Baldor MN770 manual DC SCR Control, 20H Control

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DC SCR Control

NEMA Type C designation of electrical power source equipment for adjustable speed

 

drives.

 

Series 19H DC SCR (not used in elevator applications)

 

Series 20H DC SCR (Line Regenerative)

 

DC SCR controls are used in elevator applications where speeds range from 50 to over

 

1000 FPM. The Baldor DC SCR (Thyristor) control is a three phase, full wave rectified,

 

DC motor armature and field (where applicable) control. The SCR bridge converts three

 

phase AC to DC power. This rectified DC provides power to the DC motor armature, and

 

the reference transformer to operate power supplies and other circuits.

 

Armature or encoder feedback may be used with either control. DC tachometer or

 

resolver feedback is available with the optional expansion board. A Series 20H control

 

can be configured to check for torque output (torque proving) before a holding brake is

 

released.

20H Control

The Series 20H is a standard line regenerative control. Regenerated power is applied

 

back to the incoming power lines. External filters can improve the Total Harmonic

 

Distortion (THD) of the AC waveform. This control is not designed for regenerative use

 

with stabilized shunt or compound wound DC motors. If stabilized shunt or compound

 

wound motors are to be used, the series field must be isolated and not connected.

 

Contact the motor manufacturer for motor derating under these conditions.

 

Regulation from the Series 20H, using armature feedback, will be 2% of base speed.

 

With DC tachometer feedback, the regulation will be 1% of set speed. Use of encoder or

 

resolver feedback will provide 0.1% regulation.

2-2 Technologies

MN770

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Contents MN770 Elevator Application GuideTable of Contents Ii Table of Contents MN770 Introduction Section General InformationDrive Definition ModernizationsLimited Warranty Safety Notice VAC or 460 VAC maximum per control rating Perform a ªMeggerº test. Failure to disconnect motor fromUnderwriter Laboratory requirements Section Technologies FeatureOverview Drive Performance Comparison20H Control DC SCR ControlInverter 15H Control21H Control Vector 17H & 18H Controls22H Control Section Application Considerations Electric Drives Common Control Features Operating ModeAvailable Operating Modes Elevator Motor Horsepower Selection US Measurement SystemMetric Measurement System Motor Sizing OCW = Dynamic Brake Hardware SelectionGeneral Considerations Section Hardware InformationEncoder Retrofit Cable PreparationEncoder Cables Differential Connections Encoder Cable ConnectionEncoder End Control End Single Ended ConnectionsBuffered Encoder Output DC SCR Controls Section Set-Up InformationField Control FeedbackOverload = Fault Following Error = on Torque Proving = on Final InstallationFinal Adjustments Brake Release Signal Armature EnableSpeed Command ContactorInverter Controls Initial Installation and StartupPage TURN-ON Vector Controls Full Load Test Balanced Car TestSeries 18H Control Considerations Final Wiring ConnectionsInitial Set-up ProcedureSlip Adjustment Value Rated Motor Load Slip Adjustment ValueFinal Set-up Power Up/Down Sequence for Vector Controls Date Pre-Installation TestsVector Control Worksheet Set-Up Information MN770 Section Troubleshooting Electrical Noise Display Electrical Noise Considerations R-C Snubber Circuit & twisted-pair10HP, 460VAC Drive 30HP, 500VDC Drive, Shielded 10 Isolated Mounting Method Power Wiring Wiring PracticesAnalog Signal Wires Encoder CircuitsPlant Ground Optical IsolationOptical Couplers Fiber OpticsLoad Weighing / Torque Feed Forward Appendix aDescription of Operation Table A-1Serial Communications Appendix BAppendix B MN770 Elevator Industry Glossary Appendix CPage Page Appendix C MN770  Baldor Electric Company MN770 97 C&J300 Box

MN770 specifications

The Baldor MN770 is an impressive industrial motor designed for a variety of applications, showcasing robust construction and advanced technology. Known for its reliability and efficiency, the MN770 is manufactured by Baldor Electric Company, a prominent name in the electric motor industry.

One of the main features of the MN770 is its high-efficiency design. This motor adheres to stringent efficiency standards, helping to reduce energy consumption and lower operational costs. It typically meets or exceeds NEMA Premium Efficiency ratings, making it an excellent choice for businesses looking to optimize their energy use.

The MN770 motor is built with a durable cast iron frame, ensuring longevity and resistance to harsh operating conditions. Its weatherproof design is ideal for both indoor and outdoor applications, making it suitable for various environments, including manufacturing plants, water treatment facilities, and agricultural operations.

Another significant characteristic of the MN770 is its versatility. The motor is available in a range of horsepower ratings, allowing users to select the model that best fits their specific needs. Additionally, it offers various mounting configurations and voltage options, further enhancing its adaptability for diverse applications.

The motor utilizes advanced insulation systems and cooling technologies to ensure optimal performance and a longer lifespan. The robust design helps to dissipate heat effectively, enabling the motor to operate efficiently even under heavy loads. This characteristic is essential for applications requiring continuous operation without compromising reliability.

Moreover, the Baldor MN770 incorporates advanced design features such as precision-balanced rotors and high-performance bearings. These characteristics contribute to reduced vibration and noise levels, promoting a quieter working environment and improving overall operation efficiency.

In summary, the Baldor MN770 motor stands out due to its high efficiency, robust construction, versatility, and advanced technologies. Its ability to perform reliably in various industrial applications makes it a popular choice among engineers and facility managers. Investing in the MN770 not only enhances operational efficiency but also supports sustainability efforts by reducing energy consumption in industrial environments.
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