Question about battery charger selection with EU2000 generator.

SteveK
SteveK Solar Expert Posts: 387 ✭✭
In an attempt to not screw up my order of an Iota charger I'd like to know in advance how well it will work with my soon to arrive EU2000i generator.

I have a 450 ah 24V battery bank.
Typical DOD of 70% drawing ~1500Wh/day at 10C.

I would like to add the Iota for those 2 day without sun events instead of unplugging my chest freezer and coal stoker to allow full charging.

I would also desire the EU2000 to run at or near idle speed while charging the batts. I read another post and believe I can get there with the DLS-27-25 @ 675 watts. I desire the headroom that this would give so other items could be operated while charging the batts and also to baby the genset while charging the batteries alone.

I am under the impression that operating these generators closer to low output increases their efficiency at the expense of run time (which I have plenty of at ~8-9 hours per tank)

So all, thanks in advance and I can't wait to hear where I meseed up on my assumptions.
«134

Comments

  • hillbilly
    hillbilly Solar Expert Posts: 334 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Just a few thoughts, not really a thorough answer:

    First of all, I wouldn't rely on the Iota charger to do FULL charging or EQ charges as the voltage output is fairly low (28.4V max). This can still work out very well to bulk the batteries up a bit, just be aware of this one small detail. The other issue that you might have is that the charger takes a maximum of 12AAC, and the Honda Eu2000 has a max rated output of just over 13AAC (13.3 if I recall correctly) so that doesn't really leave much extra.

    Do you already have the honda generator? If not, I'd say that you may wish to utilize a larger one or parallel a second one for what you're proposing.
    Especially if you're running a generator, I'd personally want to shoot for a bit higher charge current too, say 40-60amps... but that's more than you could get out of a single Eu 2000.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    I will take an engineering back of the envelope shot at the answer--somebody with more experience charging battery banks with one can give you more information.
    SteveK wrote: »
    I have a 450 ah 24V battery bank.
    Typical DOD of 70% drawing ~1500Wh/day at 10C.
    Just to be clear... State of Charge of 75% would be a battery with 75% of its charge still left in it.

    Depth of Discharge of 75% would be a battery with 25% of its charge remaining...

    I am assuming you are using 30% of your battery capacity every night? So, the first night is 70% state of charge (70% full?)?

    Your battery has a capacity of:
    • 450 AH * 24 volts = 10,800 WH
    • 1,500 WH / 10,800 WH = 0.14 or 14% per day draw down
    • 2 days * 14% = 28% DOD or 72% SOC remaining
    And, we would like to limit the maximum draw down to 50% for long battery life (get recharged quickly back above ~75% to limit sulphation damage).
    I would like to add the Iota for those 2 day without sun events instead of unplugging my chest freezer and coal stoker to allow full charging.
    Assuming I am understanding you correctly--You can go 2-3 days very easily with "no sun" before needing to crank up the genset for some remedial recharging.
    I would also desire the EU2000 to run at or near idle speed while charging the batts.
    ...
    I am under the impression that operating these generators closer to low output increases their efficiency at the expense of run time (which I have plenty of at ~8-9 hours per tank)
    Actually, the Honda euX000i family just run more efficiently at lower output power than standard non-inverter based generators because they have the ability to throttle back when operating at low output. The Inverter can keep full voltage and proper voltage with the reduced engine RPM. Typical Alternators, the output frequency is directly coupled to the engine RPM. For example, small gensets 3,600 RPM=60Hz... If the engine throttled back, the alternator spins slower, and the frequency falls out of spec.

    For the Honda eu2000i: Run Time per Tankful 4hrs. @ rated load, 9.6 hrs. @ 1/4 load (1.1 gallons of fuel) (also note: Honda used to spec., 15 hours @ 1/4 load per tank of gasoline--I guess that was too optimistic :cry:).
    • 1,600 watts * 4 hours / 1.1 gallons = 5,818 WH per gallon at 100% load
    • 400 watts * 9.6 hours / 1.1 gallons = 3,490 WH [per gallon at 25% load
    So, from a cost of fuel point of view, you are better off running the Honda at higher loads if possible. Would it be better for the life of the engine to run it 6 hours at low load vs 3 hours at heavy load? I don't know--but I would tend towards running at heavier loads (just keep up with the oil changes).

    The little Honda engines last a pretty long time when compared to other small gensets (these small genset Honda engines are not really rebuild-able as I understand--scrape and get another when they fail after X,000 hours).

