Battery systems are automatically connected upon loss of main supply and function as a transitional source for at least 30 minutes before the generator is started.
Power available for emergencies must be sufficient to operate certain essential services simultaneously for up to 18 hours. These are:
a) Emergency lights
b) Navigation lights
c) Internal communication equipment
d) Manual fire alarms
e) Emergency fire pump
O Steering gear
g) Navigational aids
Transitional batteries are required to supply 30 minutes of power for emergency lighting, and general alarm. fire-detection and alarm system, communication equipment, and navigation lights.
Automatic Operation of Emergency Generator
- Starting of the emergency generator prime mover is often automatic. The run-up is initiated by an electrical sensing relay which monitors the normal mains power supply.
- Failing mains frequency or voltage causes, the sensing relay to initiate “start-up” of emergency diesel via the control circuit by closing contact R.
- The control circuit operates on power from the emergency battery. The prime mover may be electrically cranked from its own 24 V battery and starter motor or air-started from its own air reservoir fitted local to the generator engine.
- A manual start-up and shut-down may be initiated by pushing buttons in the emergency generator room.
