What is the maximum length of a non-metallic conduit run without an expansion fitting?

The maximum length of a non-metallic conduit run without an expansion fitting is indeed 100 feet. This guideline is based on the thermal expansion characteristics of non-metallic materials, such as PVC, which can expand and contract with temperature changes. If a run of non-metallic conduit exceeds this length without the inclusion of an expansion fitting, the risk of damage or failure increases due to the stresses created by expansion and contraction.

In practical terms, when planning electrical installations involving non-metallic conduit, it's essential to adhere to this limit to ensure system integrity and longevity. Using expansion fittings accordingly helps accommodate the thermal movement, thus preventing potential issues such as cracking or distortion of the conduit, which can lead to compromised electrical installations.