Operational manual for dynamic braking unit
-17-
Crane(the height of lifting is more than 100m) K
f
=20-40%
Occasionally braking load K
f
=5%
Others K
f
=10%
Basis of resistor calculation: the braking resistor needs to absorb all the regenerative electric
energy of the motor.
Absorbed power of the resistor(V*V/R)=The regenerative electric energy of the motor (W)=
1000*P*
Basis of resistor power calculation:
The regenerative electric energy of the motor needs to be absorbed by the resistor and
converted into heat to release.
P
R
=P* K
f
*
*
=P* K
f
*1.0*1.4
8.4 Usage standard and selection reference of the input voltage degree
for adaptation DBU (220V)
Below is the selection reference when the DC operating point of the braking unit is 380V:
100% of the
adaptation
braking
resistor of
the braking
torque(Ω)
Dissipated
power of the
braking
resistor(kW)
(10% of the
braking)
Dissipated
power of the
braking
resistor(kW)
(50% of the
braking)
Dissipated
power of the
braking
resistor(kW)
(80% of the
braking)
Mini
allowable
braking
resistor(Ω)
8.5 Usage standard and selection reference of the input voltage degree
for adaptation DBU (380V)
Below is the selection reference when the DC operating point of the braking unit is 700V: