Advantages of 24v

[cranetruck]

........There was a lot of talk in the trade magazines a few years ago about moving to 48V systems. Lots of silicon was developed for a market that never materialized.

Higher voltage means less current and less copper, I think the trend still is to go to a higher voltage in our cars and trucks, maybe even 36 or 42 volts....

 

[m16ty]

your always supposed to disconnect it anyways, to protect the electronics.

What I was talking about is troubleshooting the elecrtical. Say your brake light quit working and you take the light apart to make sure it's getting power to it with a test light or volt meter. You're going to have to be alot more carefull than you would for a 12 volt system. I see alot of "shade tree" mechanics getting fried.

 

[rockspider]

Does the controller see the same voltage that the glow plugs see? I thought the controller only handled switching the relay which would isolate the controller from the 24v.

I was thinking the same but have no definitive answer. Anybody knows a sure answer to this?

(see previous posts #13 #14 and #20)

Me too would like to get rid of the resistor and correlated snowball-destructive-effect and switch GP and relay to Hummvee 24v ones.
Any help?

 

[hobie237]

I've often wonder why the civilain world hasn't switched over to 24V especially in heavy trucks. 24V just turns a engine over much better and less amp draw on your electrical system.
I'm thinking the main reason tractor-trailers havn't switched is because they usually don't stay hooked to the same trailer. If some company came out with a 24V truck they could only pull a trailer with 24V lights so you would have to switch the bulbs on the trailers you pull. Problem is that there are milions of trialers still out there that are still 12V so if you took a load some place and dropped your trailer to pick up another one you would have to swap the bulbs before you could get on the road.

Meh, you could just run a dual voltage system (like on the CUCV) to run 12v bulbs without issue, and without regard to the voltage used for the starter. I'd say the bigger issue is parts and components commonality and expense. The more obscure the component, the more expensive it is, so it's easier to keep using the old stuff than having to develop a bunch of new stuff.

Same thing about why the US is still on 120v house current when the rest of the world is on 240v.



As a more general response, the advantage of 24v is that the starter just plain works better. Then again, there are plenty of civilian diesel trucks out there, 6.2L and otherwise, that start just fine with a 12v starter. Sure, the 24v is better, but do you need something better if something else is sufficient for the task at hand? Dunno. Same thing with winches, unless of course we're getting into *REALLY* extreme 4x4 stuff, but that's not what's generally discussed on this forum, so I'll assume that a CUCV isn't being used for extreme rockcrawling or whatever.

I think most people retain the 24v system because either a) it's cool, b) it's original military spec and they want to keep the truck that way or c) it's working just fine so there's no point fixing what ain't broke.

I fall under option c. I guess if it gives me trouble I'll keep it 24v if the parts are available at a price I'm willing to pay at the time I need them (and LOCAL, since I've already lost $210 to one jackass on this forum)- since I know they most likely won't be, I'll most likely go ahead and convert to 12v at that time.

 

[maritimer]

i like it cause its cool, its military spec, and i can boost my moms boy freinds boat, crossing my fingers i havent had to try and find any 24v starters here yet

 

[jwaller]

I know my hmmwv 6.2 starts a heck of a lot better (quicker spining) than my buddies cucv.

 

[hobie237]

Are you implying that your buddy's CUCV is 12v? Has his ever *not* started when he needed it to? Are his batteries older than yours? I'd think a 24v HMMWV 6.2 and 24v CUCV 6.2, holding all else constant (like battery health) would start about the same.

 

[mangus580]

Dont the HMMWV's use the gear reduction starter now?

 

[hobie237]

They may, I have no idea. Obviously there's some other variable at play, because otherwise the two engines should start the same.

 

[saddamsnightmare]

December 11th, 2008.

The military had a reason for the 6/12V systems in WW2, and the 24VDC systems after that..... It's what the NATO trucks use, for its size it's a simpler, more powerful system, and for the diesels, it gives you some reserve for cold starts without ether.
On the railroad our headlights and auxilliaries were 32, then 64, and finally 75VDC, and the passenger cars (railroad) went 32/64/75 then 110 VDC before the conversions to HEP, and it was done to reduce ampereage at a given load.
We would benefit from 24 or even 48 VDC electricals on most vehicles today as it would physicially reduce the size of the starters and generators for a given load. I'll have to check my manual, but I belive the 1963 Swiss S404.114 Unimogs use a 3 phase AC alternator, (Mike Pop can weigh in here for me.....!)but the output is reduced to 24VDC for the batteries, lights and such. The Unimogs originally used the same slave plugs as the deuces, mine has none, but the later ones used the NATO standard slave plugs as we do today on the more modern military vehicles. Model T Fords varied from 7 to 24 VDC on the magnetos, and yes, they could curl your hair if you screwed up (Mechanical DArwinism)! Ask anyone whos been shocked by a Model T ignion coil.....
I'd vote for 24VDC, as I've had less trouble with it overall.....
Just my .02 worth.....


Sincerely,

Kyle F. McGrogan

 

[Chevytruck]

Why cant they put the standard voltage 48 volts and put a converter on so that the trailers run at 12 volts

that sounds like a simple thing to do

 

[dependable]

My civy Mack 1961 B-61 with a mack 673 was 24 v start. I'd still have it but for rust.

 

[jwaller]

Dont the HMMWV's use the gear reduction starter now?

I dont know but I do know my hmmwv starter in HUGE. as in about the same size as the one on my 5T. nothing like the cucv's.