Honeywell HVAC232 Series, Applications Manual

Page: 115 / 145

Application manual HVAC232/402 | Document 27-652 | Issue ENG06 | 2019-08-07 115
Stop DC current time
Determines if braking is ON or OFF and the braking time of the DC-brake
when the motor is stopping. The function of the DC-brake depends on the
stop function, par. 2.3.
0 =
DC brake is not active
>0 =
DC brake is active and its function depends on the Stop function, (par. 2.3).
The DC braking time is determined with this parameter.
Par. 2.3 = 0 (Stop function = Coasting):
After the stop command, the motor coasts to a stop without control from
the frequency converter.
With the DC injection, the motor can be electrically stopped in the shortest
possible time, without using an optional external braking resistor.
The braking time is scaled by the frequency when the DC-braking starts. If
the frequency is greater, or equal to the nominal frequency of the motor, the
set value of parameter 4.10 determines the braking time. When the frequen-
cy is 10% of the nominal, the braking time is 10% of the set value of param-
eter 4.10.
fn
t
t
fn
Output frequency
Motor speed
DC-braking ON
RUN
STOP
RUN
STOP
Output frequency
Motor speed
DC-braking ON
fout
fout
t = 1 × par. 4.10 t = 0.1 × par. 4.10
0.1 × fn
Fig. 53. DC-braking time when Stop mode = Coasting
Par. 2.3 = 1 (Stop function = Ramp):
After the Stop command, the speed of the motor is reduced according to the
set deceleration parameters, if the inertia of the motor and load allows that,
to the speed defined with parameter 4.11, where the DC-braking starts.
The braking time is defined with parameter 4.10. See „Fig. 51. The change of
motor potentiometers reference“ on page 113.
Par 4.9
t
RUN
STOP
Motor speed
Output frequency
DC-braking
fout
t = par. 4.10
Fig. 54. DC-braking time when Stop mode = Ramp
Stop DC current frequency if stop function is ramping
It is the output frequency at which the DC-braking is applied. See picture
above.