The Dual 4-wire Analog AC Data optical interface cards isolate two AC 4-wire lines using fiber links. Two different cards are used to achieve this functionality. The CO side uses a CO interface card at the CFJ (Copper Fiber Junction). The CO interface card at the CFJ is powered from a local power supply of -48 Vdc or from an express pair feeding - 48 Vdc or -72 Vdc. The CFJ optical module interfaces to the CO and transmits in full duplex. It allows simplex sealing current of less than 4 mA. The Station-side uses a Station interface card at the OEI (Optical Electrical Interface). The Station-side interface card (OEI) is powered from the shelf’s backplane supply of -48 Vdc. The card interfaces with the Station side and transmits in full duplex.
The Station-side (OEI) module provides LED statuses on the front plate and generates alarms in the event of a problem with the circuit.
The CO-side (CFJ) module provides an LED to confirm the presence of -48Vdc to power the card.