Baldor MN770 manual 30HP, 500VDC Drive, Shielded

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Electrical Noise Considerations Continued

Even input AC power lines contain noise and can induce noise in adjacent wires. This is especially severe with SCR controlled DC drives, current±source and six±step inverters. Figure 6-9 shows a transient induced in 1±ft. wire adjacent to AC input power wire to 20 hp, DC drive. Scope is set at 500 mV/div. and 2msec/div.

Figure 6-9 30HP, 500VDC Drive, Shielded

To prevent induced transient noise in signal wires, all motor leads and AC power lines should be contained in rigid metal conduit, or flexible conduit. Do not place line conductors and load conductors in same conduit. Use separate conduit for 3 phase input wires and motor leads. The conduit should be grounded to form a shield to contain the electrical noise within the conduit path. Signal wires - even ones in shielded cable should never be placed in the conduit with motor power wires.

If flexible conduit is required, the wires should be shielded twisted-pair. Although this practice gives better protection than unshielded wires, it lacks the protection offered by rigid metal conduit.

Special Drive SituationsFor severe noise situations, it may be necessary to reduce transient voltages in the wires to the motor by adding load reactors. Load reactors are installed between the control and motor. These are often required where a motor housing lacks the necessary shielding (typically linear motors mounted directly to machine frames) or where the power wires to motors are contained in flexible cables.

Reactors are typically 3% reactance and are designed for the frequencies encountered in PWM drives. For maximum benefit, the reactors should be mounted in the drive enclosure with short leads between the control and the reactors. Baldor offers a complete line of line and load reactors that will reduce ripple current and improve motor life.

Drive Power Lines The same type of reactor as installed on the load side of the control can also suppress transients on incoming power lines. Connected on the line side of the drive, the reactor protects the adjustable±speed drive from some transients generated by other equipment and suppresses some of the transients produced by the drive itself.

Radio Transmitters Not a common cause of noise, radio frequency transmitters, such as commercial broadcast stations, fixed short±wave stations, and mobile communications equipment (including walkie talkies) create electrical noise. The probability of this noise affecting an adjustable±speed drive increases with the use of open control enclosures, open wiring, and poor grounding.

MN770

Troublehsooting 6-5

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Contents Elevator Application Guide MN770Table of Contents Ii Table of Contents MN770 Drive Definition Section General InformationIntroduction ModernizationsLimited Warranty Safety Notice VAC or 460 VAC maximum per control rating Perform a ªMeggerº test. Failure to disconnect motor fromUnderwriter Laboratory requirements Overview FeatureSection Technologies Drive Performance ComparisonDC SCR Control 20H 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 Dynamic Brake Hardware Selection OCW =Encoder Retrofit Section Hardware InformationGeneral Considerations Cable PreparationEncoder Cables Encoder End Control End Encoder Cable ConnectionDifferential Connections Single Ended ConnectionsBuffered Encoder Output Field Control Section Set-Up InformationDC SCR Controls FeedbackFinal Installation Overload = Fault Following Error = on Torque Proving = onFinal Adjustments Speed Command Armature EnableBrake Release Signal ContactorInitial Installation and Startup Inverter ControlsPage TURN-ON Vector Controls Balanced Car Test Full Load TestFinal Wiring Connections Series 18H Control ConsiderationsProcedure Initial Set-upSlip Adjustment Value Rated Motor Load 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 Analog Signal Wires Wiring PracticesPower Wiring Encoder CircuitsOptical Couplers Optical IsolationPlant Ground 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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