The main technical data are generally marked on the nameplate of the transformer.

Mainly include: rated capacity, rated voltage and its tap, rated frequency, winding coupling group and rated performance data (impedance voltage, no-load current, no-load loss and total weight of load loss.

A, rated capacity (kVA): rated voltage. Rated current under continuous operation, the capacity can be delivered.

B, rated voltage (kV): the working voltage that the transformer can withstand when operating for a long time. In order to adapt to the needs of changes in grid voltage, transformer high-voltage side are tapped, by adjusting the number of turns of high-voltage winding to adjust the output voltage of the low-voltage side.

C, rated current (A): the transformer in the rated capacity, allowing long-term current through.

D. No-load loss (kW): When the rated voltage at the rated frequency is applied to the terminals of one winding, the active power drawn by the rest of the winding is open circuit. With the core silicon steel sheet performance and manufacturing process, and the applied voltage related.

E, no-load current (%): When the transformer is no-load on the second side at rated voltage, the current passed in the primary winding. Generally expressed as a percentage of the rated current.

F, load loss (kW): the transformer’s secondary winding short-circuit, in the primary winding rated tap position into the rated current, when the transformer power consumption.

G, impedance voltage (%): the transformer’s secondary winding short-circuit, in the primary winding slowly raise the voltage, when the secondary winding short-circuit current is equal to the rated value, when the voltage applied to the primary side. Generally expressed as a percentage of the rated voltage.

H, the number of phases and frequency: the beginning of the three-phase to S, single-phase beginning to D said. China’s national standard frequency f for 50Hz. 60Hz foreign countries (such as the United States).

I, temperature rise and cooling: transformer winding or upper oil temperature and transformer temperature difference between the surrounding environment, known as the winding or upper oil temperature rise. Oil-immersed transformer winding temperature rise limit of 65K, oil surface temperature rise of 55K. cooling methods are also various: oil-immersed self-cooling, forced air cooling, water cooling, tube, sheet type, etc..

J. Insulation level: There are insulation level standards. The insulation level is expressed as follows: the insulation level of transformer with high voltage rated voltage of 35kV and low voltage rated voltage of 10kV is LI200AC85/LI75AC35, where LI200 means that the transformer has high voltage lightning surge withstand voltage of 200kV and frequency withstand voltage of 85kV, low voltage lightning surge withstand voltage of 75kV and frequency withstand voltage of 35kV. withstand voltage of 35kV.

Transformer main parameters