Q5. Sketch and describe an arrangement for automatic connection of emergency batteries upon loss of main power, include in your answer:
(a) Means of obtaining d.c. charging supply from a.c. mains;
(b) A method of maintaining charge on lead acid batteries;
(c) The arrangement to check that batteries operate at loss of main power
(d) The length of time for which emergency batteries of passenger and cargo ships must provide power.