Series/parallel for jump start

[8922659]

Thinking on service truck with 4 batteries. I thinking I could hook up series parallel for 24 volt jump on a 12volt service truck . Any thoughts ?

 

[lantraxco]

Yep! Just want to connect your truck up to only one set of the 12V so it never gets 24

 

[Midnightmoon]

I set up two batteries separate from the truck batteries with a golf cart solenoid to allow for 12 or 24 volt jump starts along with a quick connect jumper cable setup. The truck while running charged them.

 

[Midnightmoon]

It's been a while since I had this setup I used a series parralel switch. I cant wrap my head around how you could make it work without a switch and maintain the batteries equally. 24volt jumper in place of starter

 

[Old Doug]

If i had a very new truck i would not do this. If i was needing to do this alot i would get 2 spare bats to haul around if you hauled a welder or had a coverter to charge them.

 

[Midnightmoon]

They ran series parralel switches on trucks with 24 volt starters for a long time. If switch goes bad you just dont have 24volt output. The switch is the only way I would do it

 

[1466IH]

Another vote for the series parallel switch. I have this one but been waiting on some free time to get it installed.
http://www.texasindustrialelectric.com/relays_1119845.asp

 

[funwithfuel]

That looks exactly like what Kenworth used to use on their old 24/12 systems. I believe I've seen it an an old IH loadstar or transtar with a super 290 as well. That old girl still had the compression relief under the dash.

 

[Tugger2]

My electrical repair guy knows these S/P switches well but says its hard to get parts to repair them.

 

[lantraxco]

My electrical repair guy knows these S/P switches well but says its hard to get parts to repair them.

They're a hundred bucks, and with what little use one would get in a setup like this, keep it dry it will probably outlive you.

 

[Midnightmoon]

I used one for over 5 years in frigid temps all the time jumping loaders for snow removal it never failed me. 100 bucks is well worth it.

 

[8922659]

What I ended up doing is just add 2 batteries 1000 amp each in steal box wired in series / parallel switch just like 70s Kenworth so battery’s charge off truck alt quick connector for jump start cables so I can use same cables for 12 volt off truck batteries a switch in box panel to control s/p switch .