Danfoss VLT 6002-6011 Installation, Operation And Maintenance Manual

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Danfoss VLT 6002-6011 Installation, Operation And Maintenance Manual Manual pdf 38 page image

38DC BrakingApplying DC current to the motor will brake the motor. Parameter 114,DC Braking Current, sets the DC braking current as a percentage ofthe rated motor current. Parameter 115, DC Braking Time, sets theamount of time that the DC current will be applied. Parameter 116, DCBrake Cut-in Frequency, sets the frequency at which DC brakingbegins when the motor decelerates during a stop.If terminal 19 or 27 (parameters 303 or 304 Digital Input) has beenprogrammed to DC Braking Inverse and shifts from logic ‘1’ to logic ‘0’,the DC braking will be activated immediately.When the start signal on terminal 18 changes from logic ‘1’ to logic ‘0’,the DC braking will be activated when the output frequency becomeslower than the brake cut-in frequency.If a DC brake current is set in parameter 114, the drive’s switchingfrequency will be limited to 4 kHz during the braking.WARNING!A high braking current supplied for a long timewill overheat motor. Use only the DC brakingcurrent and time required.CAUTION!Do not use DC braking function if inertia ofdriven load is more than 20 times inertia ofmotor.114 DC Braking Current (DC BRAKE CURRENT)Value:0 to 100% 50 %The maximum value depends on the rated motor current.Function:This parameter is used for setting the DC braking current that isapplied:1. When the DC brake frequency set in parameter 116 DC BrakeCut-in Frequency has been reached during a stop.2. When DC brake inverse is active via terminal 19 or 27, or via theserial bus.The DC braking current will be active for the duration of the DCbraking time set in parameter 115 DC Braking Time.Description of choice:To be set as a percentage value of the rated motor current set inparameter 105 Motor Current.100% DC braking current corresponds to the value set in parameter105.115 DC Braking Time (DC BRAKE TIME)Value:0.0 to 60.0 sec. ✭ 10.0 sec.Function:This parameter sets the time that the DC braking is active.Description of choice:Set the desired time.116 DC Brake Cut-in Frequency(DC BRAKE CUT-IN)Value:0.0 (OFF) to setting of parameter 202 ✭ OFFFunction:This parameter is used for setting the frequency at which DC brakingbegins after a stop command is issued.Description of choice:Set the desired frequency for braking to begin upon deceleration.CAUTION!Most HVAC applications do not required brak-ing or holding. It is suggested that parameter114 remains set at 0 unless unusual applica-tion requirements call for braking or holdingtorque.✭ Indicates default parameter. Depending upon the application, the drive may be delivered with other parameters selected.