How To Choose A Suitable Transformer And Determine Its Reasonable Capacity?

How to choose a suitable transformer and determine its reasonable capacity?
When choosing a transformer, you need to consider multiple factors comprehensively. First, you need to understand the power supply voltage of the place where electricity is used, the actual power load of the user, and the conditions of the location. Then, refer to the technical data indicated on the nameplate of the transformer to select one by one. In the selection process, the capacity, voltage, current and environmental conditions of the transformer should be considered comprehensively. It is particularly important to note that the selection of capacity should be based on the capacity, nature and usage time of the user's electrical equipment to determine the required load, so as to select the appropriate transformer capacity.
Under normal operating conditions of the transformer, the power load it bears should be controlled at about 75-90% of the rated capacity. If the actual measured load borne by the transformer is less than 50%, you should consider replacing a small-capacity transformer; when the load exceeds the rated capacity, you should immediately replace it with a large-capacity transformer.

At the same time, when selecting a transformer, the voltage value of the primary coil needs to be determined according to the line power supply, and the voltage value of the secondary coil needs to be selected according to the electrical equipment. It is recommended to use a low-voltage three-phase four-wire power supply method to meet the power and lighting power needs at the same time. In addition, when selecting the current, it should be ensured that the current can meet the requirements of the motor when the motor starts, because the current at the start of the motor is usually 4 to 7 times larger than the current during normal operation.

 

It is worth noting that the transformer should not be overloaded. Overload operation means that the transformer exceeds the current value specified on the nameplate during operation. It may include normal overload and accident overload. Normal overload is usually caused by increased power consumption by users. Long-term normal overload operation will cause the transformer temperature to rise, accelerate insulation aging, and thus shorten its service life. Therefore, the transformer should avoid overload operation under normal conditions. In special circumstances, if short-term overload operation is required, the overload degree should not exceed 30% (winter) and 15% (summer) of the rated load. For accident overload, specific allowable overload time and requirements must be followed.