What is the maximum voltage for extra low voltage systems?

The maximum voltage for extra low voltage systems is defined as 50V AC or 120V DC. Extra low voltage (ELV) systems are designed to minimize the risk of electric shock and ensure safety in environments where electrical systems are accessible to people.

The 50V AC threshold is significant because it is below the level where a serious electric shock could be expected under normal conditions. This standard helps in creating safer installations, especially in public spaces and residential areas.

While 25V AC is commonly used for low voltage signaling and control systems, it is not the upper limit for ELV systems. Similarly, 100V AC and 120V DC exceed the thresholds defined for extra low voltage, thereby not fitting into the ELV category. Thus, the classification of ELV distinctly identifies 50V AC as the defining maximum voltage for systems meant to maintain a high standard of safety.