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Jump Packs 12 volt and 24 volt

whejdak

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I am curious if anyone has tried using two 12 volt jump packs in series to make a 24 volt jump pack?
There are a lot of 12 jump packs but only a few 24 volt packs. The 24 volt packs are a heck of a lot more expensive.
I was thinking about buying two of the 12 volt jump packs. This way when I only need to use one on a car I wouldn't have to lug the big 24 volt around.
When I need the 24 which is not all that often I could simply connect the two 12's in series and I'd have 24 pack. In addition, i could have one 12 for the pole barn and one 12 for my car.
When the 24 goes bad, I would loose the unit more then likely. If I had two 12's, chances of both going isn't likely, and I'd still have one left over.
I've been looking at the pricing and it seems like the 24 's are double the price of a 12. Not surprising for marketing techniques. I would by the lesser of amperage units (cheaper). When connected in series, I would have all the amp's I would need for my purposes.
 
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whejdak

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Ok, let me make this less complicated.

Anyone know why you can't connect two 12 volt Jump Packs in series to make 24 volt jump pack.
 
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whejdak

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It would seem to me, that if you can hook two batteries in series to get 24, why not to Packs?
You might be right about they not liking what I want to do with them. I've look hard and long on the internet. Found nothing about it.
 

RTM

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Because some electronics don’t like to play outside their range. Don’t know that either would limit you to 14v as a form of self protection for the pack. I suspect using a 12v pack and a good battery to get to 24v would not work either, but might be a way to check,


take a battery out of a vehicle,, take it and pack to truck, and hope the magic smoke stays inside everything.
 

WildBill

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I just tried it with two of my lithium jump packs, they have a little protection box inline on the cables that gets unhappy and won't let power through. I bet regular lead acid battery jump packs would work fine though, or if you bypassed the protection boxes on the cables. You can also buy the cable assemblies without the protection on amazon for cheap.
 
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micromind

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The jump-pacs I've seen have a simple mechanical switch between the battery and the clamps. They can be connected in series to get 24 volts.

If the 'switch' is any kind of an electronic thing, most likely they cannot be connected in series.
 
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whejdak

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I just tried it with two of my lithium jump packs, they have a little protection box inline on the cables that gets unhappy and won't let power through. I bet regular lead acid battery jump packs would work fine though, or if you bypassed the protection boxes on the cables. Youi can also buy the cable assemblies without the protection on amazon for cheap.
I agree with you on the lead acid batter jump packs. probably act similar to two batteries is series . I know these Lithium packs have power switches on them. Turning one on at a time, probably won't work nor switching to switch them both on at the same time.
I've contacted NOCO and waiting for an answer from them.
Interesting that you had two packs there to try. Thanks for the experiment.
 
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whejdak

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Because some electronics don’t like to play outside their range. Don’t know that either would limit you to 14v as a form of self protection for the pack. I suspect using a 12v pack and a good battery to get to 24v would not work either, but might be a way to check,


take a battery out of a vehicle,, take it and pack to truck, and hope the magic smoke stays inside everything.
Don't like the idea of watching for "magic smoke". But this would be an interesting experiment too.
Thanks
 

WildBill

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I agree with you on the lead acid batter jump packs. probably act similar to two batteries is series . I know these Lithium packs have power switches on them. Turning one on at a time, probably won't work nor switching to switch them both on at the same time.
I've contacted NOCO and waiting for an answer from them.
Interesting that you had two packs there to try. Thanks for the experiment.
I have a bunch of them, super handy. The have cig lighter adapter cables and laptop charging adapters so I power all kinds of stuff off them. You can even get them with a 120v jack built in now. No problem on testing it. Was curious as well.
 

joecon

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The small lithium packs will not work but the old ones with batteries in them will. If you are jumping a 24-volt vehicle it will most likely have two 12-volt batteries, just hook a pack to each battery.
 

Old Man Roger

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I just tried it with two of my lithium jump packs, they have a little protection box inline on the cables that gets unhappy and won't let power through. I bet regular lead acid battery jump packs would work fine though, or if you bypassed the protection boxes on the cables. Youi can also buy the cable assemblies without the protection on amazon for cheap.
The lipo type might be protected against the exact thing he’s trying to do, because the separate packs wouldn’t be balanced. Hooking two lipo packs that aren’t charged to the same voltage could cause a fire. That’s not usually a problem with a regular automotive battery.
 

