UL1558 standard stipulates the design, construction, performance and safety requirements of low-voltage power switchgear, ensuring that the switchgear can operate safely and reliably in electrical systems. It is mainly applied in North America and projects that follow American standards.

Medium-voltage switchgear available in markets such as Europe and Asia is manufactured in accordance with International Electrotechnical Commission (IEC) standards. However, these switchgear units typically feature rear cable connections, making the installation and maintenance of such equipment difficult.