Regeneration Avoidance Function - Mitsubishi Electric FR-CS82S-025 Instruction Manual

Parameters referred to
Pr.7 Acceleration time, Pr.8 Deceleration time
page 99
Pr.13 Starting frequency
Pr.75 Reset selection/disconnected PU detection/PU stop selection
Pr.261 Power failure stop selection
Pr.502 Stop mode selection at communication error

5.12.7 Regeneration avoidance function

The regenerative status can be detected and avoided by raising the frequency.
• The operation frequency is automatically increased to prevent the regenerative operations. This function is useful when a
load is forcibly rotated by another fan in the duct.
Pr. Name
Regeneration
882
avoidance operation
G120
selection
Regeneration
883
avoidance operation
G121
level
Regeneration
885 avoidance
G123 compensation
frequency limit value
886 Regeneration
G124 avoidance voltage gain
Regeneration
665
avoidance frequency
G125
gain
 Regeneration avoidance operation (Pr.882, Pr.883)
• When the regenerative voltage increases, the DC bus voltage will rise, which may cause an overvoltage fault (E.OV[]). The
regenerative status can be avoided by detecting this rise of bus voltage, and raising the frequency when the bus voltage
level exceeds
Pr.883 Regeneration avoidance operation level
• The regeneration avoidance operation can be selected to operate constantly or operate only during constant speed.
• The regeneration avoidance function is enabled by setting "1 or 2" in
Regeneration avoidance operation
example for acceleration
Pr.883
During regeneration
avoidance function operation
NOTE
• The slope of frequency rising or lowering by the regeneration avoidance operation will change depending on the regenerative
status.
• The DC bus voltage of the inverter will be approximately
The bus voltage is about 311 VDC (622 VDC) when the input voltage is 220 VAC (440 VAC). However, it may vary depending
on the input power supply waveform.
page 93
page 85
page 160
page 165
Setting
Initial value
0
1
0
2
200 V
400 VDC
class
300 to 800 V
400 V
780 VDC
class
0 to 10 Hz
6 Hz
9999
100% 0 to 200%
100% 0 to 200%
Regeneration avoidance operation
example for constant speed
Pr.883
Time
During regeneration
avoidance function operation
Time
range
The regeneration avoidance function is disabled.
The regeneration avoidance function is always enabled.
The regeneration avoidance function is enabled only during
constant-speed operation.
Set the bus voltage level to operate the regeneration avoidance
operation. When the bus voltage level is set low, it will be harder
to generate overvoltage error, but actual deceleration time will
be longer.
Set the setting value higher than the (power supply voltage ×
√
) value.
2
Set the limit value for frequency to rise when the regeneration
avoidance function is activated.
The frequency limit is disabled.
Adjust the response during the regeneration avoidance
operation. Increasing the setting improves the response to
change in the bus voltage. However, the output frequency may
become unstable. If setting a smaller value in Pr.886 does not
suppress the vibration, set a smaller value in Pr.665.
.
Pr.882 Regeneration avoidance operation selection
Time
Time
√
times of the normal input voltage.
2
Description
Regeneration avoidance operation
example for deceleration
Pr.883
During regeneration
avoidance function operation Time
5. PARAMETERS
5.12 (G) Control parameters
2
2
3
4
5
6
7
8
9
10
.
Time
199