AA/FC

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I can't speak for any other brands, or lithium jump packs.... But the JNC660 is a 12 volt starter. JNC also makes a 12/24 volt starter. If you look inside the 12/24 unit, it has 2 of the exact same batteries as the JNC600 12 volt pack. For 12 volts, it uses both batteries in parallel, for 24 volt it uses both batteries in series. The JNC660 12 volt pack has no internal switching or circuitry.... The jumper leads are connected straight to the battery. You can absolutely use two JNC600 packs in series to get 24 volts. I am ONLY talking about the JNC660 jump packs. If talking about any other 12 volt starters then you're on your own.
 
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whejdak

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I can't speak for any other brands, or lithium jump packs.... But the JNC660 is a 12 volt starter. JNC also makes a 12/24 volt starter. If you look inside the 12/24 unit, it has 2 of the exact same batteries as the JNC600 12 volt pack. For 12 volts, it uses both batteries in parallel, for 24 volt it uses both batteries in series. The JNC660 12 volt pack has no internal switching or circuitry.... The jumper leads are connected straight to the battery. You can absolutely use two JNC600 packs in series to get 24 volts. I am ONLY talking about the JNC660 jump packs. If talking about any other 12 volt starters then you're on your own.
Wow, now that is getting right down to the science of it. I kind of thought that it might be that way, but wasn't going to purchase just so I could take it apart. I'm still waiting on NOCO for an answer and will post if they respond.
 
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whejdak

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Wow, now that is getting right down to the science of it. I kind of thought that it might be that way, but wasn't going to purchase just so I could take it apart. I'm still waiting on NOCO for an answer and will post if they respond.
I take it that you have the 12/24 JNC Pack. I understand that the series connection will give the 24 volts. But, how does the unit get switched back and forth from 12 to 24? Is there an external switch?
 

cgrutt

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I can't speak for any other brands, or lithium jump packs.... But the JNC660 is a 12 volt starter. JNC also makes a 12/24 volt starter. If you look inside the 12/24 unit, it has 2 of the exact same batteries as the JNC600 12 volt pack. For 12 volts, it uses both batteries in parallel, for 24 volt it uses both batteries in series. The JNC660 12 volt pack has no internal switching or circuitry.... The jumper leads are connected straight to the battery. You can absolutely use two JNC600 packs in series to get 24 volts. I am ONLY talking about the JNC660 jump packs. If talking about any other 12 volt starters then you're on your own.
My DSR is the same way... two identical batteries connected directly (through a fusable link) in parallel to the terminals. I just changed the batteries last week. I believe they make a version that is 12/24 as well but am quite certain you would be able to run two packs in series for 24V if needed. The electronics were just for charging and also were connected directly to batteries.

OP, keep in mind though there is no voltage regulator or other protection on these and the 12V is just nominal voltage the batteries generally run around 14V fully charged so two in series may generate 28V or higher.

20240131_155418.jpg
 
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whejdak

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Great picture and thanks. So all these jump packs are is a battery in a case with a charger built in. Would be like carrying your car battery around with a case on it.
 

cgrutt

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Great picture and thanks. So all these jump packs are is a battery in a case with a charger built in. Would be like carrying your car battery around with a case on it.
Yeah pretty much at least for the SLA-type packs. I believe most only have one battery though. Only complaint with mine is its very heavy but it works great.
 
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whejdak

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Amazon says $489.30 for the Autogen-Star jump pack. this is why I'm looking for two 12's and hooking in series . A lot less money for a made up 24 volt pack . In addition, I would have two 12's available not one unit. I could store in two different places, and when I needed 24 I'd just series the two. Still waiting for NOCO to respond.
 
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whejdak

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I had an old jump pack that I was going to throw away. Now that I see what is inside, I'm going to take this one apart. Maybe just buy batteries for the inside and i'll have an sort of new one to use.
That picture really helped. It looks like manufacture potted the hole where the screws hold it together.
 

AA/FC

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I take it that you have the 12/24 JNC Pack. I understand that the series connection will give the 24 volts. But, how does the unit get switched back and forth from 12 to 24? Is there an external switch?
No, I do not own a 12/24 JNC jump pack.... But I have a friend who does and he told me the pack uses the exact same batteries as the JNC 660, which I do own three of. There are two Anderson style connectors on the back of the 12/24pack, one connector is 12 volts, the other connector is 24 volts. You simply plug your cable set into whatever connector has the voltage you're looking for. See picture below.

