Dry-type Transformer Product Selection

Dry-type Transformer Product Selection

Distribution transformers are one of the important equipment in the power supply and distribution system of industrial and mining enterprises and civil buildings. They reduce the 10⑹kV or 35kV network voltage to the 230/400V bus voltage used by users. This type of product is suitable for AC 50 (60) Hz, three-phase maximum rated capacity 2500kVA (single-phase maximum rated capacity 833kVA, single-phase transformers are generally not recommended)
1) When there are a large number of primary or secondary loads, it is advisable to install two or more transformers. When any of the transformers is disconnected, the capacity of the remaining transformers can meet the power consumption of the primary and secondary loads. The primary and secondary loads should be concentrated as much as possible and should not be too dispersed.
2) When the seasonal load capacity is large, it is advisable to install a special transformer. For example, the air conditioning refrigeration load in large civil S4270D27-29 27 2005.7.29,3:24 AM buildings, heating electric heat load, etc.
3) When the concentrated load is large, it is advisable to install a special transformer. Such as large heating equipment, large X-ray machines, arc furnaces, etc.
4) When the lighting load is large or the power and lighting use a common transformer that seriously affects the lighting quality and bulb life, a dedicated lighting transformer can be installed. In general, power and lighting share a common transformer.
Select transformers according to the use environment:
1) Under normal medium conditions, oil-immersed transformers or dry-type transformers can be selected, such as industrial and mining enterprises, agricultural independent or attached substations, community independent substations, etc. The available transformers are S8, S9, S10, SC (B) 9, SC (B) 10, etc.
2) In multi-story or high-rise main buildings, non-combustible or flame-retardant transformers should be selected, such as SC (B) 9, SC (B) 10, SCZ (B) 9, SCZ (B) 10, etc.
3) In places where dust or corrosive gases seriously affect the safe operation of transformers, enclosed or sealed transformers should be selected, such as BS 9, S9-, S10-, SH12-M, etc.
4) High and low distribution devices without flammable oil and non-oil-immersed distribution transformers can be installed in the same room. In this case, the transformer should be equipped with an IP2X protective casing for safety.
Select transformers according to power load:
1) The capacity of the distribution transformer should be based on the facility capacity of various power-consuming equipment to calculate the calculated load (generally excluding fire load). The compensated apparent capacity is the basis for selecting the capacity and number of transformers. The load rate of general transformers is about 85%. This method is relatively simple and can be used to estimate capacity.
2) GB/T17468-1998 "Guidelines for the Selection of Power Transformers" recommends that the capacity of distribution transformers should be determined according to GB/T17211-1998 "Guidelines for the Load of Dry-Type Power Transformers" and the calculated load. The above two guidelines provide computer programs and normal cycle load diagrams to determine the capacity of distribution transformers.
Installation points
The distribution transformer is an important component of the substation. The dry-type transformer without a casing is directly installed on the ground with protective fences around it; the dry-type transformer with a casing is directly installed on the ground. For its installation, please refer to the National Building Standard Design Atlas. 03D201-4 10/0.4kV Transformer Room Layout and Installation of Common Equipment Components in Substations.