Page 715 - PPL-engelsk 2025
P. 715
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 715
