Which of the following is NOT a type of protective equipment used on a distribution line?

The correct answer is the transformer, as it does not function as a protective device in the same context as the other options listed. A transformer is primarily used to change the voltage level in a distribution system, either stepping it up or stepping it down, which is crucial for efficient energy transmission and distribution.

In contrast, fused cutout switches, sectionalizers, and reclosers are all designed specifically for protection and fault isolation within the electrical system. Fused cutout switches help to protect lines by disconnecting them when a fault is detected, thereby preventing damage to equipment and ensuring safety. Sectionalizers work in conjunction with reclosers; they detect and isolate faulted sections of the line after a temporary outage, allowing the rest of the system to remain operational. Reclosers provide the capability to automatically restore service after a temporary fault has cleared, enhancing operational reliability.

Thus, the key distinction lies in the function: while the transformer is an essential component for voltage regulation, it does not serve a protective role, making it the correct choice in this context.