    Here is a nice thread: small generator questions -- In there, it sounds like you can get 1,500-3,000+ hours with a well taken care of Honda euX000i genset (oil changes every 50 hours from one user).
    I read another post and believe I can get there with the DLS-27-25 @ 675 watts. I desire the headroom that this would give so other items could be operated while charging the batts and also to baby the genset while charging the batteries alone.
    OK, 27.2 volt and 25 amp ouput... 80% efficient and 12 amps at 108 volts...

    So, from a spec. point of view, the Honda eu2000i has enough current to drive the Iota Charger at full load:
    • 12 amps * 108 VAC/117 VAC typical = 11 amps typical
    • 675 watts maximum output power * 1/0.80 efficiency = 844 watt load on genset
    Now, the battery charger will only output maximum current / power when the battery is below ~80-90% state of charge... So, you will want to monitor the charging current and battery state of charge (battery monitor) and probably cut off the genset when the charging current falls well below 10 amps (in terms of optimal fuel consumption).

    For a rough estimate of run time to full charge--assume around 1-6 hours of absorb time (the last 10-20% recharging at reduced current).

    My guess, is plan on recharging along this formula:
    • Time on Generator = AH used / Amp Charging + 2 hours
    So, for your three days of x 1,500 WH per day at 24 volts, I would try:
    • 3 days x 1,500 WH * 1/24 volt battery * 1/25 amps charging + 2 hours = 9.5 hours
    Measure the battery bank state of charge at the end of the 9.5 hours of charging (hydrometer, battery monitor, or resting voltage) and see how full the battery bank is...

    I would not aim for 100% state of charge, but at least close to 90% will be fine... If the state of charge is a bit low, then add another 1-2 hours run time and see how things look.

    Monitor the charging current at the end of the charging cycle (no use running the genset for a couple amps of trickle charging current). You have solar, so you can let it finish the charging the next time you have some good sun.

    I don't know--perhaps it is just me, but it seems to be very difficult to find a reasonable battery charger that can pump out ~29 volts to quick charge a battery bank on a genset (assuming that it not too much current for the battery)... ~27.0 to 27.2 volts seem a bit low when trying to make the best use of generator run time and fuel costs (perfectly OK for a grid powered application).

    Xantrex has some nice battery chargers that are at least 28.8 volts nominal output for charging a 24 volt bank as well as true 15/30+ volt equalization--But they are not cheap.

    The only really programmable battery chargers seem to be those that are part of the inverter/charger families of Xantrex, Outback, Magnum, etc... And all of those are not going to be cheap either.

    I do wish the Iota had an option for increasing their output voltage for those folks using gensets to push the charging current a bit harder.

    Anyone else have a better suggestion?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Question about battery charger selection with EU2000 generator.

    bb,
    recheck your math from this,

    • 450 AH * 24 volts = 10,800 AH<<<<should be wh
    • 1,500 WH / 10,800 WH = 0.14 or 14% per day draw down
    • 2 days * 14% = 28% DOD or 82% SOC remaining<<<<100-28=72
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Thanks Hillbilly,

    That's a good point. I don't want to waste generator time topping them off, just bump them up a bit to take the edge off. Most times there isn't more than a 2 day lull in sunshine here. I'm kind of prepping for some off grid experience.

    To the 12A AC spec. I'm confused by that as in order for the charger to achieve 675W at greater than 80% efficiency I was assuming the Max AC Ampere rating was some sort of inrush current only present momentarily. So I figured that number could not exceed the peak rating of the generator...not seen constantly throughout the charging process.

    I'm confused as to why my 1600W generator cant supply the 1100W of a 40A charge current. They need to make this stuff simpler for guys like me. Or Iota need to improve their efficiencies.

    I had entertained a second genny in the fall next year.

    Thanks!
  • hillbilly
    hillbilly Solar Expert Posts: 334 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Steve,
    I'm not entirely sure of exactly how much current that charger might draw during various stages of charging, I just quoted the specs that they list. And I have to say as far as listed specs or marketing; I think I'd more likely wag my finger at Honda for marketing a "2000 Watt Generator" that only puts out a max continuos current of 13.3Amps! Anyways, there are a few reasons for thinking about a larger genset, or a parallel one:
    For one thing, most of us "off the grid" folks have a very hard time affording enough PV panels to achieve that high 10% charge current that is often recommended here. I've had this confirmed by several tech support folks at Surrette batteries, they have all been adamant that for optimal health the batteries need to get charged by a sufficiently high current (these guys all felt 10% was kind of minimum) on a semi regular basis. So the ability to give them a shot of stronger current now and then can be a boost to their health.

