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MAINTENANCE

CRITERIA:

1.If a current flow above 5 milliamperes is observed or if breakdown occurs, one or more of the interrupters has insufficient vacuum and must be replaced.

Exception: If the current exceeds 5 milliamperes the first time the voltage is brought up, reduce the voltage to zero and increase it again. It may be necessary to repeat this procedure a few times.

2.If the breaker fails to meet criteria 1, then repeat the test on each pole separately to identify the damaged interrupter or interrupters.

3.If the voltage can be held for 1 minute and the current flow does not exceed 5 milliamperes, the interrupter has a sufficient vacuum level.

After the test is complete, discharge any residual static charge from the primary terminals of the circuit breaker.

If a vacuum checker or AC hi-pot tester is not available, a DC hi potential test may be conducted. If a DC test is conducted, the test voltage must be increased to 31kV DC. The test duration for DC tests and the criteria for acceptance remain the same as for AC tests.

Fig. 35 Application of Test Voltage for Vacuum Check

22kV AC

1 minute

 

(31kV DC)

 

Voltage

 

Zero

 

15 sec

15 sec

 

Time

WARNING

Do not use DC hi-pot testers which employ unfiltered half-wave rectifiers. The peak voltages produced by these testers may exceed the recommended value of 31kV. This can result in the production of harmful X- rays and may invalidate the test results.

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Toshiba HV6AS instruction manual Criteria, Voltage

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.