48V, 50A+ battery charger?

twistedtree
twistedtree Solar Expert Posts: 135 ✭✭✭
Can anyone recommend a 48V battery charger that can produce 50-100A output? I'm considering adding a second charger in parallel with my off-grid inverter/charger to get a higher bulk charge current when running my generator. My Inverter/charger puts out 100A, and I'd like to get another 50+ amps. 240V AC input is fine, and I'd hard wire the whole thing in place.

Thanks

Comments

  • XRinger
    XRinger Solar Expert Posts: 529 ✭✭✭
    Re: 48V, 50A+ battery charger?

    I was looking at a way to quick-charge my small 48v bank the other day,
    (in case of no sun) and saw some in the $500 range.
    http://www.chargingchargers.com/quick-charge/qp.html

    50-100 amps at 48v seems pretty high (to me anyway).
    2.5 to 5.2kW. You must be running a pretty good generator.

    My gas generator is only 5kW, so I would likely shoot for a slower charge,
    and a less expensive charger.
    Plus, at loads over 2.4 kW, my generator uses a lot more fuel..
    And the sun is going to come out eventually.. I hope! 8)

    Happy Holidays,
    Rich
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: 48V, 50A+ battery charger?

    I will toss out one inexpensive solution that I've found.

    At an electronic recycler, did find a Transformer/Rectifier/Capacitor power supply. It puts out about 60 VDC or so at 50 Amps. It was for electroplating, very well built and I bought it for something like $ 75.. However, it had no regulator, so I've used it with a generator plus an MX-60 as the charge controller. Realize that the MX makes it about a $600. solution, but for this application, it is used when there is very little PV input.

    These kinds of supplies show at recyclers these days, as they are considered Toxic Waste (which, I duess they are).

    Also, others, like member ' greenerpower ' have reported using large switching DC supplies surplused from telecom etc as a source of inexpensive LARGE DC power supplies. It might be worth poking around on the net, especially if you are a bit handy. Hope you find a solution. There IS a large hole in the Charger market for this large charger. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: 48V, 50A+ battery charger?

    What have you got for an inverter? Usually a good brand 48 Volt inverter will have a built-in 50 Amp (or so) charger.

    Examples:
    Magnum http://www.solar-electric.com/maenms4444wa.html
    Outback http://www.solar-electric.com/vfx3648.html
    Xantrex http://www.solar-electric.com/xaxw12hyin.html
  • twistedtree
    twistedtree Solar Expert Posts: 135 ✭✭✭
    Re: 48V, 50A+ battery charger?

    My inverter is a Xantrex XW6048 and it produces 100A. But the advice I'm getting is that I really should have 150A or so, hence the desire to come up with another 50A. I could throw in another inverter, but that's a pretty expensive route, especially after all the breakers, conduit boxes, cables, etc.. And then I'd have another inverter running all the time wasting power.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: 48V, 50A+ battery charger?

    I'll answer for the OP, from other threads here, he has an XW 6048 IIRC. It is rated at 100 Amps DC charge. It came up in this thread:
    http://forum.solar-electric.com/showthread.php?t=10026

    Here is a link to a link from a similar discussion scroll to post #5, and click on "this old thread":
    http://forum.solar-electric.com/showthread.php?p=63664#post63664

    (Sorry for the link-to-link, but it was greenerpower's original info, and did not wanna steal his thunder)

    There really is a need for large DC chargers independant of inverters IMHO.

    EDIT: I'm a slow typer, the OP answered it.

    HH Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: 48V, 50A+ battery charger?
    My inverter is a Xantrex XW6048 and it produces 100A. But the advice I'm getting is that I really should have 150A or so, hence the desire to come up with another 50A. I could throw in another inverter, but that's a pretty expensive route, especially after all the breakers, conduit boxes, cables, etc.. And then I'd have another inverter running all the time wasting power.

    100 Amps can handle a 1000 Amp hour battery bank. It could handle as much as 2000 Amp hours @ 5%. For your proposed 1473 Amp hour bank it would be 6.7% peak current. So were back to the question of do you really need that much battery? Right now you've got up to 367 Amps hours (735 @ 50% DOD) and that's about 17,640 Watt hours. I think you were looking for18 kW hours.

