GE N60 Instruction Manual page 60

DIRECT INPUT AND OUTPUT COMMUNICATIONS CHAPTER 3: INSTALLATION
The communications channels are normally connected in a ring configuration, as shown in the following figure. The
transmitter of one module is connected to the receiver of the next module. The transmitter of this second module is then
connected to the receiver of the next module in the ring. This is continued to form a communications ring. The figure
illustrates a ring of four UR-series relays with the following connections: UR1-Tx to UR2-Rx, UR2-Tx to UR3-Rx, UR3-Tx to
UR4-Rx, and UR4-Tx to UR1-Rx. A maximum of 16 UR-series relays can be connected in a single ring.
Figure 3-21: Direct input and output single-channel connection
3
The interconnection for dual-channel type 7 communications modules is shown as follows. Two-channel modules allow for
a redundant ring configuration. That is, two rings can be created to provide an additional independent data path. The
required connections are: UR1-Tx1 to UR2-Rx1, UR2-Tx1 to UR3-Rx1, UR3-Tx1 to UR4-Rx1, and UR4-Tx1 to UR1-Rx1 for 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 the second ring.
Figure 3-22: Direct input and output dual-channel connection
3-22 N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL