charging a 12v bank with generator

nyarelathodep
nyarelathodep Solar Expert Posts: 99 ✭✭
Looking for recommendations on a decent and economical choice for a charger when charging a couple of GCs in a 12v bank with a generator. I'm to understand desulfating is a key feature, but the number of choices in chargers seems endless.

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging a 12v bank with generator

    Desulphating is not a key feature. It is a sales gimmick. Rather than trying to fix a problem after it occurs (desulphating) prevent it in the first place by keeping the batteries charged.

    There are in fact no ideal stand-alone battery chargers for RE systems. Those built in to inverters are the best you can get, but outside of that you're stuck with things that are 'modified' for use such as the Iota models which are re-purposed RV converter design.

    With two GC2's you have roughly 220 Amp hours so you need a charger capable of around 20 Amps of current. That would be important because no one wants to run their generator any longer than necessary, what with fuel being so expensive. Get it through Bulk as quickly as possible without cooking them.

    Here's the Iota: http://www.solar-electric.com/batteries-meters-accessories/bach2/bach1/dls-30.html
  • Alaska Man
    Alaska Man Solar Expert Posts: 252 ✭✭
    Re: charging a 12v bank with generator

    The generator needs to put out good power. I bought a big 6 KW diesel generator off Craig's List that my charger would not work with. I adjusted the Hertz, (from 55-60) but the variation in the cycle produced by the genny gave the charger fits. The Hertz produced would drift. Older generators don't always work with new fancy chargers if the power cycle varies.

    So I went out and bought a new EFI 3000 Yamaha. I love that thing, quiet, efficient, easy to move around and it has a key start. (I hate yanking on ropes.) My charger loves that genny as much as I do.

    It also comes with a remote start, but don't waste your money. You have to disengage the choke to hook it up. (Not a very good design)
  • nyarelathodep
    nyarelathodep Solar Expert Posts: 99 ✭✭
    Re: charging a 12v bank with generator

    Once again, mr Coot, you are the man. Would that mean that 4 batteries comprising a 12v bank want 40 amps of current then? And does the size of the generator have any bearing on the equation aside from fuel efficiency? The two options are a Honda 2000 (not the inverter kind) and a Briggs 5550.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: charging a 12v bank with generator
    Once again, mr Coot, you are the man. Would that mean that 4 batteries comprising a 12v bank want 40 amps of current then? And does the size of the generator have any bearing on the equation aside from fuel efficiency? The two options are a Honda 2000 (not the inverter kind) and a Briggs 5550.

    Yes: with generator charging definitely go for the 10% current rule-of-thumb or even more (so long as it doesn't exceed the limit the batteries can take, which will vary by battery).

    And yes the generator needs to be able to supply the power required, including the in-rush current which some chargers (such as the Iota, regrettably) have a pretty high in-rush. So in simple turns 30 Amps @ 12 Volts is 360 Watts which is pretty easy to come up with but once the power factor of the charger is considered (some better than others) as well as in-rush ... you can end up needing more generator capacity than would seem necessary at first glance.

    The 30 Amp 120 VAC in-rush of the Iotas have confounded some users as that's 3600 Volt Amps they weren't expecting to have to supply. There's some tricks to get around it, but nothing is simpler than a gen capable of the power. "Standard" generators (aka fixed RPM type) usually have better surge handling than inverter-gens, but as Alaska Man found out they aren't as frequency stable and can cause problems with "smart" chargers.

    The better inverter-chargers do not have this trouble and can be used with quite minimal-sized gens.

    It's just never easy, is it?
  • nyarelathodep
    nyarelathodep Solar Expert Posts: 99 ✭✭
    Re: charging a 12v bank with generator

    Heh, your last statement was exactly what i was thinking woke trading through the details. It might just be more worthwhile to search for a decent lower wattage psw inverter/charger than try to use the suresine and stand alone charger, as was the plan. I noticed those yamaha ef2000is ones (which I'd like to get anyway) have a charger built into them... is that an applicable feature for such a use with RE type batteries? That could be the simpler solution right there perhaps. I'm guessing it's not going to be quite that easy though.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: charging a 12v bank with generator
    I noticed those yamaha ef2000is ones (which I'd like to get anyway) have a charger built into them... is that an applicable feature for such a use with RE type batteries? That could be the simpler solution right there perhaps. I'm guessing it's not going to be quite that easy though.

