... us based on the customer demand to improve the reliability of the transmission electric circuit. This equipment divides 1-line E1 ... 19” 3U structure, with maximum installation of 13 pieces of business inserting boards, 2 pieces of mutual-backup 48V power supply inserting board ... , the power supply can be arrange as the working mode of AC220 V/DC48V), double DC, single AC, single DC, the network ...