Specifically, according to the changes, DNV GL states that
For all E0, AUT or AUT-nh vessels (built at any time) and all vessels constructed on or after 1998-07-01 where electricity is necessary for propulsion and steering, test of the automatic start and connection to the switchboard of the standby generator set shall be carried out.
Thus, if the vessel’s normal seagoing load is covered by a single generator, this test shall be conducted by shutting down the running generator, such as creating a blackout. For vessels where the normal seagoing load is covered by two or more generators, the test shall be conducted by shutting down one of the running generators.
DNV GL comments that restarting the machinery plant, following a blackout, is most of the time problematic, due to the incorrect system settings, crew unfamiliarity, empty or faulty UPS units or, not least, empty internal batteries on chipboards or PLCs.
To understand the issues and be sure that the vessel will be able to restore power after a blackout, DNV GL proposes testing the systems.
This test must therefore be carried out, and, importantly, it must be carried out correctly.
Moreover, simulating a blackout, as triggering the standby generator to come on line without shutting down the single generator as required, will not show all the hidden challenges and difficulties.
New steps for annual testing:
It is sometimes challenging to conduct a test as required. This is because oil and gas terminals don't allow vessels to immobilize, cargo operations are disrupted, the crew is afraid of damaging electronic equipment, etc.
In light of the challenges stated above, class attendance during the standby functionality test is no longer required, so that the testing can be conducted into a convenient hour.
DNV GL proposes that the test should be conducted in line with the written procedures which, for ships where the normal seagoing load is covered by a single generator, shall include a blackout.
The procedure should:
- Address the relevant items listed in the Appendix under Annex I: Guidelines for standby functionality test procedure. This procedure does not require class approval but should be presented to the attending surveyor for his/her acceptance.
Following, if the test successes, it should be reported to a log book entry, signed by the Chief Engineer and a copy or screenshot of the alarm log. If the test has not been conducted by the vessel at the time of the annual survey, or the operator simply wishes to conduct the test during the annual survey, this is still possible.
The test shall always be witnessed by class during renewal surveys on all vessels and during annual surveys for vessels where a poor condition and/or poor maintenance is registered.
DNV GL states.
By preparing test procedures and conducting tests prior to the annual surveys, vessels can limit the impact of annual surveys on the daily operations.