Micro transformers are divided into micro current transformers (including micro current converters) and micro voltage transformers. They are equipment in the power industry, generally used in various power instruments for measurement and protection purposes. Compared to ordinary transformers, micro transformers have smaller size (which can be as small as a fingernail) and higher accuracy (ordinary transformers have four accuracy levels: 0.5, 0.5S, 0.2, 0.2S, while micro transformers can reach level 0.1).

The miniature voltage transformer is a current-type voltage transformer, with the primary circuit incorporating a resistor in series,

WYH1, 2 series voltage transformers

WYH1, 2 series voltage transformers

 Secondary parallel resistance. The voltage is converted into current, and after current transformation by a transformer, the primary output current signal is converted into the required voltage through a sampling resistor. Most micro voltage transformers are plugged into circuit boards for use.

The primary side of a micro current transformer (including micro current converter) has no resistance, while the ordinary micro current

WYH1, 2 series voltage transformers

WYH1, 2 series voltage transformers

 The transformer is a transformer with parallel resistance on the secondary side, and the output is current. The micro current transformer's micro current converter has parallel resistance on the secondary side, and the output is voltage. Micro current transformers are divided into two types of usage: multi-turn winding type (inserted on the circuit board) and through-core type.