A self-contained standby generator automatically supplying essential electrical power to safety systems if the main supply fails.
The emergency generator must be capable of operating for at least 18 hours on cargo ships and 36 hours on passenger ships at the design load. Monthly no-load test runs and annual load tests are required by SOLAS and class rules, with results recorded in the deck and engine-room logs. Engineers must verify that the starting arrangement — usually automatic and manual battery start — is functional and that the transition contactors and preferential trip systems operate correctly. Port state control inspectors routinely test emergency generator start-up as part of safety equipment inspections and may detain vessels where the system is found to be non-functional.
Authoritative source: SOLAS Chapter II-1 (Construction — Subdivision and stability) ↗
Source: SOLAS Chapter II-1, Regulation 43
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