Fuji Electric Frenic lift, Reference Manual

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F44 Current Limiter (Level)
F44 specifies the activation level of the current limiter.
When the output current of the inverter exceeds the level specified by F44, the current limiter works
to manage the output current and reduce the motor torque.
When the output current drops below the level specified by F44, the inverter returns to the normal
operation.
- Data setting range: 100 to 230 (%) (Percentage to the rated current of the inverter)
Auto (The maximum current of each inverter automatically applies.)
Since the current limit operation with F44 is performed by software, it may cause a delay
in control.
F50 to F52 Electronic thermal overload protection for braking resistor
(Discharging capability, Allowable average loss and Braking resistance value)
These function codes specify the electronic thermal overload protection feature for the braking
resistor.
Set the discharging capability, allowable average loss and resistance to F50, F51 and F52,
respectively. These values are determined by the inverter and braking resistor models.
Default setting of these parameters might not be suitable for your braking resistor therefore, before
using this function ask for the correct data to your braking resistors supplier.
Depending on the thermal characteristics of the braking resistor, the electronic thermal
overload protection feature may act so that the inverter issues the overheat protection
alarm dbH even if the actual temperature rise is not large enough. If this happens, review
the relationship between the performance index of the braking resistor and settings of
related function codes.
Calculating the discharging capability and allowable average loss of the braking resistor and configuring the
function code data
Ask to the resistor manufacturer about the resistor rating and then configure the related function
codes.
In lift applications the braking load is constant (vertical load). Use Expressions (1) and (2) given
below.
<Applying braking load during deceleration> <Applying braking load during running at a constant speed>
Braking load (kW)
(Braking time)
Braking load (kW)
(Braking time)
2-48