How should conductors in ferrous metal raceways be arranged to avoid heating from alternating-current induction?

To prevent heating from alternating-current induction in ferrous metal raceways, arranging all conductors together is the correct approach. When conductors are grouped together, the magnetic fields produced by the flow of alternating current in one conductor can effectively cancel out the unwanted electromagnetic effects on the adjacent conductors. This arrangement minimizes the potential for induction heating, as the mutual inductance between closely spaced conductors reduces the overall inductive effect.

Induction heating can occur when conductors are not properly aligned, leading to varying magnetic fields that can induce unwanted currents and heat in adjacent conductors. By grouping conductors, the arrangement promotes a more uniform magnetic field around them, reducing the chances of heating.

In contrast, separating conductors may inadvertently lead to greater exposure to inductive effects, while having only power conductors grouped may not address the heating issues related to signal or control conductors in proximity. Insulating all conductors does provide some level of protection but does not specifically address the issue of inductive heating due to conductor arrangement within ferrous metal raceways. Proper grouping of conductors is essential to maintain safe operational temperatures and minimize inductive interference.