9.2 Details of Function Codes
9-23
Chap. 9 FUNCTION CODES
In the above expressions, it is assumed that each function code expresses its data.
Example:
Setting the bias, gain and its reference point when analog input range from 1 to 5
VDC is selected for the frequency command 1
(Point A)
If the analog input is at 1 V, the set frequency is 0 Hz. Therefore, the bias is 0% (F18 = 0). Since
1 V is the bias reference point and it is equal to 10% of 10 V, then the bias reference point
should be 10% (C50 = 10).
(Point B)
If the analog input is at 5 V, the set frequency comes to be the maximum value. Therefore, the
gain is 100% (C32 = 100). Since 5 V is the gain reference point and it is equal to 50% of 10 V,
then the gain reference point should be 50% (C34 = 50).
When using the function codes for setting a stand alone gain or bias without
changing any reference points, the setting procedure for the function codes is the
same as that of Fuji conventional inverter models.
F20 DC Braking (Start frequency)
F21 DC Braking (Braking level) Refer to H95.
F22 DC Braking (Braking time)
These function codes specify the parameters for DC braking, a mechanism to pre-vent the
motor from coasting due to the inertia of moving loads while it is decelerating to a stop. During
a decelerated stop cycle, i.e., when any Run command "OFF" has been issued or the set
frequency has dropped below the stop frequency, DC braking is invoked as soon as the output
frequency has reached the start frequency (F20) for DC braking.
Set function codes F20 for the start frequency, F21 for the braking level, and F22 for the
braking time. Optionally, you can also select the quick-response DC braking with H95.
Start frequency (F20)㩷
Set the frequency with which to start DC braking.
- Data setting range: 0.0 to 60.0 (Hz)
Set function code F20 to a frequency that approximately equals the
slip-compensated frequency of the motor. If you set it to an extremely high
frequency, the inverter will be unstable, and in some cases the overvoltage
protective function may work.
Braking level (F21)㩷
Set the output current level to be applied when DC braking is activated. Set the function code
data, assuming the rated output current of the inverter as 100% with 1-% resolution.
- Data setting range: 0 to 100%
Braking period (F22)㩷
Set the braking period during which DC braking is activated.
- Data setting range: 0.00 to 30.00 (sec.)
(Note that setting 0.00 disables DC braking.)
To Next Page
Loading...
