Section 7 Electrical and control: approval

7.1.1 The electrical and control equipment should consider all potential failure mechanisms and it is to be demonstrated that no existing equipment or functionality will be degraded due to the modification.

7.2.1 Power supply and balance – the electrical power balance on board is not to be adversely affected by the ALS power demands. The electrical distribution system should be considered when determining the supply of the source power. For example, the system could be supplied from the bow thruster switchboard as these systems are unlikely to operate simultaneously. The electrical equipment of the ALS is to be suitably rated for the anticipated short circuits expected at the points of connection into the electrical system. The existing discrimination arrangements of the electrical protection are not to be adversely affected due to the installation of new circuit breakers or fuses connected into an existing electrical system.

7.2.2 Control system – the AHU would be considered as a blower during design appraisal with the applicable requirements applied. The unit should have the functionality to be stopped both locally and remotely. The electrical requirements for fire safety stops are to be provided locally and remotely in accordance with requirements for fire safety.

7.2.3 Hazardous areas – no air inlet, machinery or controls will be located in a gas hazardous area. If this cannot be achieved, then LR should be advised.

7.2.4 Cable penetrations – all penetrations are to be appropriate considering the penetrated structure and the designation of the corresponding spaces.

7.5.1 If considered necessary, a DAD is to be issued at the end of the design appraisal process.