Electric Systems

[uwochris]

Hey guys,



Can someone please explain to me why the voltage capacity of the electrical system is always very close, but always less than., the voltage of the battery? For example, a 12 V battery is generally found on a 14V electrical system, while a 24 V battery is found with a 28V electrical system.



I thought it had to do with the fact that the battery must be kept charged, however, I could not make much sense of that. Ie) it’s my understanding that the alternator/generator keeps the battery charged, while the battery supplies power to all the electrics. Is this wrong?



Thanks in advance,



Chris.

 

[A Squared]

Chris,

the Alternator or generator does both, it supplies electricity to the equipment and it keeps the battery charged. You can disconnect the battery form a running engine and the electrical equimpment will stll be supplied with electricity. the only time hte battery is suplying electricity is when the engine is stopped, or in periods of high load when the use exceeds the alternator's capacity. THe electrical system is necessarily higher votage than the battery to keep it charged. In order to make electrictity flow from the alternator (or generator) to the batery, it mush have a higher voltage than the battery.

 

[EagleRJ]

That is correct.

You can think of voltage as electrical pressure. If you want the electrons to flow from the alternator to the battery, the voltage of the alternator must be a little more.

If the alternator and the battery were both 12 volts, they would share the electrical load equally, and after a while the battery would be depleted.