Boosting a 24 volt system

[Skyrider]

Stupid question but how do you boost a vehicle with two 12 volt batteries???

[canucksafari]

With two boost vehicles / batteries.

[The Dude]

My suggestion, get one of those Crappy tire boost packs (or equivalent) and keep it as your "second vehicle" Then all you need is to find someone to give you a boost on one of your batteries and use the boost pack on the other.

Or you need to find two cars to boost and hook up as normal.

I bought two small battery chargers and I hook them both up at the same time and charge like you would with a normal 12V system (one to each battery)

OR You could just have good friends that all have 24V systems...there's three of us on my block

[canucksafari]

Booster packs are a good idea but you would need two of them and to hook them up in series and then to the 24V + post and another to the engine block. Other than that two sets of boost cables. I have CAA but wonder if they would send two trucks (as long as I am not in the bush). However, I think that is their problem.

[Skyrider]

Thanks.

[st1age]

I have caa (AAA, for you americans), told them I needed 24v jump and they said it was no trouble, but sent a 12v guy who had no idea what he was doing... After he left we found two 12v batteries and hooked em up and it fired right up.

[TwoThirtyDirty]

2nd post in this thread says it best

http://forum.ih8mud.com/diesel-tech-24-volts-systems/189937-yet-another-newbie-questions.html

[jcolvin]

Originally Posted by canucksafari

Booster packs are a good idea but you would need two of them and to hook them up in series and then to the 24V + post and another to the engine block. Other than that two sets of boost cables. I have CAA but wonder if they would send two trucks (as long as I am not in the bush). However, I think that is their problem.

I don't think you'd need to hook them up in series. If you have two booster packs just hook one up to each battery. Those things often have electonics in them and they probably will get confused if you hook them up in series.

[Greg_B]

Originally Posted by Skyrider

Stupid question but how do you boost a vehicle with two 12 volt batteries???

http://forum.ih8mud.com/diesel-tech-24-volts-systems/115726-jumping-24v-12v.html

and http://forum.ih8mud.com/diesel-tech-24-volts-systems/57213-charging-24v-system.html

hth's

gb

[brownbear]

Originally Posted by canucksafari

With two boost vehicles / batteries.

NO


IF you do this the second vehicle will get 24 volts into his systems. You have to be sure his batteries are disconnected.

Best bet if you only have one vehicle to help boost you is to disconnect your batteries and connect each one to his battery and charge for 5-10 mins with their truck running. Then switch to the other battery.

If you try to boost 12 volts(from good vehicle) to your 24 directly go to the second battery and have his truck off(good vehicle). Ignition off etc.

If your system is low voltage, say 18-19 and won't crank his battery might bring you up a few volts and give the amps needed to get it started.

CAA or AAA sometime dispatch tow trucks that have 24 volt boosters. Ask for it.

[caddyles]

What do you mean by boost? I guess I don't speak Canadian very well... I think you are refering to a "jump" as we call it in the U.S., as to which I cannot help, however I've been having low battery problems myself lately and I just use a single 12v charger hooked up to each battery individually for about 20 minutes apiece (I try to keep the time the same so they end up equally charged) and this is working for me. Last night I had to do this, and for shis and giggles I put my volt meter on the battery that wasn't being charged to see if any juice trickled over to it while the other was being charged, (I'm new to this 24 volt deal too, and dont know much about how it works) and the unhooked battery gets no juice while the other is being charged, so why couldn't you jump or boost one battery at a time from a 12 volt car? Seems like it'd work, but dont take this as good solid advice, as I don't know for sure.

[caddyles]

To add to my prior message:
I must point out that I hook directly up to the battery I am charging, each battery is 12 volt UNLESS you tried charging the first battery (ungrounded) by hooking up to the positive terminal and then hooking up to the truck, you're at that point hooking up to 24 volts as the juice from the second battery is now combined with that of the first, hence frying your donor vehicle or perhaps your 12 volt charger. Even after your cruiser fires up and is running on its own charging system I dont see how you could fry a donor vehicle as long as your hooked directly up to just one battery at a time, just dont ground it to the vehicle, at that point, your 24 volts.

[canucksafari]

I must be dense (according to SWMBO that is a distinct possibility) or electrically challenged. Okay, I have 12V at the terminals on each battery, right? It isn't until I use the engine or frame as the ground for the high side that my meter registers 24Vs. So, if I connect both vehicles/batteries battery to battery, then it still only 12V to 12V on each vehicle and battery, no?

Second, to avoid the possibility of H gas exploding, I think first hooking up the leads on the 24V vehicle and then last the ground leads on the charging vehicles to the frame/engine would minimize this problem.

