What does it mean that the transformer connection group is YN, yn0, d 1 1?

The connection group of transformer is the representative of the combined connection form of primary winding and secondary winding of transformer.

Clock representation is used to represent the phase relationship between the primary and secondary line voltages. The phasor of the primary side line voltage is used as the minute hand, which is fixed at the position of clock 12, and the phasor of the secondary side line voltage is used as the hour hand. ? Yn, d 1 1, where 1 1 indicates that when the phasor of the primary line voltage is at 12 as the minute hand, the phasor of the secondary line voltage is at1/point.

Extended data:

Precautions:

After the transformer is put into operation, its most economical operation state is that the load capacity reaches 70%-80% of the rated capacity. However, due to the different production conditions of enterprises, the load capacity of transformers will change with seasons, orders and production processes. When it exceeds 80% of its rated capacity, it is necessary to strengthen the monitoring of transformer load current. Usually an ammeter is installed on the low-voltage distribution cabinet, which can be directly observed. If there is no ammeter, you can measure it with a clamp ammeter.

If the transformer runs under overload for a long time, it will seriously shorten the service life of the transformer and increase the loss of the transformer. While detecting the transformer load current, we should also pay attention to balancing the three-phase load current as much as possible.

If the three-phase currents differ greatly, it will lead to three-phase voltage imbalance, neutral point displacement and neutral line electrification, which will lead to the electrification of the electrical equipment shell, which will cause safety hazards to equipment and personnel.

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