Fuji Electric Frenic Mini FRN001C1E-2U, Instruction Manual

Page: 111 / 196

5-30
For three-phase 230 V and single-phase 230 V/115 V class series in-
verters
The limiting level setting for the three-phase 230 V and single-phase 230
V/115 V class series should be calculated from the current limiting level
I
limit
(A) based on the reference current
I
ref
(A), as shown below.
100
(A)
(A)
= (%) Setting
ref
limit
u
I
I
(Example) Setting the current limiting level
I
limit
at 4.2 A for 1HP standard
motors
84 100
(A) 5.0
(A) 4.2
= (%) Setting u
The reference current is given in the table for F20 to F22 on page
5-26.
• The current limiting feature selected by F43 and F44 are implemented
by software, so an operational delay may occur. To avoid the delay,
use the current limiter (hardware) simultaneously (H12 = 1).
• If an overload is applied when the limiting level is set extremely low,
the inverter will immediately lower its output frequency. This may
cause an overvoltage trip or dangerous turnover of the motor rotation
due to undershooting.
If the current limiter function has been activated, the inverter may operate at an ac-
celeration/deceleration time or frequency different from the set ones. The machine
should be so designed that safety is ensured even in any current limiter operation.
Otherwise an accident could occur.
F50, F51
Electronic Thermal Overload Protection for Braking Resistor
(Discharging capability and Allowable average loss)
These function codes specify the electronic thermal overload protection feature for
the braking resistor.
Set the discharging capability and allowable average loss of braking resistors to
F50 and F51, respectively. Those values differ depending upon the specifications of
the braking resistor. Refer to the tables on the next page.
For built-in braking resistors, you may set 0 and 0.000 to F50 and F51, respectively.
Doing so will automatically apply the settings given in the table on the next page.
Refer to the FRENIC-Mini User’s Manual, Chapter 7, Section 7.2 "Selecting a
Baking Resistor" for details.
Depending on the discharging capability margin of a braking resistor, the
electronic thermal function may operate and issue the overheat alarm
FDJ , even if the actual temperature of the resistor is lower than that
specified. Check braking resistor performance again and review the data
setting of function codes F50 and F51.