Anyways, It isn't likely that I will leave my lights on. The dummy buzzer is nearly as loud as my pathetic JDM horn.

Originally Posted by brownbear

NO


IF you do this the second vehicle will get 24 volts into his systems. You have to be sure his batteries are disconnected.

Best bet if you only have one vehicle to help boost you is to disconnect your batteries and connect each one to his battery and charge for 5-10 mins with their truck running. Then switch to the other battery.

If you try to boost 12 volts(from good vehicle) to your 24 directly go to the second battery and have his truck off(good vehicle). Ignition off etc.

If your system is low voltage, say 18-19 and won't crank his battery might bring you up a few volts and give the amps needed to get it started.

CAA or AAA sometime dispatch tow trucks that have 24 volt boosters. Ask for it.

[brownbear]

to explain myself further...

if you were to boost with two vehicle to your one 24 volt truck. You would have to connect one booster cable from your trucks ground point to the first trucks negative post. Then from the first trucks positive post you would connect it to the second trucks negative post. Then from the seconds truck positive post to your dead second battery(high side) positive post.

This would give you a 24 volt boost. But the second truck would get 24 volts at his positive post. So if he had his ignition on he would fry something. So his truck has to be off. The first truck could be running.


I think this procedure is dangerous. Too many chances of a fawk up.


If you were to have one truck give you a boost with 12 volts, I would have him only hook up to your first battery on the low side. Then just + to + and - to -. Do it like a standard boost. Do not connect the + to your high side. He will get 24 volts.

[lowenbrau]

Brownbear, I rarely get to tell you this but you're wrong. Its a bird on a wire thing. If you did this whole procedure on a aircraft carrier with a conveyer belt and connected the ocean to a nuclear station and energized the whole thing with 1.21 gigawatts you'd still only have 12V difference between the red and black leads on your cables.

Its fine to use two trucks. Its also generally effective to just use one 12V truck connected to your low side battery (it tends to be the dead one)

[brownbear]

Ok.... I don't mind being wrong but lets forget the dead vehicle is there at all(or the nuclear reactor) if I park two 12 volt vehicles side by side and hook there batteries in series would the second battery have 24 volts? Or would that only happen if you connected the ground wire from the first vehicle to the second.

With you saying the "bird on the wire" it makes me think. If the second vehicle doesn't get grounded to the dead car would it only see 12 volts on the positive post?

[lowenbrau]

On the first point. What do you mean in series? + of rig A to - of rig B and then what? From the - of rig A and the + of rig B you could now boost a 24V truck.

On the second point, Yeah, right. Don't let the bumpers touch. As long as the rigs are isolated having +12V on the black clamp and +24v on the red one (relative to the chassis of the first rig) is fine

[brownbear]

I series... meaning a series circuit. The description you say above is a series/parallel circuit. Vehicle A and B in series with Vehicle C(dead 24 one) connects in parallel to both A and B.

So if A and B are in series and nothing grounds them together or they touch C it would work.

So if you own a 24 volt truck I guess you need to buy two booster cables and peel the haves apart to have three leads to work with.

[lowenbrau]

I have had a lot of 24 Volt trucks and a fair number of dead batteries over the years and you can nearly always boost them with a 12v rig. On the few times that you can't you hook up the towstap and pull start them.

[canucksafari]

Okay, I will admit defeat to SWMBO. I am completely confused now, I think, well maybe.

Lawenbrau, I will first try to play it safe with just jumping from the low side battery if ever needed. BB, if that doesn't work and a push start is not an option, then I'll risk nuclear meltdown as I had origonally planned it.

[brownbear]

LOL!

Let's put it this way..... I'm dabbling in theory, Lowenbrau is speaking experience.....

[jonb96150]

Well,
I don't theory, but i have put jumper cables from my 12v rig to one battery of my 24v rig to start the 24v rig with no problems.
i just needed a few extra amps for the 24v rig to start and it did. that was a while ago and both rigs are fine.
hth

[motorcoach123]

Originally Posted by jonb96150

Well,
I don't theory, but i have put jumper cables from my 12v rig to one battery of my 24v rig to start the 24v rig with no problems.
i just needed a few extra amps for the 24v rig to start and it did. that was a while ago and both rigs are fine.
hth

That might work if the 24V vehicle's batteries are only slightly low....say 20V or so. But if you have a 24V vehicle that has totally flat batteries you will need a 24V donor to boost ('jump' if you are south of the border) start...unless you have lots of time, then disconnect the two from battery each and 12V charge each battery individually until they are strong enough. FWIW

gord

[brownbear]

Originally Posted by motorcoach123

boost ('jump' if you are south of the border)
gord

So you call them jumper cables at the store? When we go to buy them the package says "booster cables".....