What is the maximum size rigid metal conduit that is allowed for use?

Rigid metal conduit (RMC) is widely used for protecting electrical wiring systems in various applications due to its durability and robust nature. The National Electrical Code (NEC) outlines specific guidelines regarding the installation and usage of conduits, including the maximum allowable size for rigid metal conduit.

In the context of the question, trade size 6 is indeed the maximum size permitted for rigid metal conduit as per the NEC. This allows for substantial wiring systems while ensuring that the conduit maintains structural integrity and is manageable during installation. Larger sizes, such as trade size 7 and beyond, may not be recognized under the regulations for RMC and are typically reserved for different types of conduit systems which may have varying properties and permissible applications.

Knowing the maximum allowable size is crucial for professionals working with electrical installations to ensure compliance with safety standards and regulatory requirements, ensuring the successful deployment of electrical systems.