What is the minimum trade size EMT required for a 45' long run with specified conductors?

The minimum trade size EMT (Electrical Metallic Tubing) required for a 45-foot long run depends on the number and size of the conductors that will be housed within the conduit. Smaller EMT sizes, such as 3/4 inch, are typically sufficient for smaller gauge conductors (such as 14 or 12 AWG) and a limited number of wires.

When the specified conductors are within the capacity of the 3/4 inch EMT, it allows for proper bending radius, sufficient fill capacity according to NEC (National Electrical Code) guidelines, and adequate protection of the conductors over the length of the installation. Additionally, the material properties of EMT provide the necessary support and protection for the conductors in various environments.

It’s also important to consider potential derating factors, such as temperature or conduit fill, that might affect the sizing. However, if the stated conditions of the question indicate that 3/4 inch EMT is acceptable for the application, it confirms the sufficiency of this size for that specific installation. The choice of size should ensure that there is both mechanical protection and compliance with electrical code requirements.