GE Multilin L60 Line Phase Comparison Relay 3-233 HARDWARE 3.2 WIRING33.2.10 L60 CHANNEL COMMUNICATIONSAs described earlier in this chapter, L60 communications channels reside on the special CT/VT module (type 8P). Thismodule allows for all possible 87PC scheme combinations (such as dual phase comparison or single-phase comparison,two-terminal or three-terminal applications) in one module. The customer can upgrade or change the scheme at any time.The L60 channel interface requires an external battery to drive inputs and outputs. The module can be used with any bat-tery voltage. However, the battery voltage must be reflected in the CONTROL ELEMENTS ÖØ PHASE COMPARISON ELEMENTSÖ 87PC SCHEME ÖØ 87PC CH1(2) RX VOLT settings, which define the acceptable voltage threshold received from the PLC.The L60 communications outputs are MOSFETs and inputs are implemented with optocouplers, excluding any galvanicconnection between PLC connections and the relay boards.Figure 3–24: L60 TO PLC CONNECTIONS FOR A TWO-TERMINAL LINEThe communications circuitry has the following characteristics for the transmitter and receiver.Transmitter characteristics:Operating voltage range: 0 to 300 V DC (typical points: 15 V, 48 V, 125 V, 250 V)Output current limitation: 100 mA (maximum), 30 mA (nominal)Receiver characteristics:Input voltage range: 0 to 300 V DCInput impedance: 25 kΩInput current: 10 mA at 250 V, 5 mA at 125 V, 2 mA at 48 V831784A1.CDRCOMMS INTERFACE INPUTS/OUTPUTS~~~~~~~~~~~~BATT+Tx1PTx1NTx Positive Ch 1BATT-Rx1PRx1NBATT+Tx2PTx2NBATT-Rx2PRx2NL60STATIONBATTERYPLCRx Positive Ch 1Tx Negative Ch 1Rx Negative Ch 1Common (+) Ch 1Common (-) Ch 1COMMS INTERFACE INPUTS/OUTPUTS~~~~~~~~~~~~5a5b5c6a6b6c7a8a7b8b7c8cBATT+Tx1PTx1NTx Positive Ch 1BATT-Rx1PRx1NBATT+Tx2PTx2NBATT-Rx2PRx2NL60STATIONBATTERYPLCRx Positive Ch 1L60 Comms 1Single-phaseComparison5a5b5c6a6b6c7a8a7b8b7c8cL60 Comms 2Dual-phaseComparison
