AC to DC battery charger questions

notsobrightnotsobright Solar Expert Posts: 247 ✭✭
Im just about ready to get a generator for use in charging my batteries when the PV cant keep up with demands. Ive decided on the Honda EU2000i.

its rated at 1600w continous, 2000 max so whats the higest amp 12 volt chargers I could run on the Honda 2000i continously if needed? Im having trouble determining the max current draw on most of the chargers Ive been looking at.

also, Id like to learn what the top brands available are. from reading here it seems IOTA is the way to go and that is the only brand NAWS carries now too.

Im looking at these two because they offer dual batt charging:

http://www.batterystuff.com/battery-chargers/12-volt/gel-cell/GU16202.html

http://www.batterystuff.com/battery-chargers/12-volt/marine-chargers/TPro-220.html

but I dont know much about them, Im still trying to find details from/on the manufacturers.

I like the dual battery capabilities they have, are there others out there like these?


thanks

Comments

  • WindsunWindsun Solar Expert Posts: 1,164 ✭✭
    Re: AC to DC battery charger questions

    We can actually special order the Xantrex TruChargers, but lead times (2-12 weeks) are so bad we took them off the website.

    Aside from that, you also have to consider altitude - generators lose a few percent output power for every 1000 foot of altitude. I forget the exact number, and it varies with the generator, but somewhere around 2%.
  • mike95490mike95490 Solar Expert Posts: 8,470 ✭✭✭✭✭
    Re: AC to DC battery charger questions

    The Power Factor of the Charger also matters, the closer the power factor is to 1.00, the more of the generator output can be used. Here's a thought sure to stir up something - what's the PF of the inverter output of the genset?

    Will the charger be a full time charger, or just for Bulk? Many Automotive chargers can stuff a bulk charge into the batteries, but it's the finishing charge they fail at.
    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 ,

  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions
    Windsun wrote: »
    We can actually special order the Xantrex TruChargers, but lead times (2-12 weeks) are so bad we took them off the website.

    Aside from that, you also have to consider altitude - generators lose a few percent output power for every 1000 foot of altitude. I forget the exact number, and it varies with the generator, but somewhere around 2%.

    mabey this post is related to the long lead times?
    http://forum.solar-electric.com/showthread.php?t=6734

    altitude compensation, good tip!



    Ive read some good things about samlex and they have some dual battery chargers and just found these to add.

    http://www.batterystuff.com/battery-chargers/12-volt/gel-cell/SEC12-15.html

    this one looks really nice: http://www.batterystuff.com/battery-chargers/12-volt/marine-chargers/SEC12-45.html
    just wondering if the Honda 2000 will run it continuously?


    most attractive for my aplication is this one:

    http://www.batterystuff.com/battery-chargers/12-volt/marine-chargers/DPPS2.html

    its waterproof and that greatly expands the mounting posibilities in my case (RV) also made in the USA and 3year waranty.
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions
    mike90045 wrote: »
    The Power Factor of the Charger also matters, the closer the power factor is to 1.00, the more of the generator output can be used. Here's a thought sure to stir up something - what's the PF of the inverter output of the genset?

    Will the charger be a full time charger, or just for Bulk? Many Automotive chargers can stuff a bulk charge into the batteries, but it's the finishing charge they fail at.

    another good tip, something else I havnt heard of. should also help determining what the best set up would be.

    I would like to learn more and be able to determin what the best charger available is to run off the Honda 2000. dual battery capabilities is not really a requirement in my case, it would be useful but I would rather have the best most compatible charger for the Honda 2000 so that I could get the most from the amout of fuel used.


    over-all reliability of the charger in the long run is the main thing for me though.


    thanks
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions

    The Honda is reasonably fuel efficient from 25% to 100% of rated load (1,600 watts).

    I am going to guess that the Honda eu2000i is both Watt limited and VA limited...

