Baldor MN770 manual

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Gearless Elevator ± An elevator powered by a low speed motor (usually DC) which has the drive sheave mounted directly on the motor shaft. It uses no gearbox. These are used in high speed elevators. Typical motor speeds are 70 -150 RPM at contract speed.

Governor ± A mechanical speed measuring device propelled by a cable suspended from the elevator. As speed increases, centrifugal force causes counterweights to move and signal the controller of a fault condition. Eventually, the brake is activated to stop the elevator movement if a predetermined car speed limit is exceeded.

Hoist way ± The elevator shaft.

Hydraulic Elevator ± An elevator raised and lowered by a hydraulic cylinder. Limited to fairly slow speeds and a low number of stops. Also called a hydro.

Inspection ± The act of visual and functional testing of the elevator. May be performed by contractors or city/state inspectors.

Inspection Speed ± A fixed low speed (about 10 ft/min) used to move the elevator car for inspection purposes. Similar to a jog speed in an industrial application.

Jerk ± Represents the rate of change of acceleration or deceleration during an S±curve.

Leveling ± The act of aligning the elevator car with the floor. Current elevator code requires this to be within ±1/4 inch.

Leveling Field ± On a DC control, the field voltage setting which provides more than rated voltage to over±excite the motor field used during the leveling process.

Leveling Speed ± A fixed low speed used to move the elevator the final two feet allowing precision floor leveling.

M-Contactor± Provides a positive disconnect of the motor from electrical power. Most elevator codes require one or two M-Contactors between the motor and control.

Mechanic ± An electrically operated device that provides a positive disconnect of the motor from the control. Elevator codes vary but most require one or two M-Contactors be installed between the motor and control.

Modernization ± Updating of an old elevator with new drives and controls to meet current codes.

Motor-Generator Set ± On older DC elevators, an AC motor powers a DC generator supplying DC power to operate the DC traction motor. By varying the field excitation of the DC generator, the power supplied to the DC motor may be adjusted. Also known as a Ward±Leonard set.

NAEC ± National Association of Elevator Contractors, the trade organization of contractors, suppliers and consultants for the elevator industry in the US.

NAVTP ± National Association of Vertical Transportation Specialists, the trade organization of elevator consultants. Overhead ± The area above the elevator at the top of the hoist way.

Overhauling Load ± When a load requires more torque than the motor can provide, the motor may exceed the commanded speed. This is an overhauling load. Braking is used to prevent the load (car) from falling. The brake may be mechanical or electrical (dynamic or regenerative). Ultimately a mechanical brake must be set to hold the load in case of a power failure or when the drive is not enabled. Baldor Line Regenerative controls provide reverse torque to hold the load and prevent a run away over speed condition.

C-2 Appendix C

MN770

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Contents MN770 Elevator Application GuideTable of Contents Ii Table of Contents MN770 Modernizations Section General InformationIntroduction Drive DefinitionLimited Warranty Safety Notice VAC or 460 VAC maximum per control rating Perform a ªMeggerº test. Failure to disconnect motor fromUnderwriter Laboratory requirements Drive Performance Comparison FeatureSection Technologies Overview20H 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 SelectionCable Preparation Section Hardware InformationGeneral Considerations Encoder RetrofitEncoder Cables Single Ended Connections Encoder Cable ConnectionDifferential Connections Encoder End Control EndBuffered Encoder Output Feedback Section Set-Up InformationDC SCR Controls Field ControlOverload = Fault Following Error = on Torque Proving = on Final InstallationFinal Adjustments Contactor Armature EnableBrake Release Signal Speed CommandInverter 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 Encoder Circuits Wiring PracticesPower Wiring Analog Signal WiresFiber Optics Optical IsolationPlant Ground Optical CouplersLoad 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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