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Added Dual Batteries. Regulator Needed?

Discussion in 'Commercial Snow Removal' started by green frog, Mar 3, 2009.

  1. green frog

    green frog Senior Member
    Messages: 246

    I just added a second battery to my 1995 f250, but I havent had s chance to plow with it yet. So do I need to put a regulator in ? I have heard yes and no. Please tell me and why I should go that way.
  2. Blazin

    Blazin Senior Member
    Messages: 185

    I run dual batteries in my 86 K 30. No regulator.
  3. Rc2505

    Rc2505 PlowSite.com Addict
    Messages: 1,245

    I run duals, and don't have a regulator in any of my trucks.
  4. Dustball

    Dustball Senior Member
    Messages: 274

    I think you meant battery isolator when you said regulator.

    You'll need an isolator if you plan on using the batteries separately in situations where you want to use one battery for use with the engine off (radio, camper lights, etc) and still have the reserve capacity of the second battery to start and run the engine when the first one is drawn down.

    RODHALL Senior Member
    Messages: 374

    you should run a battery isolator when you have dual batteries to get the most out of both.

    what happens is if you just strait wire a second batt in, the second batt in line can overcharge and explode or catch fire, under charge and be useless. This can also make alts wear out quickly.
  6. sparky8370

    sparky8370 Senior Member
    Messages: 234

    Could you explain that one to me. If you wire two batts, they are in parallel. This keeps the same voltage but doubles the ampacity. If one gets overharged than both will. Unless they are different rated batteries.
  7. Lowell_Ma_Snow

    Lowell_Ma_Snow Member
    Messages: 60

    Watching this thread. I just posted why the two batteries........duh.
  8. B&B

    B&B PlowSite Fanatic
    Messages: 12,777

    Use the search with the keywords "Dual Batteries" .It's been covered no less than a million times here so be sure to take a bathroom break before you start through the past threads. :D
    Last edited: Mar 4, 2009
  9. ServiceOnSite

    ServiceOnSite Senior Member
    Messages: 950

    lol kinda a dead horse around here. But if you do search it out you will find many answers. what you do with the info is up to you.

    RODHALL Senior Member
    Messages: 374

    NO it don't......
    the voltage regulator is only checking one of the batts. so when it puts out amps it is doing so to charge ONE batt. in parallel it has no idea what the second needs.

    So when you fist batt needs 60 amps and alt puts out 60 amps your first batt only sees 30amps. second also sees 30 amps (needed or not) i have never see two batts always need chagred at same rate.... so either going to over charge or under charge on of them.
  11. festerw

    festerw Senior Member
    Messages: 986

    The regulator checks the charging system in whole, it doesn't care if there is one battery or 4. Either way adding an isolator will not solve the problem you're talking about anyway.
  12. sparky8370

    sparky8370 Senior Member
    Messages: 234

    If they are in parallel, they will equalize. If one needs juice, than the other does two unless there is a problem. Unless you know of a situation where two good and identical batteries, that are connected to each other, will charge or drain at different rates. I would like an example if you could please.
  13. got-h2o

    got-h2o 2000 Club Member
    Messages: 2,440

    I'm with sparky
  14. cretebaby

    cretebaby PlowSite Veteran
    Messages: 4,162

    Got to figure someone named Sparky knows his electricity:D:jester:
  15. Dustball

    Dustball Senior Member
    Messages: 274

    Unless you're isolating the two batteries, you're not going to get different readings from the two batteries.

    It's just like the plumbing system in your house- the pressure is the same no matter where you're checking it.
  16. rollin snow

    rollin snow Junior Member
    Messages: 18

    no just hook + 2 + and neg- 2 neg no pluming this truck not your house. the batt. will work together same volts .
  17. justme-

    justme- 2000 Club Member
    Messages: 2,138

    MAKE sure you have the same rating batteries tho- you WILL cause problems in the regulator, possibly the computer, and definitely in the battery life if they do not match.
    You need the same capacity batteries regardless of the isolator (which is useless in a plow truck)
    If you have 1 800CCA and 1 600CCA they will charge at different rates, the 800 will never be fully charged while the 600 will overcharge because they try to even themselves out as was said. The problem is the regulator sees a situation where the battery is calling for power and can fry, or the smaller battery can fry (explode, leak, boil out, etc). Newer trucks with the regulator in the computer, well, that gets expensive.

    Ideally you should have 2 identical batteries in age, size, capacity and brand installed at the same time.
    Yeah, there it more written in the forums about dual batteries than anything else!
  18. theplowmeister

    theplowmeister 2000 Club Member
    from MA
    Messages: 2,617

    Man there is a LOT of BAD info on this site. the regulator regulates the VOLTAGE!!! a battery will take what a battery will take. the problem is not charging (unless you have a bad battery then all bets are off) you cant over charge one battery (unless its bad) the regulator regulates the voltage from 13 to 14.5 V it dont care if there are 1 or 10 batteries.
  19. justme-

    justme- 2000 Club Member
    Messages: 2,138

    Yes there is, and that wasn't some of it. You and I have had this argument before in other dual batt threads.... you can overcharge a battery and when a regulator goes bad you will often overcharge a battery and often damage the alt. Yes, the regulator regulates voltage- how do you think the charging system works? Voltage is used to monitor the battery and switch the fields on/off in the alt to regulate the amount of power produced. A battery at 12.3 volts need more current supplied to charge it than a battery at 13.5 volts.
  20. theplowmeister

    theplowmeister 2000 Club Member
    from MA
    Messages: 2,617

    You are right you should have the same size, type, brand, age of batteries.

    You are wrong that different batteries will cause a charging problem.
    This is the INTERNET and I cant prove it, even with spending way more time than I willing to spend.

    When you are not charging that is when you run into problems! one battery will discharge through the other. and thereby damage a battery.

    Batteries have internal resistance (that is what limits the maximum current that a battery can supply). if one battery has a slightly lower internal resistance the other battery will discharge through it and damage one or both. That is why you should use two identical batteries that you buy new at the same time.
    Last edited: Mar 8, 2009