    Assume a good quality 80% efficient battery charger outputing 15 volts to the battery bank and a PF=1 (the new TC2 from Xantrex I think is PF corrected--plus some of their other combo inverter/charger units may be PF corrected:
    • 1,600 watts * 0.80 * 1.0 pf * 1/15 volt batt = 85 amp 12 volt charger maximum (PF corrected)
    • 400 watts * 0.80 * 1.0 pf * 1/15 volt batt = 21 amp 12 charger low end (PF corrected)
    If you assume PF=0.6 for a reasonably;ly poor-average battery charger (note, the second equation below could use 1/PF to allow for the fact that the wiring sees the higher current and may limit other loads such as power tools and such--but the gas motor only sees the "real" Watts required to run the alternator/inverter):
    • 1,600 watts * 0.80 * 0.6 pf * 1/15 volt batt = 51 amp 12 volt charger maximum (poor PF)
    • 400 watts * 0.80 * 1.0 (don't care) pf * 1/15 volt batt = 21 amp 12 charger low end (poor PF corrected with efficient fuel flow at 1/4 power load)
    I hope the above makes some sense.

    -Bill

    PS: This is a good time to remind everyone that the Kill-a-Watt meter would be perfect to use here (of course--if you don't have the charger and a test load--it is a problem).
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BrockBrock Solar Expert Posts: 633 ✭✭✭✭
    Re: AC to DC battery charger questions

    What Bill said and I can't say enough good things about iota chargers. Assuming your running 12v I would think the DLS-30 would be a good match for your batteries and let the Honda idle down a bit reducing noise. The Honda would likely run the DLS-45, but it would be closer to the top end and the genset wouldn't throttle down, which is ok, but louder and the DLS-45 would be oversized for your batteries as well.
    3kw solar PV, 8 L16's, xw 5548, Honda eu2000i, iota DLS-54-13, Leaf EV, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    thanks BB, as usual I will have to read your post several times before I can even start to understand it but thats not your fault and I allways look forward to your replys in my posts! just wish I could understand more than half of them.

    but at a glance it it seems to indicate I would be safe to assume the 2000 will run most any 12v charger upto 45a. (I think)


    thanks Brock, that brings me to another question. what would be best as far as getting the most out of the fuel used, a higher amperage and revs or a lower amperage/lower revs?

    not taking the batteries capacities into consideration except than they will allways be 12v since they may change and I prefer to have as many options available to me as possible in that regard. or would the battery capacities be a factor in determining fuel efficincy?
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions

    Basically, that is my guess doing the math... If others have real world experience (what's that?)--I will differ to there experience.

    Regarding the math... Basically, assuming PF=1:
    • Generator Watts * eff of charger * 1/battery charging volt = "available amps at battery"
    If you assume PF=0.6 ... Then you assume that only 60% of the amps*volts is converted into useful power (DC amps*volts) at the battery (maximum generator AC current but inefficiently used at battery charger because of "poor" power factor). So, this limits the maximum size of the charger.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • RandomJoeRandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: AC to DC battery charger questions

    I have a 55A 12V Iota, and it runs just fine on my EU2000i. It's been a while since I measured it with the Kill-A-Watt but I'm pretty sure it was in the 1100-1200W range according to that. Comfortably low enough that I knew I could keep the fridge on with it, but wasn't going to be running much else at the same time. The eco-throttle actually backs off a bit while running it.

    I will note (in relation to a similar Iota thread that's running now) that the Iota generates one heckuva big arc when plugging it in, if the socket is already hot. Some substantial inrush to charge the caps I guess, but still the generator doesn't seem to mind at all. I have taken to using a switch to turn it on/off, rather than just plugging it in!
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions/add "gasoline" statement

    Regarding optimum genset fuel usage... Very roughly, most generators are most fuel efficient from 50% to 100%+ of rated load. What happens below 50% of rated electrical load, the generators typically use ~50% fuel flow...

    The Honda eu2000i (and some other inverter/generators) because the motor can slow way down at low power output (internal inverter in "generator" gives 120 VAC at 60Hz even if the motor is running slower). So, for the eu2000i, even running at 25% of rated load is still pretty fuel efficient.

    Another issue is that diesel gensets really run best at 50-60%+ of rated load for best mechanical life (other thread).

    So, the previous equations give you ideal load calculations (for chargers, pumps, etc.) on your genset.

    Battery wise, the ideal charging current runs from 5% - 13% or even 30% of the 20 Hour Amp*Hour capacity of the battery bank (these are rules of thumbs--always check with the mfg. data sheet for actual numbers).

