Vacuum Circuit Breaker or VCB Advantages 1 Service

Vacuum Circuit Breaker or VCB Advantages : 1. Service life is much longer than other types of circuit breakers. 2. There is no chance of fire hazard as OCB. 3. It is much environment friendly than GCB (SF 6). 4. Replacement of vacuum interrupter (VI) is much convenient. The dielectric strength of vacuum is eight times greater than that of air and four times greater than that of SF 6 gas. This high dielectric strength makes it possible to quench a vacuum arc within very small contact gap. 真空斷路接點部分裝置結構

Oil Circuit Breaker 啟斷情況

Contact Resistance Test Conventional Setup

台電對GCB 、 VCB 、 OCB 、 ABS 、及DS 等斷路器或開關之接 觸電阻要求: 電壓等級 試驗電流 新品 良好(G) 劣化(D) 尚堪用 待檢(I) 不良(B) 斷路器額定電流 / <接觸電阻 161 KV >200 A 800 A <200μ Ω 1000 A <150μ Ω 1200 A <100μ Ω 1500 A <100μ Ω 2000 A <85μ Ω 69 KV >100 A 600 A <400μ Ω 800 A <200μ Ω 1000 A <150μ Ω 1200 A <150μ Ω 1500 A <100μ Ω 22. 8 KV >10 A 600 A <400μ Ω 800 A <300μ Ω 1000 A <200μ Ω 1200 A <150μ Ω 1500 A <100μ Ω 11. 4 KV >10 A 600 A <400μ Ω 800 A <300μ Ω 1000 A <250μ Ω 1200 A <200μ Ω 1500 A <150μ Ω 3. 3 KV >10 A 600 A <500μ Ω 800 A <400μ Ω 1000 A <300μ Ω 1200 A <200μ Ω 1500 A <150μ Ω 備註

DRM Diagnosis: arcing contact length main contact motion arcing contact length dynamic resistance coil current ms

Circuit Breaker Timing Test > Connect to all main contacts > Connect to trip & close coil > Voltage supply required Conventional Setup Time-consuming and error-prone

IEC – CB timing definition ON OFF

IEC – CB timing definition OFF ON

Standards – ANSI > C 37. 04 -1999 > Standard ratings defined > C 37. 06 -2000 > Schedule of preferred ratings > C 37. 09 -1999 > Type tests > Routine tests > C 37. 081, C 37. 082, IEEE 693 © OMICR Page 36

Standards – IEC > IEC 62271 -100, 2001 > Type, routine & field tests > Timing definitions > Guide for selection and specification > IEC 60694, 2001 > Normal service conditions > Schedule of preferred ratings > Altitude correction > IEC 60427, IEC 60815, 60529, IEC 61166, IEC 61233 © OMICR IEC Page 37