Where must all conductors of the same circuit be contained?

All conductors of the same circuit must be contained within the same trench or raceway to ensure that they are properly grouped. This requirement helps to minimize issues related to electromagnetic interference and allows for easier identification of the circuits during maintenance and inspections.

By keeping all conductors of the same circuit together, it also ensures that they have a similar thermal environment, as different locations or enclosure types can lead to uneven heating or exposure to environmental conditions that could negatively affect the performance and safety of the circuit.

Moreover, grouping conductors in a trench or raceway provides physical protection and helps to comply with NEC requirements regarding accessibility, protection from physical damage, and maintaining circuit integrity. This is particularly important during installation and maintenance, as it simplifies troubleshooting and reduces the risk of errors that could arise from having conductors in disparate locations or configurations.