    Correct. It's not that easy:cry: There is very limited power available from that "charger", and no proper 3 stage charging.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: charging a 12v bank with generator

    As my "backup" and utility charger, I have a VEC1093 12V Charger (40 amps) (amazon) ($100) that works pretty good for 12V stuff. It's an inverter type powersupply, and it does a nice slow ramp up to full power, as it tests and charges. Only good Power Factor .7, not corrected (but newer models may have PF correction)Has some smarts inside to tell if a battery is just not going to charge, and will go offline after a couple hours. Or it will charge a good battery all day till it's full, then shut off. Has a couple settings for Flooded, Sealed.... may work ok with AGM, but I don't know if it will top off a true deep cycle 400ah cell.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: charging a 12v bank with generator

    I make a little different computation when I size a battery charger for a Battery bank charged off grid Generator the way I use them. I assume that the charger will be used to replace amp hrs from the 50% to the 85% range or what does it take to replace the average use over time that the generator will be used. If you consider the charger to be 95% efficient a 30 amp charger will average 28 amps per hour of run time on ECO idle. Looking at a 10 hour run time thats 280 amp hrs +/-, it's either replenishing the bank with no load or powering the loads and replenishing the Bank. Sometimes I will set the up with two chargers, say a 30 Amp and a 45 amp. I'll put the 45 amp on a relay and only pull it in when a certain load is present, most cases it's a 5000 btu A/C that pulls 60-70 amps @ 12 v. This way I zero the A/C use and charge the bank on the off cycle. This way you can absorb with the PV and still have all the power you need.

    The Honda EU2000 will power most 75 amp chargers, as will the Yamaha 2000IS. A 30 amp charger will just barely pull them out of the low idle on the ECO throttle. The Honda is a little bit quieter, The Yamaha wins the fuel consumption, it'll run 11 hours on a gallon of gas, the Honda will run 8-9 on a gallon. The Honda has a fuel pump and will run on a auxiliary fuel tank , the Yamaha won't, it has no fuel pump. If it was just fuel, I'd choose the Yamaha, but your talking about a cup or two over 10 hrs or so.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator

    I'm a real fan of the Honda EU2000i because it effortlessly powers Xantrex 60 amp chargers, from idling in Eco mode without a hiccup. (That part part is important to me) The Yamaha may be every bit as good, or better - but I only own the Honda's because that's what I started with.

    Different application than most, but I went this way for a mobile setup to get very fast bulk charging for a 100 ah battery that sees very high equipments loads for a short durations.

    Change the oil and keep them clean, and watch them run for a whole lot of years.....
    I always have more questions than answers. That's the nature of life.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: charging a 12v bank with generator

    Marc,

    I guess it is this one?

    http://www.xantrex.com/power-products/battery-chargers/truecharge-2-2.aspx

    Xantrex Battery Chargers TRUECharge2 (20A, 40A, & 60A) - New Generation (24 volt @ 30 amp maximum available too):
    20, 40, & 60 Amp - 90-265 Vac / 47-63 Hz
    AMP UP-TO 120A GLOBALLY!
    Now with PARALLEL STACKING FEATURE*

    This NEW feature allows two chargers to work together to combine the output current, achieving up to 120A for large battery banks.
    *Applies to the new generation TRUECharge2 models - 20A (part #804-1220-02), 40A (part #804-1240-02) & 60A (part #804-1260-02). Please ensure you order TRUECharge2 Remote Panel part #808-8040-01 for parallel stacking.
    "Every RVer who has ever experienced less-than-stellar performances from the stock converter/charger should seriously consider adding the TRUECharge2 to the 12-volt DC battery systems", says Gary Bunzer of RV Doctor. Click here to read his product review.

    • Description
    • Features
    • Accessories
    • Videos

    Performance Features
    • 12V models available in 20A, 40A and 60A
    • Microprocessor-controlled, multistage charging algorithms
    • Settings for two and three-stage charging
    • Settings for flooded, gel, AGM or lead-calcium batteries
    • Auto-ranging universal input voltage (90-265 Vac, 47-63 Hz) is also compatible with a generator or other low-quality power sources
    • Temperature-compensated charging
    • Power factor corrected for efficient charging
    • Battery-equalization feature
    • Ability to charge ‘dead’ batteries
    • Battery temperature sensor available (Part #808-0232-01)
    • Optional remote panel (#808-8040-01) required for parallel stacking
    Protection Features
    • Reverse battery polarity protection
    • Drip-proof design
    • Over and under-temperature protection
    • DC over-voltage protection
    • Battery overcharging protection
    They had great specifications, and the older generation had good reviews (version 1).

    The 2nd gen have been sort of missing in action (not shipping, slipping from original dates?).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator

    Yes, Sir - those are the units (60 amp) that I bought. I bought the first one in March of last year to test and ended up getting four more about this time last year. I supplied the kits to my customer who uses them out in the field for the oil and gas industry. I kept one of the chargers for use in my own shop, because I like it!

    I chose the Honda for my customers application, because that's what I've personally for years - so I was comfortable with them.