    If I'm completely out to lunch here, sorry; I'm answering about 15 questions a day and am probably getting terribly confused. :blush:
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: 48V, 50A+ battery charger?

    Marc,

    Couple of things. This existing bank is considered to be 1350 AH @ the 20 Hr rate, but due to specmanship, Surrette (and most other mfgs) spec the capacity with 1.280 SG electrolyte, but usually ship the batteries with 1.265 electrolyte. 1.265 yields a 5% reduction in the capacity, so this bank is really smaller, just like you were counciling -- about 1283 AH,

    As I've read it, this bank is two-sih years old, and should have a long life, twisted tree is just trying to tune the charge/EQ parameters of resolve some capacity issues etc.

    And BTW, at 1283 AH, the Surrette recommended Return Amps for end of Asorb of 1-2 % of 20 Hr capacity is slightly reduced to 13 to 25 Amps, this would slightly increase Asorb time, and battery charge.

    twistedtree can speak for himself, just wanted to post this further rumination.

    Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: 48V, 50A+ battery charger?

    There are a few 48V chargers available used for forklift batteries. Try an ebay search for "forklift charger"
  • twistedtree
    twistedtree Solar Expert Posts: 135 ✭✭✭
    Re: 48V, 50A+ battery charger?

    Vic, thanks for helping fill in the blanks. To read the whole story, check this thread http://forum.solar-electric.com/showthread.php?t=10026

    Since no simple solution has emerged, I'm going to sit tight with what I have. If I decide to expand, I'll probably add a second XW6048 so I get extra inverter as well as charger, and so they play well together charging.
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: 48V, 50A+ battery charger?

    You're going to have a hard time finding a 50A 48 volt charger in anything other than a hard-wired format because most of the standalone chargers have NEMA 5-15 plugs -- standard 15A 120VAC -- that are rated for 15 amps continuous. 15 amps @ 120 volts is a few amps shy of anything that will make 50 amps DC output.

    That said, there's no reason you can't parallel a pair of Iota chargers. This would probably be a better solution as you'd get to balance both legs of a 120/240 volt generator. Dollar for dollar, that's how I'd roll.
  • twistedtree
    twistedtree Solar Expert Posts: 135 ✭✭✭
    Re: 48V, 50A+ battery charger?

    Thanks. I'd be happy with 240V hard wired. As you point out, there's no other way to get 2500W, and it's a more balanced load in the generator.
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: 48V, 50A+ battery charger?
    Thanks. I'd be happy with 240V hard wired. As you point out, there's no other way to get 2500W, and it's a more balanced load in the generator.

    Well ... if you want hardwired, get a 4x4 box, feed it with the conductors from the generator, install a pair of NEMA 5-20 duplex receptacles, then plug in the pair of Iotas, one per phase leg. The Iotas have terminal blocks for their outputs. Take those into a small box with the appropriate DC circuit breakers, then off to the battery buss.

    Voila!
  • twistedtree
    twistedtree Solar Expert Posts: 135 ✭✭✭
    Re: 48V, 50A+ battery charger?

    It looks like the Iota 48V charger is only 13A output, and goes for about $325 each. I'd need four yielding 52A (assuming they parallel properly and still put out full current), plus breakers, wire, conduit, etc. Probably $1500 by the time all is said and done.

    Right now I plan to do nothing. I'm replacing the bad cell that I have, and will just keep going with my current 100A max charge rate.

    Plan B is to add a second XW6048. It's 2x+ the cost of a bank of Iotas, but 2x the output (100A) and also gives addition inverter power as a bonus. I just checked my power panel and it will fit OK.
  • twistedtree
    twistedtree Solar Expert Posts: 135 ✭✭✭
    It's now 4 years later and guess what? I'm replacing another bad cell in the Surrette battery bank. Interestingly, it's the same cell as last time. The replacement always ran really hot at 1300 SG or higher. I spoke with Surrette about it when I first deployed the replacement cell and they insisted it was fine and would "settle in". Not. Hopefully I'll have better luck with this 2nd replacement.