5-66 B30 Bus Differential System GE Multilin5.2 PRODUCT SETUP 5 SETTINGS55.2.16 TELEPROTECTIONPATH: SETTINGS PRODUCT SETUP TELEPROTECTIONThis option is available when an INTER-RELAY COMMUNICATIONS card is specified at the time of order-ing. With the option, direct inputs/outputs display by default. When you enable the teleprotection feature,direct I/O is not visible.Digital teleprotection functionality is designed to transfer protection commands between two or three relays in a secure,fast, dependable, and deterministic fashion. Possible applications are permissive or blocking pilot schemes and directtransfer trip (DTT). Teleprotection can be applied over any analog or digital channels and any communications media, suchas direct fiber, copper wires, optical networks, or microwave radio links. A mixture of communication media is possible.Once teleprotection is enabled and the teleprotection input/outputs are configured, data packets are transmitted continu-ously every 1/4 cycle (3/8 cycle if using C37.94 modules) from peer-to-peer. Security of communication channel data isachieved by using CRC-32 on the data packet.Teleprotection inputs/outputs and direct inputs/outputs are mutually exclusive – as such, they cannot be used simu-latneously. Once teleprotection inputs and outputs are enabled, direct inputs and outputs are blocked, and viceversa.• NUMBER OF TERMINALS: Specifies whether the teleprotection system operates between two peers or three peers.• NUMBER OF CHANNELS: Specifies how many channels are used. If the NUMBER OF TERMINALS is “3” (three-terminalsystem), set the NUMBER OF CHANNELS to “2”. For a two-terminal system, the NUMBER OF CHANNELS can set to “1” or“2” (redundant channels).• LOCAL RELAY ID NUMBER, TERMINAL 1 RELAY ID NUMBER, and TERMINAL 2 RELAY ID NUMBER: In installa-tions that use multiplexers or modems, it is desirable to ensure that the data used by the relays protecting a given lineis from the correct relays. The teleprotection function performs this check by reading the message ID sent by transmit-ting relays and comparing it to the programmed ID in the receiving relay. This check is also used to block inputs if inad-vertently set to loopback mode or data is being received from a wrong relay by checking the ID on a received channel.If an incorrect ID is found on a channel during normal operation, the TELEPROT CH1 ID FAIL or TELEPROT CH2 ID FAILFlexLogic™ operand is set, driving the event with the same name and blocking the teleprotection inputs. For commis-sioning purposes, the result of channel identification is also shown in the STATUS CHANNEL TESTS VALIDITY OFCHANNEL CONFIGURATION actual value. The default value of “0” for the LOCAL RELAY ID NUMBER indicates that relay IDis not to be checked. On two- terminals two-channel systems, the same LOCAL RELAY ID NUMBER is transmitted overboth channels; as such, only the TERMINAL 1 ID NUMBER has to be programmed on the receiving end. TELEPROTECTIONTELEPROTECTIONFUNCTION: DisabledRange: Disabled, EnabledMESSAGE NUMBER OF TERMINALS:2Range: 2, 3MESSAGE NUMBER OF COMMCHANNELS: 1Range: 1, 2MESSAGE LOCAL RELAY IDNUMBER: 0Range: 0 to 255 in steps of 1MESSAGE TERMINAL 1 RELAY IDNUMBER: 0Range: 0 to 255 in steps of 1MESSAGE TERMINAL 2 RELAY IDNUMBER: 0Range: 0 to 255 in steps of 1NOTE
