E6582233
F-29
6
6.13.4 Dynamic (regenerative) braking - For abrupt motor stop
f304
: Dynamic braking selection
f308
: Dynamic braking resistance
f309
: Dynamic braking resistor capacity
f626
: Over-voltage stall protection level
Function
VFNC3E-4004P,4007P models don’t have the PA/+ and PB terminals and cannot be used with the
braking resistor.
The inverter does not contain a braking resistor. Connect an external braking resistor in the following
cases to enable dynamic braking function:
1) when decelerating the motor abruptly or if overvoltage tripping (
op
) occurs during deceleration
stop
2) when a continuous regenerative status occurs during downward movement of a lift or the winding-
out operation of a tension control machine
3) when the load fluctuates and a continuous regenerative status results even during constant speed
operation of a machine such as a press
[Parameter setting]
Title Function
Adjustment range
Default setting
f304
Dynamic braking selection
0: Disabled
1: Enabled, Resistor overload
protection enabled
2: Enabled
3: Enabled, Resistor overload
protection enabled
(At ST terminal on)
4: Enabled (At ST terminal on)
0
f308
Dynamic braking resistance
1.0-1000 (
)
Depending on
models
(See Section 10.4)
f309
Dynamic braking resistor
capacity
0.01-30.00 (kW)
f626
Over-voltage stall protection
level
100-150 (%) *1
136
*1: 100% corresponds to an input voltage of 400V for 400V models.
★
Assigning the braking resistor overload pre-alarm (function number : 30,31) to any logic output terminal,
overload status of braking resistor can be output.
Note 1) The operation level of dynamic braking is defined by parameter
f626
.
Note 2) If parameter
f304
=1 to 4, the inverter will be set automatically so as to deal with the regenerative
energy from the motor by means of a resistor, without taking any action to limit overvoltage. (The
same function as
f305
=1)