Page 714 - engelsk
P. 714

Aircraft general knowledge



                8.6.3    Batteries and generators


                Voltage is obtained from generators or batteries.




                8.6.3.1     Batteries


                A battery is made up of several elements. The battery produces voltage so that

                the engine can be started.




                The voltage from a battery is 12 or 24 volts

                DC.


                   -   12V batteries are in a 14V system

                   -   24V batteries are in a 28V system


                The capacity is measured in ampere-hours.




                Batteries can be connected in series so that

                the voltage is doubled.


                Batteries can also be connected in parallel so
                that the ampere-hours are doubled instead.





                In  the  figure  you  can  see  what  voltage  is

                obtained with a series connection and a parallel connection, respectively.




                8.6.3.2     Dynamo and alternator


                The  voltage  we  get  from  a  generator  or  alternator  (dynamo  or  alternating
                current generator) is basically different.


                An  alternator produces an Alternating Current (alternating voltage), which is

                converted to direct voltage via rectifiers (diodes).



             Flyveteori PPL(A)(UL)/LAPL             Henning Andersen, Midtjysk Flyveskole© 2025               714
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