AC auxiliaries boards (AB) are designed for 0.4 KV electric power input and distribution, for power supply, protection, explicit or implicit redundancy of AC auxiliary consumers.
Auxiliaries boars provide as follows:
• receiving AC electric power from the transformers for the needs of power stations and substations.
• protection of consumers and outgoing lines against short-circuit and overload currents by circuit breakers.
• ground fault protection with built-in protection or circuit breakers.
• automatic transfer switch (automatic circuit breaker (ACB)) in case of unacceptable decrease or loss of voltage at one of inputs.
• automatic return to normal power supply mode (power supply circuit restoration (PSCR)) when input voltage is restored.
• circuit breaker status alarm.
• remote alarm of the emergency modes and circuit breaker states.
• transmission of information about the current electrical parameters of the three-phase power supply network and the status of circuit breakers in digital form via RS-485 interface to remote computer or to the top-level automated process control system (if necessary).
• energy consumed accounting.
• load current control at inputs and voltage on the bus bar sections.
