Electrical Noise Considerations Continued

Control Enclosures Motor controls mounted in a grounded enclosure should also be connected to earth ground with a separate conductor to ensure best ground connection. Often grounding the control to the grounded metallic enclosure is not sufficient. Usually painted surfaces and seals prevent solid metallic contact between the control and the panel enclosure. Likewise, conduit should never be used as a ground conductor for motor power wires or signal conductors.

Special Motor Considerations Motor frames are also on the required grounding list. As with control enclosures, motors should be grounded directly to the control and plant ground with as short a ground wire as possible. Here's why. Capacitive coupling within the motor windings produces transient voltages between the motor frame and ground. The severity of these voltages increases with the length of the ground wire. Installations with the motor and control mounted on a common frame, and with heavy ground wires less than 10 ft. long, rarely have a problem caused by these motor±generated transient voltages.

Another cure may be needed when the motor frame transient voltages are capacitively coupled to feedback devices mounted on the motor shaft. Especially with optical encoders, these transients create noise on the signal leads and disrupt drive operation.

To prevent this problem, add electrical isolation between the motor and the feedback device to stop the current flow and the resulting transients. The most simple isolation method, shown in Figure 6-10, has two parts: 1) A plate of electrical insulating material placed between the motor mounting surface and the feedback device. 2) An insulating coupling between motor shaft and the shaft of the feedback device.

Figure 6-10 Isolated Mounting Method

Insulating Coupling

Insulating plate

Encoder or other feedback device

Mounting bracket

6-6 Troublehsooting

MN770

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Baldor MN770 manual Isolated Mounting Method
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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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