What size Flexible Metal Conduit is required for a 14/2 NM cable containing three cables?

To determine the correct size of Flexible Metal Conduit (FMC) required for a 14/2 NM cable containing three cables, we need to consider the NEC (National Electrical Code) guidelines for conduit fill.

The 14/2 NM cable consists of two conductors and a ground, so when we have three of these cables, we actually have a total of six conductors plus their insulation. According to the NEC, there are specific fill ratios that guide how many conductors can be safely placed in a conduit of a given size without exceeding the allowable fill percentage.

In this case, for three 14/2 NM cables (which could be considered as if we are dealing with six conductors), we perform a calculation based on the cross-sectional area of the cables. Each 14 AWG conductor has a given diameter when insulated, along with the ground. By adding up the total cross-sectional area required for the three cables, we find that a 1-inch FMC would accommodate the necessary space per the NEC's fill requirements.

The incorrect sizes would either be too small, not allowing for the safe installation of all cables, or excessively large, which would be inefficient and unnecessary. Therefore, the most suitable size, considering both