3 sentences

1. 那台变压器发生了故障。

   nà tái biàn​yā​qì fā​shēng le gù​zhàng.

   That transformer has broken down.

   Source: Dong Chinese Dictionary

2. 这个变压器由于过载而损坏了。

   zhè​gè biàn​yā​qì yóu​yú guò​zài ér sǔn​huài le.

   The transformer was damaged due to overloading.

   Source: Dong Chinese Dictionary

3. 变压器负责将高压电降压为民用电压。

   biàn​yā​qì fù​zé jiāng gāo​yā​diàn jiàng​yā wéi mín​yòng diàn​yā.

   Transformers are responsible for stepping down high-voltage electricity to residential voltage.

   Source: Dong Chinese Dictionary