ABB RELION 670 Series Technical Manual page 766

Section 14
Control
The voltage selection function, selected voltages, and fuse conditions are used for the
Synchronism check and Energizing check inputs.
For the disconnector positions it is advisable to use (NO) a and (NC) b type contacts to supply
Disconnector Open and Closed positions but, it is also possible to use an inverter for one of the
positions.
If breaker or disconnector positions not are available for deciding if energizing is allowed, it is
considered to be allowed to manually energize. This is only allowed for manual energizing in
breaker-and-a-half and Tie breaker arrangements. Manual energization of a completely open
diameter in 1 1/2 CB switchgear is allowed by internal logic.
Voltage selection for a single circuit breaker with double busbars
The setting
double busbars. This function uses the binary input from the disconnectors auxiliary contacts
BUS1_OP-BUS1_CL for Bus 1, and BUS2_OP-BUS2_CL for Bus 2 to select between bus 1 and bus 2
voltages. If the disconnector connected to bus 1 is closed and the disconnector connected to bus 2
is opened the bus 1 voltage is used. All other combinations use the bus 2 voltage. The outputs
B1SEL and B2SEL respectively indicate the selected Bus voltage.
The function checks the fuse-failure signals for bus 1, bus 2 and line voltage transformers. Inputs
VB1OK-VB1FF supervise the MCB for Bus 1 and VB2OK-VB2FF supervises the MCB for Bus 2. VL1OK
and VL1FF supervises the MCB for the Line voltage transformer. The inputs fail (FF) or healthy (OK)
can alternatively be used dependent on the available signal. If a VT failure is detected in the
selected voltage source an output signal VSELFAIL is set. This output signal is true if the selected
bus or line voltages have a VT failure. This output as well as the function can be blocked with the
input signal BLOCK. The function logic diagram is shown in figure 404.
760
CBConfig selected for Double Bus activates the voltage selection for single CB and
1MRK 502 066-UUS B
M14838-3 v9
Technical manual