Transformer

Different Types of Primary and Secondary Connections of Transformer Q. State the suitability of following type of 3-phase transformer: (i) Y-Y (ii) Y-∆  (iii) ∆– ∆ (iv) ∆ – Y Q. Draw the connection diagram, symbol and phasor diagram of phasor group-1 (New phase displacement) of transformer connection (i) Y-Y (ii) ∆–∆ (iii) ∆-Z Q. Explain Zig-Zag connection of transformer. Types of Primary … Read more

Comparison of Core Type and Shell Type Transformer Q. Difference between core type and shell type transformer. Sr. No. Core Type Shell Type 1. Figure (A) In this type, the windings enclose the whole core. Figure (B) In this type, the core encloses the windings. 2. Average length of the core is more. Average length … Read more

Constructional Details of Transformer (Single Phase) The transformer has two windings primary and secondary. These windings are made of enamelled copper. These windings are suitably put on the limbs of the transformer core. A suitable insulation is used for the former on which the windings are put. The transformer core is made of silicon steel … Read more

Oil Level Indicators in Transformer After 1 month of service, and every 3 to 5 years, check the tank oil level indicators. These are float operated, with the float mechanism magnetically coupled through the tank wall to the dial indicator. As level increases, the float rotates a magnet inside the tank. Outside the tank, another … Read more

TESTING AND QUALITY ASSURANCE (QA) DURING MANUFACTURE Unlike many items of electrical power plant (for example, switchgear and motors) most transformers are still virtually handmade, little or no mass production is employed in manufacture and each is produced very much as a one-off. This means that the user cannot rely on extensive type testing of … Read more

For protection of transformer against to overcurrent which protection is provided To protect transformer we mostly proved protection against overcurrent, overvoltage, undervoltage and under frequency. In that most important is Overcurrent protection, we use Circuit Breaker for protection of transformer. Types of Circuit breaker use for protection of Transformer 1. Air Circuit Breaker (ACB) 2. … Read more

Transformer Rated power (KVA) Impedance % Up to 630 4 % 631 to 1 250 5 % 1 251 to 2 5oo 6 % 2 501 to 6 300 7 % 6 301 to 25 000 8 % 25 001 to 40 000 9 % 40 001 to 63 000 10 % 63 001 to … Read more