Fuji Electric FRENIC MEGA G2 Series - Page 422

5.3 Description of Function Codes 5.3.5 H codes (High performance functions)
5-238
 Anti-regenerative control (Operation level) (H114)
Allows the adjustment of the level when anti-regenerative control by torque limiter is performed with H69 = 2, 4.
Basically, there is no need to modify the setting.
H114 data
Function
0.0 to 50.0 %
Adjusted level: Increasing the value increases the frequency operation.
999
Standard operation level (factory default)
• The deceleration time may be automatically increased by anti-regenerative control.
• Disable the anti-regenerative control when a braking unit is connected. Otherwise, the anti-
regenerative control may be activated at the same time as the operation of the braking unit, resulting
in a deceleration time not in accordance with the setting.
• An excessively short deceleration time causes the DC link bus voltage of the inverter to rise too fast
for the anti-regenerative control to function. In that case, specify a longer deceleration time.
H70
Overload prevention control
Specifies the rate of decrease of the output frequency of overload prevention control. Before the inverter generates
a heat sink overheat or overload trip (alarm 0H1 or 0LU ), the output frequency of the inverter is decreased for
avoiding a trip. This is applied when operation is required to continue in a system in which the load decreases as
the output frequency decreases, such as a pump.
H70 data
Function
0.00
Uses the deceleration time currently selected (F08, E11, E13, E15, etc.)
0.01 to 100.0
Decelerates at a deceleration rate of 0.01 to 100.0 (Hz/s).
999
Cancel overload prevention control
 Performing overload prevention control “OLP” (Function code E20 to E24, E27, data = 36)
Outputs “OLP”, which is a signal that turns ON during overload prevention control, in order to inform that the
overload prevention control has been activated and the output frequency has changed.
No effect can be expected in a system in which the load does not decrease even if the output frequency
decreases. Do not use this function.
H71
d90
Deceleration characteristic (forced brake)
Magnetic flux level during deceleration (rate of voltage increase)
When the motor is decelerating, if regenerative energy which exceeds that which the inverter is capable of
processing, intermediate DC voltage will rise, and an overvoltage trip will occur. By setting this function code to 1
or 2, a higher output voltage than the command value is output when decelerating, motor loss is increased, and
regenerative energy is consumed by the motor, allowing deceleration torque to be increased.
If H71 = 1, the rate of voltage increase can be adjusted with d90. If H71 = 2, output voltage is set proportional to
the intermediate DC voltage (F05 = 0: same as disabling AVR) only when decelerating.
H71 data
Function
0
Disable
1
Forced brake operation (rate of voltage increase is adjusted with d90)
2
Forced brake operation (output voltage proportional to intermediate DC voltage:
AVR disabled)