Fuji Electric FRENIC-HVAC User Manual page 377

F18 Bias (Frequency command 1)
Refer to the description of F01.
F20 to F22 DC Braking 1 (Braking starting frequency, Braking level and Braking time)
H95 DC Braking (Braking response mode)
These function codes specify the DC braking that prevents motor 1 from running by inertia
during decelerate-to-stop operation.
If the motor enters a decelerate-to-stop operation by turning OFF the run command or by
decreasing the reference frequency below the stop frequency, the inverter activates the DC
braking by flowing a current at the braking level (F21) for the braking time (F22) when the
output frequency goes down to the DC braking starting frequency (F20).
Setting the braking time to "OFF" disables the DC braking.
Braking starting frequency (F20)

F20 specifies the frequency at which the DC braking starts its operation during motor
decelerate-to-stop state.
- Data setting range: 0.0 to 60.0 (Hz)
Braking level (F21)

F21 specifies the output current level to be applied when the DC braking is activated. The
function code data should be set, assuming the rated output current of the inverter as 100%, in
increments of 1%.
- Data setting range: 0 to 60 (%)
The inverter rated output current differs between the HD and MD/LD modes.
Braking time (F22)

F22 specifies the braking period that activates DC braking.
- Data setting range: 0.01 to 30.00 (s)
Braking response mode (H95)

H95 specifies the DC braking response mode.
Data for H95
0
1
OFF (Disable)
Characteristics
Slow response. Slows the rising
edge of the current, thereby
preventing reverse rotation at the
start of DC braking.
Quick response. Quickens the rising
edge of the current, thereby
accelerating the build-up of the
braking torque.
6-67
6.3 Details of Function Codes
Refer to F01.
Note
Insufficient braking torque may
result at the start of DC braking.
Reverse rotation may result
depending on the moment of inertia
of the mechanical load and the
coupling mechanism.