/2 the long time delay operating time (TL)).
No settings. (The pick up value set on the MDU Breaker main unit.)
Set to either self-hold or automatic reset via communication or on the display.
Reset the alarm via communication or on the display.
Reset method
Self-hold
Automatic reset Automatically resets when the cause of the alarm is removed.
Alarm details
Setting method
Reset method
The alarm is output to display/over communication when the load current exceeds 105 to 125% of the current setting
of the circuit breaker.
No settings.
Automatic reset. (No settings.) Automatically resets when the cause of the alarm is removed.
Alarm details
Setting method
Reset method
(1) PAL (load current pre-alarm)
(2) OVER (overcurrent alarm)
The alarm is output to display/over communication when the electric current demand value (*) exceeds the pick up current.
Set via communication or on the display
Function: ON/OFF
Pick up current: 50 to 100% (per 1%)
Demand time limit: 1 to 10 min. (per 1 min), 15, 20, 25, 30 min. (*)
(Factory setting is OFF.)
Set to either self-hold or automatic reset via communication or on the display.
Reset the alarm via communication or on the display.
Reset method
Self-hold
Automatic reset Automatically resets when the cause of the alarm is removed.
Alarm details
Setting method
Reset method
(3) IDM_AL (electric current demand alarm)
* This differs from the demand time limit for each measurement value.
For automatic reset, the alarm will be reset
if the value falls below the pick up current.
For self-hold, the alarm will be maintained
and will need to be reset manually.
Alarm generated
Pick up current
Alarm reset
Time
Measurement
value