How many conduits must be threaded wrenchtight into an enclosure for it to be considered supported if it is not over 100 cu in.?

For an enclosure that is not over 100 cubic inches, it must have two conduits threaded wrenchtight for it to be considered properly supported. This requirement ensures stability and strength in the electrical system by preventing movement or disengagement of the conduits, which could compromise the integrity of the connections and the safety of the installation.

The NEC recognizes that a single conduit may not provide adequate support for heavier loads or stresses that can occur in an electrical system. By requiring two conduits, the code helps to ensure that there is redundancy and that if one conduit experiences a failure or becomes loose, the other can still maintain the structural integrity and electrical connections. This is especially important in environments with potential vibration, movement, or other stresses that could affect the connections.

The options that propose fewer than two conduits do not meet the NEC requirements for support in this context, as they could lead to an unsecured installation, which poses risks for both safety and functionality.