truckin : why 24 volt?

why 24 volt?
Post by truckin on Jun 25, 2006, 10:18am

Just wondering why the military uses a 24 volt system. Reliability, better for starting in cold weather?

Thanks,
Brad

Re: why 24 volt?
Post by k8icu on Jun 25, 2006, 10:29am

Yep basically you've got the idea. At the end of WWII the army wanted to standerdize the voltage on the military trucks. During WWII they had 12V and 6V and what have you trucks. Also positive ground and negitive ground. They wanted to simplify the system to one voltage. Also the development of the waterproof/radio suppression ignition system that came out on all M serries vehicles worked better on 24V. The cold starting properties were better and the commo/radio gear needed the higher voltage at the time for the plate and filiment supplies for the tubes. So these many factors lead to the system we have today. Also something to do with wire sizes and the higher voltage.
Funny thing is the civilian market is thinking of going to 24 or even 48 volt cars today.

Re: why 24 volt?
Post by hiker on Jun 25, 2006, 1:38pm

Great explanation k8icu.

Re: why 24 volt?
Post by mikel on Jun 25, 2006, 2:12pm

Higher voltage means a lower amperage to do the same work - You can get away with wires with a smaller cross-section.

Re: why 24 volt?
Post by brute4c on Jun 29, 2006, 10:03am

and the smaller wire means less weight and less copper used...can be a critical metal in war time...

Re: why 24 volt?
Post by truckin on Jul 3, 2006, 1:55pm

Thanks for all the replies, I've always wondered why they picked an oddball system.

Brad

Re: why 24 volt?
Post by brute4c on Jul 3, 2006, 2:04pm

The stuff I have read online says that all the big auto companies are looking at going to a new 36 volt standard....to save weight and wire, etc. Also ccuts the amps on them high output alternators...

Re: why 24 volt?
Post by k8icu on Jul 3, 2006, 9:52pm

not to mention all the gizmos they are running in cars today. Even the standards use more power than they did before. Higher voltage ignition systems, halogen super bright lights, computer systems for everything from the engine to braking to climate controll. Plus GPS, Navigation systems, killer audio/dvd/video game systems with LCD pannels etc. Need a lot more amps these days then the old MPGPW did....:)

Re: why 24 volt?
Post by truckin on Jul 4, 2006, 11:09pm


Quote: <TABLE class=bordercolor cellSpacing=1 width="90%"><TBODY><TR><TD width="100%"><TABLE class=quote cellSpacing=0 cellPadding=2 width="100%"><TBODY><TR><TD width="100%">The stuff I have read online says that all the big auto companies are looking at going to a new 36 volt standard</TD></TR></TBODY></TABLE></TD></TR></TBODY></TABLE>

Hate to think what those batteries will cost
But the whole car should be junk before the battery dies right?

Brad