Appendix A

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 can be a resistor or transistor 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

230VAC

 

460VAC

 

575VAC

 

 

 

 

 

 

Overvoltage Fault (Voltage exceeded)

400VDC

 

800VDC

 

992VDC

 

 

 

 

 

 

DB ON Voltage

381VDC

 

762VDC

 

952VDC

 

 

 

 

 

 

DB UTP *

388VDC

 

776VDC

 

970VDC

 

 

 

 

 

 

DB OFF Voltage

375VDC

 

750VDC

 

940VDC

 

 

 

 

 

 

*DBUTP (DB Upper Tolerance Peak) + 1.02 x ￿2 x VL*L

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. Selecting an oversized control or a line regenerative control should be considered in these cases.

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: E, EO, ER, MO or MR.

3.Select appropriate braking hardware from Baldor 501 Catalog or Tables A-2, A-3 and A-4.

Hoisting Load Calculations

1.Calculate braking duty cycle:

Lowering Time

Duty Cycle + Total Cycle Time

2.Calculate braking watts to be dissipated in dynamic braking resistors:

duty cycle lbs FPM efficiency

Watts +

44

where: lbs = weight of load FPM = Feet Per Minute efficiency = mechanical efficiency

i.e., 95% = 0.95

MN715

Appendix A-1

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Baldor 15H manual Dynamic Braking DB Hardware, Table A-1, Parameter Description Control Input Voltage, Selection Procedure
Page 107 Page 109

Inverter Control, 15H specifications

The Baldor 15H Inverter Control stands out as a leading solution in the realm of variable frequency drives (VFDs), specifically designed for enhancing motor efficiency and performance in industrial applications. This control unit is engineered to provide robust and reliable performance while ensuring seamless integration with various motor types.

One of the main features of the Baldor 15H is its advanced control algorithms, which facilitate precise motor control. This technology allows for smooth acceleration and deceleration, reducing mechanical stress on the system and extending the lifespan of both the motor and connected equipment. The inverter control is adept at handling both synchronous and asynchronous motors, making it highly versatile for different operational needs.

The Baldor 15H incorporates a user-friendly interface that provides operators with real-time data and diagnostics. This feature allows for easy monitoring and troubleshooting, helping to minimize downtime and maintenance costs. The intuitive control panel simplifies parameter adjustments, enabling quick customization for specific application requirements.

Safety is paramount in industrial environments, and the Baldor 15H includes several safety features designed to protect both the equipment and personnel. These features include overload protection, overvoltage protection, and short-circuit protection, ensuring reliable operation even under demanding conditions.

Energy efficiency is another critical aspect of the Baldor 15H. By utilizing pulse-width modulation (PWM) technology, it optimizes power usage, which translates to lower energy costs and reduced environmental impact. This makes it an excellent choice for companies aiming to improve their sustainability practices.

Moreover, the Baldor 15H supports a variety of communication protocols, allowing for easy integration into existing automation systems. This capability ensures that operators can utilize the inverter control within modern industrial networks, enhancing overall system efficiency.

In terms of physical characteristics, the Baldor 15H is designed for durability and reliability. It comes with a robust enclosure that protects against dust, moisture, and other environmental factors commonly found in industrial settings. Its compact design also allows for easy installation in limited spaces.

Overall, the Baldor 15H Inverter Control is a comprehensive solution that combines advanced technology, safety features, and energy efficiency, making it a preferred choice for industries looking to optimize their motor control systems. Its adaptability to different motor types and integration capabilities further solidify its position as a leader in VFD technology.
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