Which flexible cord type is required for connecting equipment with specific grounding and ungrounded conductor needs?

The type of flexible cord that is specifically designed for connecting equipment with certain grounding and ungrounded conductor requirements is the SJO type. SJO cords are constructed with thermoplastic insulation and are suitable for use in applications where exposure to moisture, oil, and mechanical stress is a concern. They include both an ungrounded conductor and a grounding conductor, which makes them versatile for various electrical setups, including those that require adherence to specific grounding practices.

SJO cords are often used in a variety of portable applications, including power tools and lighting, where flexibility and durability are essential. The combination of these features makes SJO cords particularly appropriate for ensuring safe and reliable connections in environments that demand attention to grounding and insulation standards.

Other types such as SEO, SJOW, and SOOW each have applications that may not align as closely with the specific grounding and ungrounded conductor needs mentioned in the question. Thus, SJO stands out as the suitable choice for this specific requirement.