C-Tec Switch Mode Power Supply Unit Ideal for powering beam detectors, auto-dial communicators, aspirating smoke detectors, auto-open vent systems, auxiliary sounder systems or any other device performing a mandatory function of a fire alarm system. Includes a single-pole volt-free changeover relay that switches for any fault condition. A boxed Mains to regulated DC power supply providing 1.5A at 24VDC. Fully compliant with EN54-4. It is available with supply present-green, general fault -amber, auxiliary fault amber and hazardous voltages present red Indicators. Deep discharge battery protection and EN54 compliant reporting of battery impedance faults.