Extra Low Voltage Distribution System Design & Installations
Extra-Low Voltage (ELV) means the voltage of electricity supply is in a range that is low enough that it does not carry any high risk of any high voltage electrical shock(s).
The range of voltage that can be classified as Extra-Low Voltage is alternating current not exceeding 50 V AC and direct current not exceeding 120 V DC (ripple free)
Examples of ELV systems are CCTV, Card Access System, Public Address System.