Baldor ID15J1F50-ER, Инструкция по установке и эксплуатации

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Appendix A
Dynamic Brake Hardware
MN715J Dynamic Brake Hardware A-1
Dynamic Braking (DB) Hardware
Whenever a motor is abruptly stopped or forced to slow down quicker than if
allowed to coast to a stop, the motor becomes a generator. This energy
appears on the DC Bus and must be dissipated using dynamic braking
hardware. Dynamic braking (DB) hardware is a resistive load. Table A-1
provides a matrix of DB turn ON and turn OFF voltages.
Table A-1
Parameter Description Control Input Voltage
Nominal Voltage 115VAC 230VAC 460VAC
Overvoltage Fault
(Voltage exceeded)
400VDC 400VDC 800VDC
DB ON Voltage 381VDC 381VDC 762VDC
DB Upper Tolerance Peak 388VDC 388VDC 776VDC
DB OFF Voltage 375VDC 375VDC 750VDC
Braking torque and time should not exceed the available drive braking torque
and time rating. The drive braking torque is limited to the available peak
current and peak current time rating of the control. If the peak current or peak
current time limit is exceeded during braking, the control may trip on an over
voltage or a regen power fault.
Selection Procedure
1. Calculate the watts to be dissipated using the following formulas for the
appropriate load type.
2. Identify the control model number and determine which braking
hardware is required based on the model number suffix: ER.
3. Select appropriate braking hardware from Baldor 501 Catalog or Table
A-2.
Hoisting Load Calculations
1. Calculate braking duty cycle:
Duty Cycle +
Lowering Time
Total Cycle Time
2. Calculate braking watts to be dissipated in dynamic braking resistors:
Watts
+
duty cycle lbs FPM efficiency
44
where: lbs = weight of load
FPM = Feet Per Minute
efficiency = mechanical efficiency
i.e., 95% = 0.95