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Transformer current calculation method

Calculating the rated current and voltage is a necessary knowledge of a transformer-related technician, and the transformer current is divided by the port algorithm and the formula method. In this section, we will show the port algorithm.
 
Transformer operating load requirements
For example: A 800KVA10 / 0.4KV transformer, according to a secondary current calculation, the various load current is how much?
Solution: a current I = S * 0.06 = 800 * 0.06 = 48A
Secondary current I = S * 1.5 = 800 * 1.5 = 1200A
Low load: a current I = 48 * 15% = 7.2A
Secondary current I = 1200 * 15% = 180A
Reasonable load: a current I = 48 * 50% = 24A
Secondary current I = 1200 * 50% = 600A
Full load: a current I = 48 * 75% = 12A
Secondary current I = 1200 * 75% = 900A
 
Three-phase transformer current calculation formula I = S / (root number 3 * U), where U is the transformer line voltage, KV
Transformer Current Experience Port Algorithm: Primary Current IS * 0.06 Secondary Current IS * 1.5
For example: A 500KVA transformer to calculate the primary current and secondary current, with the current formula I = S / (root number 3 * U)
I = 500 / root number 3 * 10 = 500 / 17.3228.8A
I = 500 / root number 3 * 0.4 = 500 / 0.69 = 724.6A
Transformer current empirical calculation formula: I = 500 * 0.06 30A I = 500 * 1.5 = 750A
 
When working with an industry, this formula is relatively important for calculating how much current to recommend to customers and how much current is recommended. Therefore,  we should accumulate these experiences for ourselves in our daily life.
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