How long can wires from the motor-generator set to the controller terminals be run exposed?

The correct answer is based on the National Electrical Code (NEC) guidelines, which specify the appropriate lengths for exposed wiring in machine rooms and hoistways. For wiring running from a motor-generator set to the controller terminals, a maximum exposed length of 6 feet is allowed. This limit is set to ensure safety and minimize the risk of physical damage to the wires.

Exposing the wires beyond this length could increase the likelihood of interference, environmental exposure, or mechanical stress, which can compromise the integrity of the electrical connections. By maintaining the 6-foot limit, it allows for easier maintenance and reduces potential hazards associated with longer, exposed wiring runs.

Understanding these regulations is essential for ensuring compliance and promoting safety in the installation and operation of elevator systems.