Honeywell NXL Series Applications Manual page 35

Honeywell
Par. 2.1.9 = 1 (Stop function = Ramp):
After the Stop command, the speed of the
motor is reduced according to the set
deceleration parameters, as fast as
possible, to the speed defined with
parameter 2.4.5, where the DC-braking
starts.
The braking time is defined with
parameter 2.4.4. If high inertia exists, it is
recommended to use an external braking
resistor for faster deceleration. See Figure
1- 12.
2.4.5 DC-braking frequency in ramp stop
The output frequency at which the DC-braking is applied. See Figure 1- 12.
2.4.6 DC-braking time at start
DC-brake is activated when the start command
is given. This parameter defines the time
before the brake is released. After the brake is
released, the output frequency increases
according to the set start function by parameter
2.1.8. See Figure 1- 13.
2.4.7 Flux brake
Instead of DC braking, flux braking is a useful form of braking with motors ≤15kW.
When braking is needed, the frequency is reduced and the flux in the motor is increased, which
in turn increases the motor's capability to brake. Unlike DC braking, the motor speed remains
controlled during braking
The flux braking can be set ON or OFF.
0 = Flux braking OFF
1 = Flux braking ON
Note: Flux braking converts the energy into heat at the motor, and should be used
intermittently to avoid motor damage
Description of parameters
Figure 1- 12. DC-braking time when Stop mode =
Ramp
Figure 1- 13. DC braking time at start
f out
Motor speed
Output frequency
par. 2.4.5
RUN
STOP
Output
frequency
Par 2.4.6
RUN
STOP
Page 35 (68)
DC-braking
t
t = Par. 2.4.4
NX12K23
t
NX12K80
4