Mitsubishi Electric EMU4-FD1-MB, User Manual

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How to use upper/lower limit alarm function
This device can set the upper/lower limit alarm value for each measured value individually.
<Monitoring items>
Upper limit alarm items Current demand, phase N current demand, Voltage, Electric power demand,
Power factor, Pulse count
Lower limit alarm items Current demand, Voltage, Electric power demand, Power factor,
<Alarm setting>
・
Upper limit value Set the upper limit of measured value. For setting value and setting range, p.26,27
・
Lower limit value Set the lower limit of measured value. For setting value and setting range, p.26,27
・
Alarm delay time Set the value in case you want to remove the inrush current of the load, etc. from the objects of
monitoring. Alarm does not occur when the measured value goes below the upper limit or goes over
the lower limit within the configured time. For setting value and setting range, page 27.
・
Alarm reset method Alarm recovery operation is different according to the alarm reset method.
Reset method Alarm recovery operation
Auto-reset (Auto) Reset the alarm automatically if the measured value goes below the upper
limit or goes over the lower limit.
Self-retention
(HoLd)
The alarm is held after the measured value goes below the upper limit or
goes over the lower limit. Alarm is cleared by alarm reset.
For setting, page 27. For alarm reset operation, page 55.
<Alarm occurrence / recovery condition>
Alarm item
Alarm reset
method
Alarm status Alarm occurrence / recovery condition
Current demand
Phase N current demand
Voltage
Electric power demand
Power factor
Auto-reset
(Auto)
Upper limit
monitoring
Occurrence
Measured value > configured upper limit
(Alarm delay time is available)
Recovery Measured value ≤ configured upper limit
Lower limit
monitoring
Occurrence
Measured value < configured lower limit
(Alarm delay time is available)
Recovery Measured value ≥ configured lower limit
Self-retention
(HoLd)
Upper limit
monitoring
Occurrence
Measured value > configured upper limit
(Alarm delay time is available)
Retention Measured value ≤ configured upper limit
Recovery
Measured value ≤ configured upper limit
AND
Alarm reset
Lower limit
monitoring
Occurrence
Measured value < configured lower limit
(Alarm delay time is available)
Retention Measured value ≥ configured lower limit
Recovery
Measured value ≥ configured lower limit
AND
Alarm reset
Pulse count
Auto-reset
(Auto)
Upper limit
monitoring
Occurrence Measured value ≥ configured upper limit
Recovery Measured value < configured upper limit
Self-retention
(HoLd)
Upper limit
monitoring
Occurrence Measured value ≥ configured upper limit
Retention Measured value < configured upper limit
Recovery Measured value < configured upper limit
Caution: Measured value of pulse count is integrated, so you can reduce it (i.e. clear it to zero) by the preset operation of pulse
count only. For the preset operation of pulse count, page 56.
<Alarm indication at alarm status>
No alarm
Alarm occurrence Alarm retention
When indicating the
alarm-occurrence phase
When indicating
the other phase
When Indicating the
alarm-occurrence phase
When indicating
the other phase
Digital indication Turn ON Flash (*1) Turn ON Flash (*2) Turn ON
Measured element,
Unit, Phase
Turn ON Flash (*1) Flash (*1) Flash (*2) Flash (*2)
*1: Flash (250ms ON / 250ms OFF) *2: Flash (500ms ON / 500ms OFF)