PROTECTION & COMMISSIONING: CT Testing , CB Testing.
PROTECTION & COMMISSIONING: CT- IEC Standard? Ans : IEC 60044-1 Difference between X class and PX class. Ans: Both are the same. In old BS It is mentioned X class. In IEC std It is mentioned in PX class. Class PX is the definition in IEC 60044-1 for the quasi-transient current transformers formerly covered by class X of BS 3938, commonly used with unit protection schemes. Explain the CT Testing? CT testing procedure – What are all the test sequences? Before starting C.T testing check the name plate details are matching with the drawing and customer requirements. Confirm the polarity (P 1 , P 2 ) as per drawing. Check if the panel is earthed or not. Verify the test blog number’s / ferrule No’s with drawing. Start the test with following sequence: IR Test Polarity Test Winding Resistance Test Knee point voltage Test Ratio Test Explain CB Testing. Ans: Before starting the test check the name plate details are matching with drawing and customer requirements. Visually inspect C.B ...