Standby generator

A standby generator is a generating set held in reserve and arranged for automatic start to pick up the electrical load when a running set trips or the bus undervoltage protection operates. It auto-starts, comes up to speed, synchronizes, and accepts load to prevent a blackout, distinct from the dedicated emergency diesel generator that feeds the emergency switchboard under SOLAS Ch II-1 Reg 42 and 43. Classification rules require automatic standby start and load transfer on ships with unattended machinery spaces, so propulsion and steering survive the loss of one generator without operator action.