Maintenance

Table 3: High-potential test voltages

Rated maximum-

Rated power-

Field-test voltage

voltage

frequency withstand

 

 

kV (rms)

kV (rms)

kV (rms)

kV dc

 

 

 

 

38.0

80

60

85

*Megger is a registered trademark of Megger Group, Ltd.

Vacuum-integrity test procedure

1.Observe safety precautions listed in the DANGER and WARNING advisories. Construct the proper barrier and warning light system.

2.Ground the frame of the circuit breaker, and ground each pole not under test.

3.Apply test voltage across each pole for one minute (circuit breaker OPEN).

4.If the pole sustains the test voltage for that period, its vacuum integrity has been verified.

Note: This test includes not only the vacuum interrupter, but also the other insulation components in parallel with the vacuum interrupter. These include the standoff insulators and the insulated drive- links, as well as the insulating (tension) struts between the upper and lower vacuum-interrupter supports. If these insulation components are contaminated or defective, the test voltage will not be sustained. If so, clean or replace the affected components, and retest.

As-found insulation and contact- resistance tests

As-found tests verify the integrity of the circuit-breaker insulation system. Megger* or insulation-resistance tests conducted on equipment prior to installation provide a basis of future comparison to detect changes in the protection afforded by the insulation system. A permanent record of periodic as-found tests enables the maintenance organization to determine when corrective actions are required by watching for significant deterioration in insulation resistance, or increases in contact resistance.

Insulation and contact-resistance test equipment

In addition to the high-potential test equipment capable of test voltages as listed in Table 3, the following equipment is required:

AC high-potential tester with test voltage of 1,500 volts, 60 Hz

Test equipment for contact-resistance tests.

Insulation and contact-resistance test procedure

1.Observe safety precaution listed in the DANGER and WARNING advisories for the vacuum-integrity check tests.

2.Close the circuit breaker. Ground the frame of the circuit breaker, and ground each pole not under test. Use manual charging, closing and tripping procedures.

3.Apply the proper ac or dc high- potential test voltage as shown in Table 3 between a primary conductor of the pole and ground for one minute.

4.If no disruptive discharge occurs, the insulation system is satisfactory.

5.After test, ground both ends and the center metal section of each vacuum interrupter to dissipate any static charge.

6.Disconnect the leads to the spring- charging motor.

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Siemens 38-3AH3 38 kV instruction manual Field-test voltage, Voltage Frequency withstand
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38-3AH3 38 kV specifications

The Siemens 38-3AH3 is a high-voltage circuit breaker designed for medium voltage applications, particularly in substations and industrial environments. This device operates at a voltage level of 38 kV, showcasing Siemens' commitment to innovation and reliability in electrical engineering.

One of the main features of the Siemens 38-3AH3 is its advanced interruption technology, which employs the proven hybrid design combining both gas-insulated and air-insulated technologies. This hybrid approach not only enhances the breaker's performance and reliability but also minimizes its footprint, making it an ideal choice for space-constrained environments.

The Siemens 38-3AH3 uses vacuum interruption technology, allowing for efficient switching with minimal wear and tear. The vacuum interrupters are highly reliable and provide excellent performance under various operating conditions. This technology ensures that the circuit breaker can handle short circuits and overloads effectively, thus protecting the entire electrical system.

Additionally, the Siemens 38-3AH3 incorporates intelligent monitoring systems. These digital technologies provide real-time data on breaker status, operational performance, and maintenance needs. This predictive maintenance capability helps operators to identify potential issues before they develop into significant problems, ultimately leading to reduced downtime and maintenance costs.

Another notable characteristic of the Siemens 38-3AH3 is its high insulation strength. Thanks to its robust design and development, this circuit breaker can withstand adverse environmental conditions, making it suitable for use in diverse geographical locations and climates. Its components are designed to resist contamination and corrosion, ensuring long-term reliability.

The Siemens 38-3AH3 also offers enhanced safety features. It includes protective relays and automatic fault detection systems that isolate faults quickly, preventing damage to downstream equipment. Furthermore, the design allows for easy maintenance, with components that are accessible without the need for extensive disassembly.

In summary, the Siemens 38-3AH3 38 kV circuit breaker is a leading solution in high-voltage protection and control, characterized by its advanced interruption technology, integrated monitoring systems, high insulation strength, and user-friendly maintenance features. Its innovative design and engineering make it a trusted choice for utilities and industrial facilities aiming to enhance the reliability and safety of their electrical systems.
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