Baldor MN770 manual

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Pattern Generator ± An external circuit board used to generate an adjustable S±curve speed command for smooth acceleration and deceleration. This signal is used by the motor control instead of any on±board S±curve. It uses feedback from the elevator by means of a DC tach or encoder.

Pit ± The area below the elevator at the bottom of the hoist way. It usually contains a buffer or other means of stopping the car during emergencies.

Rails ± The steel tracks which guide the elevator in the hoist way.

Rollback ± A condition where the holding brake is released and the elevator car rolls slightly in the hoist way before the control is able to hold it steady prior to moving to the next stop.

Ropes ± The steel cables used to suspend the car and counterweights.

Running Field ± On a DC control, the normal field voltage setting which provides rated field voltage to the motor for most conditions.

Sheave ± A drum mounted on the output shaft of the traction machine gearbox or the armature of a gearless motor on which the cables holding the elevator are wrapped. This rotates to drive the elevator.

Standby Field ± On a DC control, the field voltage setting which provides a reduced field voltage to the motor allowing the field to be continuously energized. It is the same as field economy in industrial applications, usually 67% of rated field voltage.

Stop ± The number of floors in the building where the elevator may be boarded.

Tape ± A punched tape (similar to a NC machine programming tape) which is attached in the hoist way providing actual elevator position to the controller.

Torque Feed Forward ± A control scheme where the elevator weight is sensed and a voltage is provided to the motor control as a trim to eliminate any rollback of the car when the brake is released.

Torque Proving ± After closing the motor contactors, the motor control checks for continuity with the motor before releasing the brake and providing full power to the motor.

Tracking ± The act of the control following the commanded signal.

Traction Elevator ± A geared elevator in which a motor drives either a right angle worm gearbox or an inline gearbox for speed reduction and torque multiplication. ªTractionº comes from the friction of the ropes gripping the sheave and preventing slippage. The ropes usually have a number of turns around the sheave to increase the traction.

Turned Over ± The final step in commissioning the elevator system for normal passenger use. VVVF ± Variable voltage, variable frequency control ± usually an AC inverter.

MN770

Appendix C-3

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Contents Elevator Application Guide MN770Table of Contents Ii Table of Contents MN770 Section General Information IntroductionDrive Definition ModernizationsLimited Warranty Safety Notice Perform a ªMeggerº test. Failure to disconnect motor from VAC or 460 VAC maximum per control ratingUnderwriter Laboratory requirements Feature Section TechnologiesOverview Drive Performance ComparisonDC SCR Control 20H Control15H Control Inverter21H Control 17H & 18H Controls Vector22H Control Section Application Considerations Electric Drives Operating Mode Common Control FeaturesAvailable Operating Modes US Measurement System Elevator Motor Horsepower SelectionMetric Measurement System Motor Sizing Dynamic Brake Hardware Selection OCW =Section Hardware Information General ConsiderationsEncoder Retrofit Cable PreparationEncoder Cables Encoder Cable Connection Differential ConnectionsEncoder End Control End Single Ended ConnectionsBuffered Encoder Output Section Set-Up Information DC SCR ControlsField Control FeedbackFinal Installation Overload = Fault Following Error = on Torque Proving = onFinal Adjustments Armature Enable Brake Release SignalSpeed Command ContactorInitial Installation and Startup Inverter ControlsPage TURN-ON Vector Controls Balanced Car Test Full Load TestFinal Wiring Connections Series 18H Control ConsiderationsProcedure Initial Set-upRated Motor Load Slip Adjustment Value Slip Adjustment ValueFinal Set-up Power Up/Down Sequence for Vector Controls Pre-Installation Tests DateVector Control Worksheet Set-Up Information MN770 Section Troubleshooting Electrical Noise Display R-C Snubber Circuit & twisted-pair Electrical Noise Considerations10HP, 460VAC Drive 30HP, 500VDC Drive, Shielded 10 Isolated Mounting Method Wiring Practices Power WiringAnalog Signal Wires Encoder CircuitsOptical Isolation Plant GroundOptical Couplers Fiber OpticsAppendix a Load Weighing / Torque Feed ForwardTable A-1 Description of OperationAppendix B Serial CommunicationsAppendix B MN770 Appendix C Elevator Industry GlossaryPage Page Appendix C MN770 Box  Baldor Electric Company MN770 97 C&J300

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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