    So, the optimum maximum size for a random battery charger is 51 amps (12 volts) on a Honda eu2000i (not PF corrected). That would give you a range of battery AH capacity of:
    • 51 amps * 1/0.05 = 1,020 Amp*Hours (12 volt battery bank)
    • 51 amps * 1/0.30 =170 Amp*Hours (12 volt bank)
    The minimum "optimum" battery bank would be:
    • 21 amps * 1/0.05 = 420 Amp*Hours (12 volt battery bank)
    • 21 amps * 1/0.30 =70 Amp*Hours (12 volt bank)
    So, ideally your battery bank for 3 days no sun and 50% maximum discharge times your daily load (6x daily load AH or Watt*Hours),--you would then look at the charger size to fit that range... And then look at the genset size to efficiently support the chosen charger.

    One thing to remember is that batteries will take maximum charging current up to ~80-90% State of Charge (Bulk charging). The Charger's current (and power usage) will drop as the state of charge continues to increase (Absorb charging).

    The aborb will continue down to ~2% of maximum charge rate, at which time a charge controller would switch to float charging.

    The absorb, as the current drops, will pull less watts from the generator and may drop you into the fuel inefficient range (below 50% or 25% fuel use--depending on brand/model)... At that point, you will either let the solar panels finish the charging, or you may choose to stop the genset and call 90% "full" as good enough (and it really is except when you want to try equalization which, typically is done once a month more or less, and done at ~5% * AH rating of the battery bank -- and you will know is fuel inefficient (but only done on the genset rarely).

    Note, a 1,600 watt genset can support a pretty large battery bank (even more if Power Factor Corrected charger is used).

    One of may rants is to really choose the best generator size/brand/model to support your needs. That 15kW diesel looks really nice (10-30,000 hours between overalls)--but if you are only using a 1 kW most of the time--you are just pouring expensive fuel down its injectors for little return.

    Placing a Kill-a-Watt meter (or other Watt*Hour Meter) on the output of your genset and keeping track of fuel used (gallons, pounds, cuft, gasoline, diesel, propane, natural gas) will let you calculate the kWhrs per gallon usage...

    From what I have seen, a smallish portable genset will give you roughly 5-6kWhrs per gallon of fuel [that is per gallon of gasoline--other fuels/gensets will be different].

    Take a large genset with 50% break point, and run it at 25% load, all of a sudden, you are getting ~2.5kWhr / gallon of fuel--and spending 2x in fuel costs for the priveldge.

    I hope this makes sense (at least it made sense in my head while typing it :roll:).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    what about using a AC to DC charger that puts out more amps than my solar charge controller is rated at, is that a problem? does the solar charge need to be off when charging with an AC to DC charger?


    I dont understand Power Factor Corrector/correction. seems to be an optional gizmo on some chargers but what is it doing exactly?


    the Iotas should come with a built-in on/off switch and the jumper wire for reducing output is pretty slack and they dont look too portable either. I havnt ruled them out though.


    thanks
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions
    what about using a AC to DC charger that puts out more amps than my solar charge controller is rated at, is that a problem? does the solar charge need to be off when charging with an AC to DC charger?
    You can place each charger (and breaker/fuse) to the main battery bus (short, heavy gauge wire, low voltage drop). You will have some interaction (one controller may go into float while the other is still in Absorb)--but those will not cause issues.

    The one major issue is if you have a big 30% rated AC charger and a 13% solar charger and flooded cell batteries--you could overheat them if both chargers were on maximum at the same time (full sun, equalize, etc.).

    Check your battery's charging specification and don't pump too much current in.

    Because you are using a generator--you will not overcharge (say AC charger does not have float mode)--because you will only charge until full (or even 90% full), then shut the genset down... You will NOT have have weeks and months of AC charger holding the batteries at 14.6 volts with no cycling vs having the charger plugged into a utility power outlet). If you do take the batteries "home" for a few months... Just charging them every month or two with a single state/two stage charger is just fine.
    I dont understand Power Factor Corrector/correction. seems to be an optional gizmo on some chargers but what is it doing exactly?
    Basically, the old battery charger have a diode (full wave rectifier) charging the battery bank... And this causes zero current flow just until the AC sine wave is very near the peak voltage--then there is a short surge of current into the battery, then nothing until the next peak. The current wave form sort of looks like this:
    [FONT=Fixedsys]      /\
         /  \ 
    ----/    \---------\    /------
                        \  /
                         \/[/FONT]
    
    This "non-linear" current wave form causes all sorts of issues. The basic one is this... One of the formulas for power is P=I^2*R (I squared times R or current squared times resistance). This is the formula used to calculate resistance heating. Notice that when the current doubles, the amount of heat goes up 2^2 (two squared) or 4x... That current spike is narrow but very high... So it cause heating in the wiring (and more losses in transformers and generators too).

