Conversion of current transformer ratio and number of turns - News - Global IC Trade Starts Here.

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

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Some current transformers are lost in use. When the user load changes, the current transformer ratio must be changed. First, the transformer should be tested to determine the highest rated current of the transformer, and then the ratio and number of turns should be adjusted as needed. Conversion. It can be calculated as the highest rated current. For example, the ratio of the original current transformer is 50/5, and the number of core turns is 3匝. When using it as a 75/5 transformer, we first calculate the highest rated current. Current: the highest rated current = the primary current in the original use × the original number of cores = 50 × 3 = 150A, the number of cores after the conversion to 75/5 is 150 / 75 = 2, that is, the number of original cores When the 3 匝 50/5 current transformer is converted to a 75/5 current transformer, the core strain is 2 应变. Another example is the current transformer with 50/5 of the original core winding number, which needs to be changed to 75/5 current transformer. We first find the highest rated current of 50×4=200A, and change the wearing after use. The number of core turns should be 200/75≈2.66匝. The number of turns in the actual core can only be an integer, either 2匝 or 3匝. When we wear 2 ,, its primary current has become 200/2=100A, forming a 100/5 transformer, which produces an error, the error is (original ratio - current ratio) / current ratio = (15-20) / 20 = - 0.25 is -25, which means that if we still calculate the electricity according to the ratio of 75/5, we will count less than 25 power. And when we wear 3 ,, we will definitely count the user's power. Because the primary current becomes 200/3=66.66A, a 66.6/5 transformer is formed, and the error is (15-13.33)/13.33=0.125, which is calculated by the ratio of 75/5. Electricity. therefore. Litian Electric reminds everyone: When you don't know the highest rated current of the current transformer, you can't change the ratio at will, otherwise it is likely to cause measurement error.