    Marc
    I always have more questions than answers. That's the nature of life.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: charging a 12v bank with generator

    They are a great charger, but not a lot of bang for your buck ( $400 + ) . The other issue I had with them if you buy the the $80 remote you find that the output is only adjustable in 20% increments and the same old Xantrex charging Algorithms , so it kind of limits the way you can use it. The warranty service on them is not real swift since the service centers will not touch them and they have to be sent to Elkhart and you end up with $50 in shipping.

    Be wary of " Smart" chargers anytime you plan to charge and run a load on the bank your charging, they can get confused and fault. You can end up with a expensive brick.

    .
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator

    I can clearly understand that they may not meet everyone's needs, but I paid $325. each, I don't need the remote and the standard AGM charge profile is fine for the batteries that I deal with. They spend a lot of time at full output and keep ticking, even at 100 F ambient. Of course I may be here complaining bitterly when one dies, but so far, so good ;)

    I am going to buy one of these to try out: http://www.kisaetechnology.com/products_ac_ac1260.php because I can buy them for for a lot less than I paid for the Xantrex units. I want to see how it reacts to hard use.

    Marc
    I always have more questions than answers. That's the nature of life.
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator
    They are a great charger, but not a lot of bang for your buck ( $400 + ) . The other issue I had with them if you buy the the $80 remote you find that the output is only adjustable in 20% increments and the same old Xantrex charging Algorithms , so it kind of limits the way you can use it. The warranty service on them is not real swift since the service centers will not touch them and they have to be sent to Elkhart and you end up with $50 in shipping.

    Be wary of " Smart" chargers anytime you plan to charge and run a load on the bank your charging, they can get confused and fault. You can end up with a expensive brick.

    .

    Interesting observation and good info to have! Which charger have you seen do this? I'm guessing Samlex?

    In my application above, the Xantrex battery/charger combo gets hit with a 120-230 amp load and the the charger stays online. When the load goes away, the charging continues. This pattern repeats over and over. Typically, the 100 ah battery is at 11.7v to 12.0v at the end of a typical operation cycle, so the charger only needs to run 3-4.5 hours on the generator to finish the absorption for the next cycle.

    Because I'm looking at other chargers, I'd sure like to know which one(s) have a problem along these lines! What have you seen?

    Marc
    I always have more questions than answers. That's the nature of life.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: charging a 12v bank with generator
    Marc Kurth wrote: »
    Because I'm looking at other chargers

    Have you looked here? They have a line of power factor corrected chargers.
    http://sterling-power-usa.com/

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator

    No, I had not - but I certainly appreciate new sources!

    I'm left wondering about Blackcherry04's trouble experience with his smart charger that didn't handle loads while charging. Might be best to stick with what I already know works well.

    Marc
    I always have more questions than answers. That's the nature of life.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: charging a 12v bank with generator
    Marc Kurth wrote: »

    Because I'm looking at other chargers, I'd sure like to know which one(s) have a problem along these lines! What have you seen?

    Marc
    The Meanwell PB-1000 faulted over and over anytime the bank was loaded. So for me it ended up as a $359 door stop.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: charging a 12v bank with generator
    Be wary of " Smart" chargers anytime you plan to charge and run a load on the bank your charging, they can get confused and fault. You can end up with a expensive brick.
    Marc Kurth wrote: »
    Because I'm looking at other chargers, I'd sure like to know which one(s) have a problem along these lines! What have you seen?

    In just 5 minutes I searched and found a half dozen chargers that are "too intelligent" to work in an RE system. There are two sorts of problems that crop up: 1) any charger that uses a constant current stage in its charging protocol will get confused and fault out if there are loads or other chargers hooked up to the battery. 2) many chargers have built in diagnostics as part of their charging protocol. For example here is a diagram from a NOCO battery charger... I think that 'soft start' charge is partly diagnostic, it looks to see how the battery responds to a soft charge before it begins the hard charge.
    Attachment not found.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Marc Kurth
    Marc Kurth Solar Expert Posts: 1,142 ✭✭✭✭
    Re: charging a 12v bank with generator

    Looks I'll stick with the 60 amp Xantrex chargers I'm using. No problem at all hitting it with large/small loads during bulk, absorb or float. It just keeps doing what I would expect it to.
    Probably a difference in time. I was hitting it with light and very heavy loads for a few seconds up to about 80 minutes. I applied 50 and 150 loads on both 80 ah and 400 ah batteries, I figured that if I was going to see a problem, it would be on the small battery with the big load.

    Again, the difference may be time - I did not let it sit under load while charging for several hours....... could be the difference between failure and not. I do appreciate the info.

    Marc
    I always have more questions than answers. That's the nature of life.