    That is a battery charger with a poor Power Factor (uncorrected Power Factor).

    A power factor corrected battery charger basically has the current following the voltage wave form (sine waves in phase). This is the most efficient method to transfer AC power.

    You can represent Power Factor as a decimal number... Basically PF=1.0 is a perfect voltage/sine wave form that transfers 100% of the energy.

    PF=0.5 means that only 50% of the AC current that is going through the wires is transferring energy. The other 50% of the AC current is doing no useful work--but heating wires and transformers.

    PF that is 0.95-1.0 is pretty much perfect energy transfer. PF=0.6 and below is pretty bad. Basically the wires, tranformers, and generators have to be 1/PF=1/0.6=1.67 time larger to charge the battery as a PF=1 battery charger would have to be.

    Note, the motor will still use (roughly) the same amount of fuel--there is no extra work being done (other than the bit of extra heat wasted in the wiring and generator windings).

    Bad PF limits you to using smaller battery chargers for a given generator size. Good PF allows you to use the maximum available power from your genset (or inverter, etc.).
    the Iotas should come with a built-in on/off switch and the jumper wire for reducing output is pretty slack and they dont look too portable either. I havnt ruled them out though.
    I am not quite sure I understand your question... Iota is a very solid and reliable charge controller (but probably not PF corrected). I don't think they have an AC power switch.

    But I have no experience with Iota--so I will leave it to others who can answer those questions better.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    that wasnt really a question on the IOTAs just an observation.



    so Power Factor Corrected as opposed to not PFC is much like Pure Sine Wave/Modified sine wave. more "pure" got it.

    unfoutunately none of the specs Ive been looking at mention PF or PFC or Power Correction at all for that matter. definately something I would like to have though.


    does anyone know of a charger that IS PFC in the 25- 45a output range?


    I have a shumaker 75a/12a/2a automotive type charger. its just basic charge, mabey two stage. I could use it and after thinking about it I really only need one for bulk charging anyway since the solar charge controller is PVM and has maintenace charge capabilies.

    still like to find out what the best charger would be to pair up with a Honda 2000 for all purpose 12v charging.



    heres another odd question.

    could I input an AC to DC 12v/ 25a charger output into the 25a solar charge controller directly (unpluging the PV of course) and let the solar charge controller handle the control/regulation? might have to call morning star but it seems possible and if it is I could probably get by with a really basic power supply then.
  • mike95490mike95490 Solar Expert Posts: 8,470 ✭✭✭✭✭
    Re: AC to DC battery charger questions

    I have a shumaker 75a/12a/2a automotive type charger. its just basic charge, mabey two stage. I could use it and after thinking about it I really only need one for bulk charging anyway since the solar charge controller is PVM and has maintenace charge capabilies.

    still like to find out what the best charger would be to pair up with a Honda 2000 for all purpose 12v charging.

    Sounds like you have one - shumaker 75a/12a/2a


    heres another odd question.

    could I input an AC to DC 12v/ 25a charger output into the 25a solar charge controller directly (unpluging the PV of course) and let the solar charge controller handle the control/regulation? might have to call morning star but it seems possible and if it is I could probably get by with a really basic power supply then.

    I would say NO. The charger looses 2V in the charge controller, that's one reason 12V PV panels output 17 - 19V, to offset the loss. Putting a automotive or an IOTA charger into a PV controller, you will only get the first half of BULK, and then only if the batteries are really low.
    and:
    If you had a 17V DC power supply, with only a little bit of ripple, that may work, but the automotive chargers have no filter, and the pulsing DC may do strange things to the charge controller.
    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 ,

  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    new question. can I leave the charger permanently connected to the battery while it is unpluged from the AC source?

    now Im considering a hard wired install where I would just need to plug into AC when needed.

    I will consult with the manufacturers also as it may be different for each type of charger but I dont know so I ask here first.

    if I go the hard wired route then the largest battery that I would need to charge is 230ah and the smallest is 100ah, both are AGMs.

