Minarik NRG-2Q Series, User Manual

Page: 29 / 60

Dynamic braking
23 Operation
Dynamic braking may be used to rapidly stop a motor
(Figure 7, page 25). Connect a RUN/BRAKE switch to the
INHIBIT terminals. Connect a dynamic brake resistor to the DB+
and DB- terminals on the printed circuit board. See Figure 3 on
page 13 for dynamic brake resistor connections.
Dynamic brake resistor
The dynamic brake resistor reduces the voltage across the bus
capacitors (C503 and C504) when they reach their maximum
voltage rating. This occurs when the motor regenerates voltage
back to the drive. Bus capacitor maximum voltage ratings are 400
VDC for 240 VAC drives, and 200 VDC for 115 VAC drives.
Dynamic brake resistor value
Use a 40-ohm dynamic brake resistor for models
NRG02-D240AC-2Q and NRG05-D240AC-2Q. Use a 20-ohm
dynamic brake resistor for model NRG10-115AC-2Q. The
dynamic brake resistor tolerance is ± 10%.
Warning
Wait for the motor to completely stop before switching it
back to RUN. This will prevent high armature currents from
damaging the motor or drive.
Inhibit personality header SO503 must be set to BRAKE for
dynamic brake operation. See Figure 7, page 25.
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