Braking Resistances - Eaton PowerXL DC1 20 Series Installation Manual

6.9 Braking resistances

Figure 86: Examples of DX-BR... brake resistor designs
NOTICE
The specified minimum resistance R
below.
CAUTION

Brake resistors get extremely hot during operation!
The following tables provide examples of DX-BR... brake resistors rated for
individual DC1 variable frequency drives. They are specified based on the
"high duty" and "low duty" classification for intermittent braking with a cycle
time t of 120 seconds and a pulse power P
C
power P of the variable frequency drive with the rated motor output.
max
Load groups (simplified classification)
• Low duty: Low load with short braking duration and low duty factor
(up to about 25 %), e.g., for horizontal conveyors and handling
equipment for bulk cargo and general cargo, end carriages, sliding doors,
and turbomachinery (centrifugal pumps, fans).
• High duty: High load with long braking duration and high duty factor
(at least 30 %), e.g., for elevators, downhill conveyors, winders,
centrifuges, flywheel motors, and large fans.
DC1...20... and DC1...OE1 Variable Frequency Drives 02/20 MN040059EN www.eaton.com
6 Technical Data
6.9 Braking resistances
must not be fallen
Bmin
equal to maximum braking
Peak
173