    Im still trying to determin the best size charger to combine with the 2000i generator for maximum fuel efficiency/run time.

    Im guessing about a 40amp charger would be best because according to the specs BB posted earlier, with 51amps it might be too much for the 100ah AGM.


    as I mentioned I like the waterproof, dual output units but after thinking about it I dont need the dual capacity because the way I have this system set up is one of the batteries is a switched back-up (the 100ah) so I cant drain them both simoultaneously and therfore theres no need to charge them simoultaneously (surely I mis-spelled that LOL)


    another question (for the IOTA owners) do they seem they would be OK mounted in an engine compartment? it would be dry for the most part but still "outside" 24/7


    thanks

    edit: I just spoke with IOTAs rep and it is OK to have it hard wired and unplugged from AC source and it is OK hardwired with active solar charge controllers too.

    but engine compartment install is discouraged due to heat and debris.
  • RandomJoeRandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: AC to DC battery charger questions

    No, I wouldn't mount my Iota in an engine compartment. Lots of cooling slots, and a cooling fan on one end. It would definitely get gunk inside!

    Mine is hardwired (through a breaker and fuse) to the battery bank, I just plug it in when I need it. Since I don't need it very often, I do generally turn the breaker off when not in use. I might not bother, if I went to the trouble to determine if it has any parasitic current draw when off - but I haven't done that. (There'd at least be a touch, as the indicator LED stays on all the time it's connected to the battery bank and not charging. Flashes during charge.)
  • dwhdwh Solar Expert Posts: 1,341 ✭✭✭
    Re: AC to DC battery charger questions
    new question. can I leave the charger permanently connected to the battery while it is unpluged from the AC source?

    My old camper van has a Shumacher 10a hard wired to the aux battery. It was like that when I got it, and there haven't been any issues with it.

    I will be replacing it with a bigger Iota down the road when I replace the single (underhood) aux battery with a pair of AGMs mounted in the cabin.
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    hey guys,

    I think Im going to go with an IOTA. too many good words and I can reach a human there for support if ever needed.

    now I need to decide between the 30a http://store.solar-electric.com/dls-30.html

    and the 45a http://store.solar-electric.com/dls-45.html

    the only difference besides the extra amps in them I see is the 45 can charge @ 14.2vdc and the 30 only 13.6vdc.


    I think I would be better off with the 45a. I dont have any gel cell batteries, only AGMs but one of them is only 100ah. I dont have and cant attain charging specs for this one because the local dealer says he doesnt have any. Im not even sure what brand it is but I have learned more since that purchase and wont be buying from this place again.

    I think the 14.2vdc would be best for AGM, right? but is 45a charge OK or too much for an average 100ah AGM?


    thanks
  • BrockBrock Solar Expert Posts: 633 ✭✭✭✭
    Re: AC to DC battery charger questions

    They both have the same output voltage options. Either 13.6 without the jumper in place or 14.2 with it in place or you can get a "smart" jumper to turn it in to a automatic 3 stage charger.

    For a single 100a battery I would say 45 is too much, heck even 30 is a lot. But if you have 15 amps of load running at the same time that 45 amp charger will get 30 amps to the battery.
    3kw solar PV, 8 L16's, xw 5548, Honda eu2000i, iota DLS-54-13, Leaf EV, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions

    The batteries should reduce their amperage draw pretty quickly as the 14.2 volts is not that high (heck, my car alternator is rated at 70-100 amps or so at ~14.2 volts).

    I believe the current limits are really more based on pumping the current in at 45 amps no matter the voltage (current limit based charging)... If you find the current is too high (I don't think you will--but I do not now for sure), you could always cut back to 13.6 on the bigger inverter. A better voltage to "float" a full bank at anyway (AGM or Flooded Cell).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions
    Brock wrote: »
    They both have the same output voltage options. Either 13.6 without the jumper in place or 14.2 with it in place or you can get a "smart" jumper to turn it in to a automatic 3 stage charger.

    NAWS shows only the 45a IOTA having output voltage options but I see after looking at IOTAs site they both do.

    the 13.6v output, is that just for when you charge gel batteries?
    Brock wrote: »
    For a single 100a battery I would say 45 is too much, heck even 30 is a lot. But if you have 15 amps of load running at the same time that 45 amp charger will get 30 amps to the battery.

