Regulations for Conducting Visits via Communication Devices in Prisons and Detention Centers Article 11

The duration for each visit to an inmate via communication devices is limited to thirty minutes. Nevertheless, the authority may increase or decrease the duration if it deems necessary to do so.
中文原文 監獄及看守所辦理使用通訊設備接見辦法第11條
收容人使用通訊設備接見,每次以三十分鐘為限。
但機關認有必要時,得調整加減之。

English translation for reference only; the Chinese text prevails. Not legal advice.