What are the considerations for using rigid and flexible metal conduits together?

Many applications and installations will require transition solutions between rigid and flexible cable protection systems. These transition solutions must provide continuity of performance, ratings, approvals, and regulatory requirements. When choosing a transition solution, the following key factors should be considered:

System materials and corrosion protection: Rigid and flexible systems are specified by installation requirements, including environment, application and installation environment. Steel, aluminum, stainless steel and coating solutions can be used for the rigid and flexible components required for a complete installation solution.

System entry level: Both rigid and flexible systems have entry levels that comply with UL, CSA, NEMA and IEC IP levels. These entry levels ensure that the entire system can meet the requirements for dust, water, rain and temporary immersion. A clear understanding of the inlet requirements of the installation is required to select products with appropriately listed and certified inlet ratings. Helps ensure the integrity of the entrance of the complete installation between the cable protection system, enclosure and control device.

System temperature ratings: Rigid conduit systems inherently have very high temperature ratings for uncoated and coated products. The flexible conduit system now offers dedicated high temperature (HT) solutions, ranging from -60 to +150°C (-72 to +302°F).

Conversion of trade sizes: According to installation requirements, conduits and fittings may need to be converted between different trade sizes. For example, the system may need to transition from a 1” rigid body to a 3/4” flexible conduit and fittings. These transitional requirements can be easily solved by using "amplifiers" or "shrinkers", which are available in a variety of size combinations and materials.

Thread type conversion: In some applications, it may be necessary to convert between different thread types (including NPT, ISO metric, PG, and other thread types). When encountering these applications, you can apply the "thread converter" to perform these conversions.

Approvals and certifications: Choosing products with appropriate lists, certifications and approvals will help provide a safe and reliable installation.