    I wouldnt be charging the 100ah AGM routinely with the 45a charge, its a back-up battery only but I would like to be able to use the 45a charger for it. I did not consider that I could have a load on it while charging.

    I think the Honda 2000i generator combined with the IOTA 45a charger would produce more electricity per gallon of fuel used than it would with the IOTA 30a, right? thats why Im asking so many questions..


    I wish they made a variable or switched output charger. so far they all seem pretty limited. what I have noticed is that all the different brands Ive found so far are ALL MADE IN USA. I wonder why/how the Chinese etc. havnt invaded the 12vdc charger market like pretty much all the rest.
    BB. wrote: »
    The batteries should reduce their amperage draw pretty quickly as the 14.2 volts is not that high (heck, my car alternator is rated at 70-100 amps or so at ~14.2 volts).

    so its not just a steady 30 or 45 amps from these units until the battery is charged then? I get 14.8v from the altenator at startup then drops to a stedy 14.5v everyone says thats high but its been working for several years, I never knew the output untill I installed the battery monitor recently.
    BB. wrote: »
    I believe the current limits are really more based on pumping the current in at 45 amps no matter the voltage (current limit based charging)... If you find the current is too high (I don't think you will--but I do not now for sure), you could always cut back to 13.6 on the bigger inverter. A better voltage to "float" a full bank at anyway (AGM or Flooded Cell).

    -Bill

    so it IS a steady 30 or 45 amp output untill the battery is charged then?
  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions

    From here for the DLS 45:
    [FONT=Arial,Helvetica]The DLS-45 Power Converter/Battery Charger from IOTA Engineering converts nominal 108-132 AC voltage to 13.4 DC voltage for both DC load operation and 12V battery charging.

    As a power supply, the unit's tightly controlled regulation allows the user to operate a nominal 12VDC load up to 45 amps.

    As a battery charger, the unit will maintain the battery, delivering its full-rated current when the battery capacity falls sufficiently low. The voltage is set to deliver its maximum current for the necessary period of time to minimize undue stress to the battery caused by heating of its cells. This helps to ensure the longest possible life of the battery. Over time, as the battery nears its full capacity, the DLS-45 will automatically drop the current, providing a float-charge to the battery to prevent self-discharge of the cells. [/FONT]
    From the manual (PDF):
    TWO-STEP VOLTAGE JACK
    The two-step voltage jack allows switching from a long-term float voltage of 13.6vdc up to 14.2vdc. When the included dual voltage plug is inserted in the jack*, the voltage rises to 14.2vdc for occasional fast charging. When the plug is removed, the voltage drops to 13.6vdc to reduce battery water loss.

    WARNING: To avoid battery damage, remove the Dual Voltage Plug when quick-charging is complete. NOTE: If the unit is equipped with an internal IQ4 smart charger, two-step charging is not needed and the Dual Voltage Jack is disabled.
    The IQ-4 Module:
    [FONT=Arial,Helvetica]Take your DLS Battery Charger to the next level...

    The IQ Smart Controller offers automatic charging control for DLS Battery Chargers, providing longer and safer use of your system's battery. The IQ Smart Controller is compatible with any DLS Battery Charger model and is covered under our standard Two-Year Warranty.

    [/FONT][FONT=Arial,Helvetica]The IQ Controller allows the DLS Charger to operate as an automatic 3-stage "smart charger." This gives the customer the benefit of Bulk, Absorption, and Float stage charging, increasing the charging capacity of the DLS charger and decreasing charge times, insuring proper and safe battery charging and minimizing over-charging. This "smart" technology monitors the battery at all times. If the DLS voltage remains in the long term stage for more than seven days, the IQ will automatically deliver a boost charge for a predetermined time, then automatically return to the normal float stage.[/FONT]
    IQ-4 voltages (only 12 volt listed):
    PREDETERMINED VARIABLES FOR OPERATION
    Battery Voltage 12V:
    [FONT=Fixedsys]Bulk  Absorption Float Low Trig High Trig Over Voltage 
    14.8V    14.2V   13.6V  12.8V     14.6     15.2[/FONT]
    
    • So, Option 1 would be standard DLS with no IQ-4 module.
    You put the plug in and it charges at 14.2 volts--if battery is below 14.2 volts, will hold 45 amps until battery reaches 42 volts. Once battery is at 14.2 volts, current will ramp down to zero amps (if needed) to maintain 14.2 volts

    You come by a little later and pull the plug (or wire in a switch) to put on 13.6 volt float. Controller will output 0-45 amps to maintain 13.6 volts.

