The main purpose of the synchronism and energizing check SECRSYN1 is to provide control over the closing of the circuit breakers in power networks and prevent the closing if the conditions for synchronism are not fulfilled. The energizing function allows closing, for example, when one side of the breaker is dead.
SECRSYN1 measures the bus and motor terminal voltages and compares them to set conditions. When all the measured quantities are within set limits, the SYNC_OK output is activated for allowing closing or closing the circuit breaker. The SYNC_OK output signal is connected to the ENA_CLOSE input of CBXCBR1 through control.
To ensure the validity of the measured voltages on both sides, Bus MCB Open Position X115-BI8, Line MCB Open Position X105-BI7 and FUSEF_U from SEQSPVC1 are connected to block SECRSYN1.
The operating signals from the protections and an external trip X105-BI4 via MVGAPC1 are connected to signal output X115-SO2 and the trip output contact X100-PO3 via the corresponding Master Trip TRPPTRC1. The opening control commands to the circuit breaker from the local or remote CBXCBR1_EXE_OP are connected directly to the output X100-PO3.
TRPPTRC1 provides the lockout/latching function, event generation and the trip signal duration setting. If the lockout operation mode is selected, SPCGAPC1_O10 is connected to the RST_LKOUT input of the Master Trip to enable external reset with a push button.
There are two types of disconnector and earthing switch blocks available. DCSXSWI1...4 and ESSXSWI1...3 are status-only type, and DCXSWI1...4 and ESXSWI1…3 are controllable type. By default, the status-only blocks are connected in the standard configuration logic. If a controllable operation is preferred, the controllable type of disconnector and earthing switch blocks can be used, instead of the status-only type. The connection and configuration of the control blocks can be made using PCM600.
The binary inputs 1 and 2 of the card X130 are used for busbar disconnector 1 DCSXSWI1 position indication. The binary inputs 3 and 4 of the card X130 are used for busbar disconnector 2 DCSXSWI2 position indication.
| Primary device position | Input to be energized | |
|---|---|---|
| X130-BI1 | X130-BI2 | |
| Busbar disconnector 1 closed | ● | |
| Busbar disconnector 1 open | ● | |
| Primary device position | Input to be energized | |
|---|---|---|
| X130-BI3 | X130-BI4 | |
| Busbar disconnector 2 closed | ● | |
| Busbar disconnector 2 open | ● | |
The binary inputs 7 and 8 of card X110 are designed for the position indication of the earthing switch.
| Primary device position | Input to be energized | |
|---|---|---|
| X115-BI5 | X115-BI6 | |
| Earthing switch closed | ● | |
| Earthing switch open | ● | |
The circuit breaker closing is enabled when the ENA_CLOSE input is activated. The input can be activated by the configuration logic, which is a combination of the position statuses of related primary equipment (disconnector and earthing switch), the condition of the circuit breaker (CB gas pressure alarm, CB spring charged), and the Master Trip logics. The OKPOS output from the DCSXSWI block defines if the disconnector is definitely either open or close. This, together with non-active trip signal activates the ENA_CLOSE signal to the circuit breaker control function block. The open operation is always enabled.
The circuit breaker closing is blocked when the BKL_CLOSE input is activated, which is connected to motor restart inhibit logic. When all conditions of the circuit breaker closing are fulfilled, the CLOSE_ENAD output of the CBXCBR1 is activated and PO1 output X100-PO1 is closed.
Emergency stop signal to AU_OPEN input of CBXCBR1 via MVGAPC1 is used to open the breaker by one push button through SPCGAPC1_O8 or by a binary input X105-BI5. Emergency start signal to AU_CLOSE input of CBXCBR1 via MVGAPC1 is used to close the breaker by one push button through SPCGAPC1_O16 or by a binary input X105-BI6.
One push button can be used through SPCGAPC1_O11, which is connected to SYNC_ITL_BYP input of the CBXCBR1, to ignore the status of ENA_CLOSE input However, the BKL_CLOSE input signals are not bypassed with the interlocking bypass functionality as they always have a higher priority.
The circuit breaker condition monitoring function SSCBR1 supervises the circuit breaker status based on the binary input information connected and the measured current levels. SSCBR introduces various supervision methods. The corresponding supervision alarm signals are routed to LED 8.
The signal outputs from the relay are connected to give dedicated information.
- Start of any protection function X100-SO1
- Operate of any protection function X100-SO2
TPGAPC function blocks are used for setting the minimum pulse length for the outputs. There are four generic timers TPGAPC1…4 available in the relay. The remaining ones, which are not described in the functional diagram, are available in PCM600 for connection where applicable.