Braking Resistors - Eaton PowerXL DA1 Series Installation Manual

6.9 Braking resistors

Figure 104:Examples of DX-BR... braking resistor designs
WARNING
The resistor value must not be less than the specified minimum
resistance R
CAUTION

Braking resistors get extremely hot during operation!
The following tables provide examples of DX-BR... braking resistors rated for
individual DA1 variable frequency drives. They are specified according to the
"High duty" and "Low duty" classification, for intermittent braking, with a
cycle time t of 120 seconds, corresponding to a pulse power P
C
corresponds to the maximum braking output P
drive with the rated motor output.
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.
DA1 Variable Frequency Drives 08/18 MN04020005Z-EN www.eaton.com
Bmin
6 Specifications
6.9 Braking resistors
Peak
of the variable frequency
max
, which
183