    • Option 2 is DLS with IQ-4 module. (from the IQ-4 Manual):
    OPERATION OF THE IQ4 IN THE 3-STATE MODE

    BULK STAGE - During this state, the charger will operate either at Full Current output or Constant Voltage output depending on the discharged state of the battery. A discharged battery will dictate the voltage and force the charger into constant-current operation. As the battery charges, the charger transitions to a constant-voltage operation. This BULK STAGE will continue for either 225 minutes or until the battery voltage reaches the “High Trigger” value (whichever occurs frst). At this point, the BULK STAGE will operate for another 15 minutes before switching to the ABSORPTION STAGE.

    ABSORPTION STAGE - This state is limited to 480 minutes (8 hours) during which the charger will operate either at Full Current output or Constant Voltage output depending on the discharged state of the battery. During Full Current output, the charger is providing its full current rating and will slowly increase the battery voltage to the “Absorption Stage” voltage. At the end of the 480 minutes, the charger will revert to the FLOAT STAGE.

    FLOAT STAGE - This charge state holds the batteries at Constant Voltage for a period not longer than seven days. During this state, the charger not only foats the batteries, but it can also provide load current up its maximum rating for other loads without depleting the battery capacity. The FLOAT STAGE will end when either the battery voltage drops below the “Low Trig-ger” point or at the end of seven days when the IQ4 initiates an equalization stage to remove sulfate layers from the battery plates. In either situation, the unit exits the FLOAT STAGE and enters the BULK STAGE.
    And Equalize:
    If the battery has remained in the Float State for seven days, the IQ4 automatically provides an equalization charge to dissolve any sulfate layer on the battery’s plates and to avoid stratification.
    The "Equalization Charge" is the worrisome part for me regarding AGM/Sealed batteries...

    Nowhere is the EQ Voltage listed. And nowhere is the EQ time/algorithm listed.

    If you are OK with manual operation of the voltage plug--the two voltages 14.2v/13.6v for Bulk/Absorb and for Float should be fine with AGM batteries (assuming you turn off the 14.2 volt charging setting at the end of a charge cycle.

    The IQ-4 is not really clear enough for what it does with EQ mode every 7 days... And the 14.8 volt Bulk / 14.6 volt high trigger seems to be a bit hot for an AGM battery.

    On their website--I could find nothing regarding AGM's and proper operation with their chargers. I would either ask Iota more details on the IQ-4 and any issues with AGM batteries and/or just go with the manual mode. 14.2 volts should not be a problem for AGM until they are fully charged and you are ready to manually switch to float.

    -Bill :confused:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BrockBrock Solar Expert Posts: 633 ✭✭✭✭
    Re: AC to DC battery charger questions

    That’s odd. As far as I can see, on mine at least the IQ4 just switches between the "jack in" or 56.8 (14.2) and "jack out" or 54.0 (13.5) in my case anyway. It never gets above the 56.8 or at least the trimetric never sees it get above that charging with the iota when using the IQ4.

    Basically you can think of the jack as a bulk voltage when plugged in and a float when it is out. For intermittent use I would just do it manually and ignore the IQ4

    And as Bill said once you hit the voltage you have it set for the amperage drops off to maintains that voltage.

    I am not sure fuel wise if you’re better off with the 30 amp or 45 amp version. The more I think about it I would go with the 45 amp version. It would mean running the genset less to get the battery bank charged back up and if you’re drawing any load you would have more left over to keep charging the battery. For instance say you have your 100amp battery powering your inverter, which is powering a computer. So that might be pulling 150watts to run. Now you turn on the genset and charger and let it go. The inverter stays on powering the computer pulling 150w or about 15 amps at 12v from the battery. Now you still have 30 amps charging the battery and 15 amps feeding the inverter and you didn't have shut off your computer to move the plug from your computer from the inverter over to the genset and then back again when it was done.
    3kw solar PV, 8 L16's, xw 5548, Honda eu2000i, iota DLS-54-13, Leaf EV, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    Im still shopping for the right converter. so far the only one that I have found that has power correction is the Xantrex XADC 40a
    http://www.bestconverter.com/XADC-40A-ConverterCharger-_p_326.html

