GE GEK 106168E manual Remote Communications, Operation Logic, DBF Breaker Failure Protection

2. OPERATION LOGIC

2.6. REMOTE COMMUNICATIONS

The relay has 2 serial gates and three connectors. Gate 1 can be reached from the front of the relay in connector 1 (PORT 1 connector) or from the rear (PORT 2 connector). The second gate can be reached from connector 3 (PORT 3 connector) which is located on the rear.

There are different models, each with a different physical connection for the PORT 3 connector (RS-232/RS-485 or fiber-optic). In the "RS232" models the three connectors are RS232. In the "RS232 and fiber-optic" models the PORT1 and PORT2 connectors are RS232 while the PORT3 connector is replaced by a fiber-optic connector.

The PORT 1 connector has priority over the PORT 2 connector and is selected when the DCD (Data Carrier Detect) signal is activated. Figure 8 shows how to make the connections to a personal computer.

Gate 1 (PORT 1 and PORT 2 connectors) and 2 (PORT 3 connector) are independent and the unit can serve them simultaneously.

The communications protocol is the same used for the rest of the GE digital protection systems and requires the use of the GE-LOCAL software. PORT 3 protocol can be chosen between M-LINK and ModBus RTU. The protocol is highly reliable and allows communication with different protection systems. It guarantees very efficient data transfer (especially for the oscillography and other large files) along with error detection and automatic communication recovery.

The status of the local/remote communication is indicated on the front of the unit by LED indicator 16 (the last LED in the right-hand column, according to the default configuration.) Local communication refers to communication via the keyboard/display (local display showing any information except for the initial DBF GENERAL ELECTRIC screen), or via communications gate 1 (PORT 1, PORT2 connectors), and remote communication refers to connection via gate 2 (PORT 3 rear connector).

Local and remote communications can exist at the same time, although there is only one possibility for changing settings and carrying out operations, since this can only be done with the communication which has priority (local communication) while the other is limited only to accessing information. When the local communication is interrupted, either by the disconnection of PORT 1 connector or because the HMI is on the initial screen (a situation which can be caused intentionally, or automatically if no key has been pressed for 15 minutes), the remote communication recovers the ability to modify settings and carry out operations.

16 DBF Breaker Failure Protection GEK-106168E