Thread Content
First, let’s take a look at the distribution of the interfaces on the backplane. There are four areas in total, namely X1, X2, X3, and X4. X1 is the analog signal sampling board, which is responsible for collecting current and voltage signals from the incoming lines and buses. The X2 board includes a device power interface, signal output port, 485 communication port, remote printing interface, and GPS clock. X3 is a remote signaling/output board that includes input and output channels, while X4 is an expansion board that allows for the addition of more input and output channels depending on the specific requirements of the installation site. Definition of the analog signal acquisition ports: Depending on the wiring of the power distribution system, different analog signals are acquired. In the case of a two-input single-bus structure, 5 voltage values and 6 current values are collected, namely the currents of phases A, B, and C of the first input (Ia1, Ib1, Ic1), the currents of phases A, B, and C of the second input (Ia2, Ib2, Ic2), the voltage of the first input (U1), the voltage of the second input (U2), and the bus voltages (Uab, Ubc, Uca). In the bus coupler mode, that is, a double-input single-bus sectionalized structure, 8 voltage values and 9 current values are collected. They are the currents of phases A, B, and C of the first feed line (Ia1, Ib1, Ic1), the currents of phases A, B, and C of the second feed line (Ia2, Ib2, Ic2), the currents of phases A, B, and C of the bus bar connection, the voltage of the first feed line (U1), the voltage of the second feed line (U2), the voltage of bus section 1 (Uab1, Ubc1, Uca1), and the voltage of bus section 2 (Uab2, Ubc2, Uca2). Definition of the main input ports: Ports 323–327 are used for connecting the incoming lines and the auxiliary contacts of the busbar circuit breakers, in order to monitor the status of the switches; ports 328–329 are used to connect to the higher-level main protection systems, enabling the activation of such protection. 330-331 receive manual start command. 332 Access device lock command. 333 is the reset command for access devices; 334 is the locking command for access exits. 335-336: Access protection lockout command; 337: Access bus PT maintenance lockout command. 338 is the common terminal for input signals. Definition of the main output ports: 301-316 are used for the opening and closing commands of Input Line 1, Input Line 2, and the busbar switch; 317-318 are used for the trip commands of the busbar protection; 319-322 are used for the acceleration commands after starting Input Line 1 and Input Line 2. 206-210 Access device fault commands. 211-212 access alarm signals, usually due to backup power failure or PT disconnection. 213-218 Access device operation signals, including switching operations, locking operations, and protection operations.