3000VA Control Transformer, 440/460/480V to 120/24V

3kVA single phase control transformer, converting 440/460/480V input to 120/24V output, fully electric isolation between the primary side and secondary sides, is suitable for circuit of AC 50/60Hz and rated voltage 500V and below.

Specifications

Schematic diagram illustration

 Control transformer dimension

Tips: Transformer No-load Operation vs. Load Operation

Transformer no-load operation

The no-load operation of the transformer refers to the working state that the primary winding of the transformer is connected to the power supply and the secondary winding is open circuited. At this time, the current in the primary winding is called the no-load current of the transformer. No load current produces no-load magnetic field. The electromotive force is induced in the primary and secondary windings under the action of the main magnetic field (i.e. the magnetic field of the primary and secondary windings are linked at the same time).

During no-load operation of the transformer, although there is no power output at the secondary side, the primary side still draws part of the active power from the grid to compensate for the hysteresis loss and eddy current loss caused in the core due to flux saturation, which is called iron loss for short. The magnitude of the hysteresis loss depends on the frequency of the power supply and the area of the hysteresis loop of the core material; the eddy current loss is proportional to the maximum flux density and the square of the frequency. In addition, there is copper consumption caused by no-load current. For different capacity transformers, the magnitude of no-load current and no-load loss is different. So when using a transformer, we must choose suitable capacity.

Transformer load operation

Load operation of the transformer refers to the working condition when the primary winding is connected to the power supply voltage and the secondary winding is connected to the load. At this time, the secondary side of the transformer also has current flow, the access circuit of the original transformer increases correspondingly compared with no-load, and the voltage of the secondary side will be affected by the load and change.