Minarik NRG-2Q Series, User Manual, Page: 30 / 60

24 Operation
DBwatts = (Motor Power watts X duty cycle) X 1.2
= [(Horsepower X 746) X duty cycle] X 1.2
duty cycle =
TREGEN
TREGEN
where TREGEN is the amount of time the motor is generating
voltage back into the drive, and TMOTOR is the amount of time
the drive is generating voltage into the motor. The absolute
minimum dynamic brake resistor power rating is typically 100
watts.
Example:
Size a DB resistor for a 1 HP motor that has a 50% duty cycle. It
will be used with model NRG05–D240AC–2Q.
Solution:
Use a 40 ohm resistor with a minimum power rating of at least
448 watts.
Dynamic brake resistor power rating
Use the following equation to determine the dynamic brake
resistor power rating:
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