... High Reliability -Master (MST) cards and power supply cards adopt hot redundant backup-Advanced circuit design, modular structure.-Adopting low power ... consumption, high reliable component-All functional cards support hot swapSmart Shelf -3U high, 19 standard shelf-Compact, beautiful, ... supply card The ring supply card generator ring for FXS, HOT, CRR and MAG cardsPWR board-48V DC or 220V AC ...