How is the 120 V supply outlet protected in low-voltage transformers?

The 120 V supply outlet in low-voltage transformers is typically protected by a ground fault circuit interrupter (GFCI). A GFCI is designed to prevent electrical shock by monitoring the electrical current flowing through a circuit. If it detects any imbalance in the current, which can occur if there is a ground fault or if electricity is leaking through an unintended path (such as a person), it quickly shuts off the power supply to prevent injury.

In the context of low-voltage transformers, which often operate around or under 120 volts, it is essential to prioritize safety due to the potential for contact with water or damp conditions, common in landscaping environments. The GFCI provides this critical protection, ensuring that any fault condition will result in immediate disconnection of the supply, minimizing the risk to individuals working near or with the transformer.

Other protective devices, such as fuses or surge protectors, serve different purposes. Fuses provide overcurrent protection by breaking the circuit when the current exceeds a certain threshold, whereas surge protectors protect against voltage spikes. However, these do not specifically mitigate the risks associated with ground faults that could lead to electric shock, which is why a GFCI is the preferred method of protection for this application.