What is the ampacity of two 8 AWG THWN-2 copper conductors installed in rigid metal conduit at an ambient temperature of 95 degrees F?

To determine the ampacity of two 8 AWG THWN-2 copper conductors installed in rigid metal conduit at an ambient temperature of 95 degrees Fahrenheit, it is essential to refer to the guidelines set by the National Electrical Code (NEC) and consider the specific conditions affecting ampacity.

The ampacity for conductors varies based on several factors, including the size of the conductor, type of insulation, and the installation environment. For 8 AWG THWN-2 copper conductors, the base ampacity is typically established under standard conditions, usually at a lower ambient temperature.

Given that the ambient temperature is 95 degrees Fahrenheit, which exceeds the standard rating conditions, it is necessary to apply temperature correction factors. The ampacity for 8 AWG THWN-2 copper conductors, usually rated at 70 A under 30 degrees Celsius (86 degrees Fahrenheit), would need to be adjusted for the higher temperature.

In general, the established correction factors indicate that as temperature rises, the allowable current must be reduced to prevent overheating. For temperatures around 95 degrees Fahrenheit, a specific reduction in ampacity applies. Upon applying the correction factors correctly, you arrive at the value of 53 A for the paired conductors.