Mitsubishi Electric fr-e700 series, Instruction Manual

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Parameter Special operation
FR-E700 SC EC/ENE 6 - 315
What is regeneration avoidance function? (Pr. 882, Pr. 883)
When the regeneration status is serious, the DC bus voltage rises and an overvoltage alarm (E.OV
첸
)
may occur. When this bus voltage rise is detected and the bus voltage level reaches or exceeds Pr. 883,
increasing the frequency avoids the regeneration status.
The regeneration avoidance function is always on when "1" is set in Pr. 882 and activated only during
a constant speed when "2" is set in Pr. 882.
I001257E
Fig. 6-163: Regeneration avoidance function
NOTES
The inclination of the frequency increased or decreased by the regeneration avoidance function
changes depending on the regeneration status.
The DC bus voltage of the inverter is normally about
冑
2 times greater than the input voltage (when
the input voltage is 220 V, the bus voltage is about 311 V DC and when the input voltage is 440 V
AC, the bus voltage is about 622 V DC). However, it varies with the input power supply waveform.
The Pr. 883 setting should be kept higher than the DC bus voltage level. Otherwise, the regenera-
tion avoidance function is always on.
While overvoltage stall (oL) stops the output frequency during deceleration, the regeneration
avoidance function is always on and increases the frequency according to the regeneration
amount.
Bus v
oltage
[V DC
]
Output
fr
equenc
y [H
z]
Regeneration avoidance operation
example for acceleration Regeneration avoidance operation
example for constant speed Regeneration avoidance operation
example for deceleration
Pr. 883
Pr. 883
Pr. 883
During regeneration avoidance function
operation
During regeneration avoidance
function operation
During regeneration avoidance
function operation
Time
Time
Time
Bus v
oltage
[V DC
]
Output
fr
equenc
y [H
z]
Bus v
oltage
[V DC
]
Output
fr
equenc
y [H
z]