3-34 G30 Generator Protection System GE Multilin3.3 DIRECT INPUT/OUTPUT COMMUNICATIONS 3 HARDWARE3The interconnection for dual-channel type 7 communications modules is shown as follows. Two channel modules allow fora redundant ring configuration. That is, two rings can be created to provide an additional independent data path. Therequired connections are: UR1-Tx1 to UR2-Rx1, UR2-Tx1 to UR3-Rx1, UR3-Tx1 to UR4-Rx1, and UR4-Tx1 to UR1-Rx1for the first ring; and UR1-Tx2 to UR4-Rx2, UR4-Tx2 to UR3-Rx2, UR3-Tx2 to UR2-Rx2, and UR2-Tx2 to UR1-Rx2 for thesecond ring.Figure 3–33: DIRECT INPUT AND OUTPUT DUAL CHANNEL CONNECTIONThe following diagram shows the connection for three UR-series relays using two independent communication channels.UR1 and UR3 have single type 7 communication modules; UR2 has a dual-channel module. The two communication chan-nels can be of different types, depending on the Type 7 modules used. To allow the direct input and output data to cross-over from channel 1 to channel 2 on UR2, the DIRECT I/O CHANNEL CROSSOVER setting should be “Enabled” on UR2. Thisforces UR2 to forward messages received on Rx1 out Tx2, and messages received on Rx2 out Tx1.Figure 3–34: DIRECT INPUT AND OUTPUT SINGLE/DUAL CHANNEL COMBINATION CONNECTIONThe inter-relay communications modules are available with several interfaces and some are outlined here in more detail.Those that apply depend on options purchased. The options are outlined in the Inter-Relay Communications section of theOrder Code tables in Chapter 2. All of the fiber modules use ST type connectors.842007A3.CDRTx1UR 1Tx2Rx1Rx2Tx1UR 2Tx2Rx1Rx2Tx1UR 3Tx2Rx1Rx2Tx1UR 4Tx2Rx1Rx2842013A2.CDRChannel 1Channel 2Tx1UR 2Tx2Rx1Rx2TxUR 1RxTxUR 3Rx
