Among the electric power test workers, there are many electric power test workers who are doing transformer AC withstand voltage test, switch cabinet withstand voltage test, etc. Many test transformers are also used, some commonly used are oil-immersed test transformers and gas-filled test transformers. However, when the unit purchases these test equipment, they don’t know how to choose the appropriate test transformer according to the tested product. The wrong purchase often leads to replacement and delays in work. Today, I will introduce you to the capacity selection skills of the test transformer. To test the transformer, what is the transformer capacity and how to choose?

1. What is a test transformer?

The test transformer, as the name suggests, is a type of transformer. Strictly speaking, it is a special type of transformer, because the conventional transformer used for transformation and distribution is generally called a power transformer. Because its purpose is to make AC withstand voltage, which is called the test, it is named test transformer. Also called AC test test transformer, power frequency withstand voltage test device and so on.

2. Test transformer capacity

The capacity of the test transformer is the same as that of a conventional power transformer. The capacity is still calculated in KVA. For example, power transformers have national standard specifications, although test transformers do not have national standard specifications. However, due to many years of industry use characteristics and a lot of practical experience, industry standards have also been produced. The general test transformer capacity is 3KVA/5KVA/10KVA/30KVA and so on. The test transformers of these commonly used specifications are the most cost-effective, because other specifications are generally special specifications, that is to say, they are customized series. The capacity of the test transformer is also proportional to the weight, and the capacity and weight cannot be achieved at the same time. The capacity of the test transformer can also be tested with a transformer capacity tester.

Three, test transformer capacity selection

According to a large amount of field experience, in terms of the withstand voltage of power transformers, we generally choose to test the transformer capacity according to 5‰ (five thousandths). What does it mean, for example. We now have a 1600KVA 10KV distribution transformer. When selecting the model, we first determine the capacity. Five thousandths of 1600 is 8KVA. At the same time, the AC withstand voltage test of 10KVA oil-immersed distribution transformer is 28KV. We need an 8KVA/28KV test transformer, which is not a common specification. In addition to customization, we also have a more cost-effective option, which is to directly choose a 10kVA/50kV test transformer.