When are double locknuts permitted for bonding with rigid metal raceways?

Double locknuts are permitted for bonding with rigid metal raceways specifically when the raceway contains any wire of more than 250V to ground. This practice is primarily focused on ensuring safety and preventing electrical hazards. When dealing with higher voltage systems, establishing a secure and proper bond is critical to avoid electrical faults that could lead to dangerous situations.

The double locknuts provide a reliable method of ensuring that the raceway is grounded effectively, which is essential for maintaining safe operations in environments dealing with higher voltages. Using double locknuts enhances the mechanical stability and electrical conductivity necessary for bonding in these conditions, thus complying with safety standards and regulations.

In scenarios where the raceway does not contain wires exceeding 250V to ground, other bonding methods may be adequate, making double locknuts less critical or necessary. Understanding the context of voltage levels in electrical systems is crucial for choosing appropriate bonding methods.