Which element shall not support luminaires weighing over 6 lbs?

Lampholders are typically designed to support only the weight of the lamp itself, which usually is significantly lower than 6 lbs. They are not intended for any additional load, such as attaching a luminaire or light fixture that exceeds this weight. This limitation is crucial for safety reasons, as using a lampholder to support a heavier fixture could lead to mechanical failure, posing a risk of the fixture falling.

In contrast, outlet boxes are specifically designed to support fixtures and devices, and they are subject to building codes that require them to hold the specified weight of luminaires in a safe manner. Terminals are components used in electrical connections and are not weight-bearing elements; their role is strictly electrical. Hence, the safe operation and structural integrity of lighting systems rely on using components appropriately engineered for their specific applications.