    I cant find any PCF info on any of the others Ive seen. I asked IOTAs rep about this and was told they do not have PCF and they run at 65%


    Im also considering this Black and Decker automotive type unit since it seems to have the most features and versatility but I havnt found a PCF. I will try to contact them about it.

    http://www.blackanddecker.com/productguide/product-details.aspx?productid=15580&toolview=7#details


    heres a very informative 5 page thread on rv.net on the subject:

    http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/22641751.cfm


    edit: I cant get a human on the phone at B&D to ask about PCF on this unit but this page has more info on them:

    http://www.boatandrvaccessories.com/VEC-1093DBD.htm

    no PCF rating but I called them and they didnt have PFC specs but mentioned that it senses long extension cord runs to the unit and can increase output when low ac voltage input is detected.

    would that be PCF?

    PCF or not its a pretty impressive unit for the price, less than half what the Xantrex retails for.

    thanks
  • mike95490mike95490 Solar Expert Posts: 8,470 ✭✭✭✭✭
    Re: AC to DC battery charger questions

    Just looked at my B&D VEC1093 40A charger, no PF spec on it

    We can assume it's a switching supply, and guess it would be in the ballpark of any 12V / 700W switcher.
    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 ,

  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    besides the switching, how does a "switcher" and non-switched converter compare?

    pros/cons?


    another thing Ive been wondering about along these lines but sorta off topic is a charger/converter for my laptop.

    a 12vdc converter/ charger adaptor is available but would running the laptop off this save enough power to consider compared to running the OEM ac to dc charger running off a suresine 300 inverter?

    thanks
  • mike95490mike95490 Solar Expert Posts: 8,470 ✭✭✭✭✭
    Re: AC to DC battery charger questions

    Switchers use a high frequency (100's of KHz) transformer, very efficient, very light weight. non-switchers have a big iron 60hz transformer in them. not quite as efficient, but only about 3 parts to go bad internally.
    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 ,

  • BB.BB. Super Moderators, Administrators Posts: 29,717 admin
    Re: AC to DC battery charger questions

    Also, there are different ways of "regulating" voltage/current/etc...

    An "analog way"--standard "3-Terminal Regulators" they have a transistor that turns on a bit more or off a bit less to balance the voltage/current output. Any "excess energy" is lost as heat. Think of a water faucet--turn the faucet more on or more off to regulate the stream out the hose... Very inefficient. But very simple and rugged.

    Then there is the PWM switching regulator--Pulse Width Modulation. Switch on 100% current/voltage output. Switch off 0% output. Use a capacitor/battery to even out the voltage/current for use down stream. Very "noisy" output. Not very efficient, but the regulator (switch) does not get hot. Cheap and simple. Think of a faucet that is either full on or full off.. Nothing in between.

    The typical "switching regulator" -- has energy storage elements (inductors and capacitors) to store the energy to supply the needed voltage/current. Can be pretty quiet and stable. More complex but very efficient (80-95% efficient). Because of the cycling nature of the "switches" -- can use small/high frequency transformers for electrical isolation--and/or use inductors to step up or step down voltage/current efficiently.

    For one example--a RAM pump... Take a long length of pipe from a small dam. Turn on the outlet valve and let the water "get up to speed" in the pipe. Now quickly shut the outlet valve. The momentum of the water wants to continue forward--but the outlet is shut... Have a second check valve to a higher water tank/storage area. The momentum of the water will carry some of the water up the pipe and into the storage tank. Once momentum is used up... Open the outlet valve again and get the water in the long pipe from the low dam flowing again... That is using the stored energy from motion to pump water up hill. Sort of how a "boost mode" type switching power supply works.

    -Bill "water analogies R us" B.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • notsobrightnotsobright Solar Expert Posts: 247 ✭✭
    Re: AC to DC battery charger questions

    thanks BB, If it wasnt for water analogies I would have mush less understanding of electricicty all together.


    I think Im gonna get the B&D charger. I dont have an equalizer or reconditioner at all so I think it would be more useful to me in the long run.
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