MAINTENANCE

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VACUUM CHECK

A sufficient level of vacuum is necessary for proper performance of the vacuum interrupters. Although vacuum leaks are rare, the vacuum integrity should be checked periodically. The

WARNING

Hazardous voltages are present during dielectric testing which can result in severe injury or death. Only qualified personnel should conduct this testing.

relationship between dielectric breakdown voltage of the contact gap and internal vacuum interrupter pressure has been found to be generally predictable. Therefore, vacuum interrupter integrity is checked by performing a high potential test across the open gap of the interrupter.

TEST EQUIPMENT:

Toshiba offers a compact vacuum checker (Type CI35-1D) which enables a quick and easy check on vacuum interrupter internal pressure. Alternatively, any commercially available AC high potential tester may be used which is capable of delivering at least 25 milliamperes at 22 kV for a period of one minute.

PRECAUTIONS:

Applying abnormally high voltage across a pair of contacts in vacuum may produce X-rays. The radiation may increase with the increase in voltage and/or decrease in contact spacing. X- radiation produced during this test with recommended voltage and normal contact spacing is extremely low and well below the maximum permitted by standards. As an additional safety measure, however, it is recommended that all personnel keep at least 1 meter (3.3 ft) away from the vacuum circuit breaker while this test is performed.

TEST PROCEDURE:

1.The circuit breaker should be disconnected from the main circuit and be in the OFF position.

2.Connect all the line side primary terminals together and to the output of the vacuum checker or AC hi-pot machine. Connect all the load side primary terminals together and to the ground terminal of the vacuum checker or AC hi-pot machine.

3.Increase the voltage from zero to 22kV AC at a rate of approximately 2kV per second. Hold the voltage at this value for 1 minute and observe the current drawn by the interrupter.

4.Decrease the voltage back to zero.

Fig. 34 Toshiba Portable Vacuum Checker

WARNING

Radiation exposure hazard. X-rays may cause illness or injury. Stay at least 1 meter (3.3 ft) away from the circuit breaker during the vacuum check test .

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Toshiba HV6AS instruction manual Vacuum Check, Test Equipment
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HV6AS specifications

The Toshiba HV6AS is a sophisticated high-voltage IGBT (Insulated Gate Bipolar Transistor) module, primarily designed for demanding applications in industrial and energy sectors. This module stands out due to its superior performance characteristics, which allow it to handle high voltages while delivering optimal efficiency and reliability.

One of the key features of the HV6AS is its high voltage rating, typically around 650V, making it suitable for various applications including motor drives, renewable energy systems, and UPS (Uninterruptible Power Supply) systems. This voltage capacity enables the module to effectively control large power loads, ensuring excellent performance in high-demand environments.

The HV6AS adopts cutting-edge technologies that improve its operational efficiency. The design incorporates advanced thermal management features, which help in enhancing its reliability and lifespan. Integrated with a robust heat sink, the module efficiently dissipates heat generated during operation. This is crucial as increased temperatures can lead to reduced performance and potential failure.

Additionally, the HV6AS utilizes a double-sided cooling structure, which allows for superior thermal conductivity and enables the module to perform optimally in high-temperature conditions. This aspect is particularly important for applications in renewable energy, such as solar inverters, where efficiency and durability are key.

Another notable characteristic of the HV6AS is its fast switching capability. The IGBT technology allows for rapid switching between on/off states. This feature is essential in applications such as pulse-width modulation (PWM), contributing to improved power conversion efficiency. The high switching frequency capability means that systems can operate more efficiently, resulting in lower energy losses.

Toshiba’s HV6AS also focuses on enhancing productivity through simplified circuit design. Its compact form factor means that it can be easily integrated into existing systems, saving space and simplifying installation processes. The module’s compatibility with existing drive technologies allows for seamless upgrades to newer systems without significant changes to the overall architecture.

In summary, the Toshiba HV6AS is a highly versatile IGBT module characterized by its high voltage capability, advanced thermal management, fast switching speed, and compact design. These factors make it an excellent choice for a wide array of high-performance applications in various industries, driving innovation towards more efficient and sustainable power solutions. Whether in industrial automation or renewable energy, the HV6AS sets a benchmark for reliability and effectiveness in power electronics.
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