1224.jpg
 

PelicanPines

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Amazon says $489.30 for the Autogen-Star jump pack. this is why I'm looking for two 12's and hooking in series . A lot less money for a made up 24 volt pack . In addition, I would have two 12's available not one unit. I could store in two different places, and when I needed 24 I'd just series the two. Still waiting for NOCO to respond.
Please let us know what NOCO says.. they are the jump pack/charger of my choice.
 
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whejdak

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No, I do not own a 12/24 JNC jump pack.... But I have a friend who does and he told me the pack uses the exact same batteries as the JNC 660, which I do own three of. There are two Anderson style connectors on the back of the 12/24pack, one connector is 12 volts, the other connector is 24 volts. You simply plug your cable set into whatever connector has the voltage you're looking for. See picture below.

1224.jpg
 
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whejdak

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Got it. So that's how they mechanically create separation. I kept looking for some sort of switch and couldn't find it.
Thanks again.
 
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whejdak

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OK. Got my calculator out here and now and figured it out.

one JNC1224 $411.00
or two JNC660 for $271.00

Using two 660 units in series I got my 24 volt jump pack.

in addition, I have the flexibility to use each pack in different locations.

If the 24 goes out I am screwed. If one of the l2 units goes out i still have a spare 12 volt jump pack just couldn't use 24.

Genius
 
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whejdak

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As promised, here is the post from NOCO on my question about connecting two 12 NOCO's to make one 24 Volt unit.
I think the answer is no.
the last sentence seems to state that.
Although it isn't a direct answer to my question, I think he is saying don't do it.
Bill



Thanks for contacting NOCO Support.
For vehicles with dual battery configurations, you would connect both the positive and negative clamps of the BOOST device to the battery closest to the starter.
If your batteries are in parallel, you can use 2 BOOSTs to double the starting power if needed.
If your batteries are in series, you cannot use 2 12V BOOSTs. A 24V jump starter would be required.
Regards,
Chris G
NOCO Customer Support Supervisor
 

Vercingetorix

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I don’t see why using 2 Nocos in series would not provide 24v if you were to bypass the safeties and use Manual Overide. Doesn’t sound safe though.
IMG_6344.jpeg
 

johninct

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I hooked my JNC jumper pack in series with a car battery and easily started my Cat 215 excavator.
 
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whejdak

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This confirms to me that all (probably) Lead Acid Battery Packs can do what I want it to do. Not Ni-Cad. Only lead acid.
I'll soon find out for sure. I purchased my first Pack and I'll be getting my second one shortly. Going to hook up just like the above picture for 24 volts.
 

jd_1138

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Funny story about an experience I had last week. We were pulling into a local store, and an older man and woman were in front of a car with the hood up. With winter, a lot of batteries have been failing. It was about a ten-year-old Kia.

I pulled up and lowered my window. The old man kept rambling on, but the lady turned to me. I quickly asked if they needed a jump box, as I had one. At that point, the man turned and proceeded to give me a bitter-filled rant about how he retired from the Air Force as a technician on helicopters and airplanes then was a master tech for 20 years at a local transit authority, and he pointed 100 feet over to where a nearly new looking Nissan Titan truck was parked. He began enumerating the tools he had inside -- jump box, cables, jack, 300-piece tool set, air compressor, etc..

His tone was kinda in between Dirty Harry and John Wayne talking at bad dudes. Bitter and angry sounding. "So no mister we don't need your help! Run along as you're wasting my time", he said. She was mortified and apologized.

I started to reply to him that if he's in such a hurry a simple "we're good" even without saying "thanks anyway" would've sufficed, but with how s--t communication/manners are these days, he quickly turned his head back to the car/her as soon as "time" came out of his lips.

a-hole............no wonder a lot of people aren't good samaritans anymore
 
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pl_silverado

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Probably not much use to, OP, but there is a company, in Britain, that does exactly, what he is looking forScreenshot_20240215-202223.png

These used to be sold by Snap-on under part number EECS309B. Only thing made in Britain was the container, the battery was foreign IIRC. I have 2 laying in the scrap pile. I replaced both of mine with 2 JNC770's.
 
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