2-14 N60 Network Stability and Synchrophasor Measurement System GE Multilin2.2 SPECIFICATIONS 2 PRODUCT DESCRIPTION22.2.8 COMMUNICATIONSRS232Front port: 19.2 kbps, Modbus ® RTURS4851 or 2 rear ports: Up to 115 kbps, Modbus ® RTU, DNP 3Typical distance: 1200 mIsolation: 2 kV, isolated together at 36 VpkETHERNET (FIBER)The UR-2S and UR-2T only support 100 Mb multimodeETHERNET (10/100 MB TWISTED PAIR)Modes: 10 MB, 10/100 MB (auto-detect)Connector: RJ45SNTP clock synchronization error: <10 ms (typical)ETHERNET SWITCH FIBER OPTIC PORTSMaximum fiber segment length calculation:The maximum fiber segment length between two adjacentswitches or between a switch and a device is calculated as fol-lows. First, calculate the optical power budget (OPB) of eachdevice using the manufacturer’s data sheets.where OPB = optical power budget, P T = transmitter output power,and P R = receiver sensitivity.The worst case optical power budget (OPB WORST ) is then calcu-lated by taking the lower of the two calculated power budgets, sub-tracting 1 dB for LED aging, and then subtracting the total insertionloss. The total insertion loss is calculated by multiplying the num-ber of connectors in each single fiber path by 0.5 dB. For example,with a single fiber cable between the two devices, there will be aminimum of two connections in either transmit or receive fiberpaths for a total insertion loss of 1db for either direction:The worst-case optical power budget between two type 2T or 2Smodules using a single fiber cable is:To calculate the maximum fiber length, divide the worst-case opti-cal power budget by the cable attenuation per unit distance speci-fied in the manufacturer data sheets. For example, typicalattenuation for 62.5/125 μm glass fiber optic cable is approxi-mately 2.8 dB per km. In our example, this would result in the fol-lowing maximum fiber length:The customer must use the attenuation specified within the manu-facturer data sheets for accurate calculation of the maximum fiberlength.ETHERNET SWITCH 10/100BASE-T PORTSConnector type: RJ45MAXIMUM 10 MBPS ETHERNET SEGMENT LENGTHSUnshielded twisted pair: 100 m (328 ft.)Shielded twisted pair: 150 m (492 ft.)MAXIMUM STANDARD FAST ETHERNET SEGMENT LENGTHS10Base-T (CAT 3, 4, 5 UTP): 100 m (328 ft.)100Base-TX (CAT 5 UTP):100 m (328 ft.)Shielded twisted pair: 150 m (492 ft.)PARAMETER FIBER TYPE10MB MULTI-MODE100MB MULTI-MODE100MB SINGLE-MODEWavelength 820 nm 1310 nm 1310 nmConnector ST ST SCTransmit power –20 dBm –20 dBm –15 dBmReceiver sensitivity –30 dBm –30 dBm –30 dBmPower budget 10 dB 10 dB 15 dBMaximum inputpower–7.6 dBm –14 dBm –7 dBmTypical distance 1.65 km 2 km 15 kmDuplex full/half full/half full/halfRedundancy yes yes yesOPB P T MIN( ) P R MIN( )–=Total insertion loss number of connectors 0.5 dB×=2 0.5 dB×= 1.0 dB=OPB WORST OPB 1 dB (LED aging)– total insertion loss–=10dB 1dB– 1dB– 8dB=Maximum fiber length OPB WORST (in dB)cable loss (in dB/km)-------------------------------------------------------=8 dB2.8 dB/km---------------------------= 2.8km=
