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Fire-hited electrical equipment has possibility of deterioration. So its replacement is essential in terms of safety. However, the economic burden is increased. Therefore, the replacement or re-use of it is to be determined by tests. But the research of Integrity Assessment on Fire-hited electrical equipments is very rare. In this paper, we tested to determine the replacement or re-use of Fire-hited vacuum circuit breaker. And provided the data for the integrity assessment through the analysis of its deterioration.

If leakage current is neglected, it can become a cause for disasters such as electric shock and fire, therefore a continuous monitoring is necessary. However in most cases, because management of substations is performed by unmanned systems, or walk-around inspections, continuous monitor is difficult. So when an accident occurs and the cause is not immediately resolved causing the emergency generator`s OCGR getting activated by the leakage current that in turn cut off the ACB, the emergency generator may stop working. To prevent such a problem, a real-time integrated monitoring system for monitoring the leakage current returning to the grounding wire of neutral point of the low voltage side of transformer is proposed. Therefore in this paper, the effects of flow of leakage current, which is caused by insulation degradation phenomena or insulation destroy phenomena, were identified by simulation. And through cases studies; the excellence of integrated monitoring system was verified.

SrBi 2.4 Ta 2 O 9 (SBT) thin films of 70–400 nm thickness were prepared on platinized Si substrates by liquid-source misted chemical deposition (LSMCD), and the thickness dependence of the ferroelectric characteristics was investigated. The grain size of the LSMCD-derived SBT films was approximately 150 nm and hardly varied with the film thickness. The 70-nm thick SBT film exhibited remanent polarization (2 P r ) of 13.5 μC/cm 2 and a coercive field value (E c ) of 63 kV/cm at ±3 V. Within the thickness range of 70–400 nm, the LSMCD-derived SBT films exhibited size effects, i.e. a decrease in remanent polarization and relative permittivity and an increase in the coercive field with a reduction in the film thickness. The LSMCD-derived SBT films with a thickness of 70–400 nm exhibited fatigue-free behavior for up to 10 12 switching cycles.