    The other is that if you want to run some loads while trying to bulk the batteries up you need some headroom. Sounds like you did have some additional loads that you were looking at running, so you might take a closer look at them and decide what stuff you could live without for "x" amount of hours to recharge your batteries.
    Two parallel units would likely work out pretty well really, you could run two of them if you were looking to really bulk things up in a more timely fashion or after a deeper discharge. Or you could use just one if you had no major loads, or were looking to top your batteries off a bit more (we certainly have to do that from time to time in the winter). In large part due to the later reason I ended up replacing my Iota chargers with an Outback inverter/charger combo which gives a full range of charging options, with the ability to set both current and voltage levels. But as Bill pointed out, it was not a cheap option...
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    Thanks Niel, fixed (note to self: always use calculator :blush::roll:).

    Regarding Iota--Their battery chargers are not Power Factor Corrected (at least the models we are looking at here)... They probably have a current waveform with sharp peaks instead of a nice, in phase with the voltage, current sine wave...

    This causes very high peak currents which raise the over all RMS current numbers (RMS--Root Mean Square value of current). So, the non-PFC power supplies appear to take more current, but not energy... So from the numbers, Iota claims 80% efficient. And we see 12 amps at 108 volts. We can back out a Power Factor calculation:
    • Power to battery bank = Volts * Amps * Efficiency * Power Factor
    • Power Factor = Power * Efficiency / (volts * amps)
    • PF = 675 watts output * 1/0.80 * 1/(108 volts * 12 amps) = 0.65
    So, the "apparent" amount of current used by the non-power factor corrected power supply is ~1/0.65 or 1.54 increase in current draw from the genset.

    This extra 54% more current is totally unable to do any useful work... All it does is cause (I^2)*R resistive heating losses in the wiring and generator electronics.

    So to put this all in an equation:
    • P=V*I*eff*PF
    • I ac input current=P/(V*eff*PF)=675 watts output to battery / (117 volts * 0.80 eff * 0.65 PF) = 11.09 amps
    Which agreed with my earlier estimate of 12 amps*108v/117v=11.07 amps (close enough for government work / back of the envelope engineering calculation).

    Anyway, one of the other reasons I like the Xantrex TC and XC inverter (Power Factor Correction) and many of the new inverter/chargers that also have power factor correction.

    So, even though one would have expected from a "nice" AC power supply:
    • Current from genset = 675 watts * 1/117 volts * 1/0.80 power supply efficiency = 7.2 amps
    In real life with the older non-PFC power supplies (PF~0.65 in this case) we see it drawing an RMS equivalent current of ~11 amps...

    And that extra ~5 amps AC input is totally wasted. It is not doing any real "work" and you cannot use that extra 5 amps to run a washer, fan, etc... Because it is it being "used" by the power supply.

    -Bill

    PS: Thanks again Niel--2 errors in three lines... Get some sleep...:blush::blush:
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Yes sorry guys it is SOC and not DOD. I use ~30% in one overnight I think it is because of the cold temps (~10C) in the battery location leading to reduced capacity. I have verified the usage with kill-a-watt meters plus inverter losses and it is indeed ~1500w/h per day for my coal stoker and freezer.

    Well I just read all the new replies From Bill Niel and Hillbilly and it all is crystal clear to me now. I really need to select another charger and also add more generator to get both mitts around this. Seems the PFC of .65 is something I just shouldn't buy into. Spend now to save later.

    Bill, there is a jumper switch on the IOTA's that reduce the float and increase the bulk voltage to ~28+ volts. I read this somewhere that elludes me at the moment...

    Thanks guys for saving me return shipping and restocking fees if I was lucky enough to get them to take it back.

    Steve KB1TDQ
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    Steve,

    You probably need to call Iota to find out the exact operation of the DLS series...

    Yes, there is a jump. IN=charging, OUT=Float (it appears).

    The pdf manual seems to fall all over itself avoiding saying what the voltages are when the jumper is in/out.
    TWO-STEP VOLTAGE JACK
    The two-step voltage jack (located on the top of the DLS on the fan-end of the unit) allows switching from a long-term float voltage to an increased quick-charge voltage.

    When the included dual voltage plug is inserted in the jack*, the voltage increases for faster charging. When the plug is removed, the voltage drops to rated nominal voltage to reduce battery water loss. WARNING: To avoid battery damage, remove the Dual Voltage Plug when quick-charging is complete.

    NOTE: If the DLS is equipped with an internal IQ4 smart charger, two-step charging is not needed and the Dual Voltage Jack is disabled.
    However, they do list the IQ4 as having:
    float 2.26 volts per cell
    Absorb 2.36 volts per cell
    Bulk 2.46 volts per cell
    So, which of the above three voltages map to the Jumper controller output... If the Jumper=IN=2.46=29.52 volts for a 24 volt battery pack--That is a very nice high voltage for quick charging on a generator.

    If it is 2.36v*12=28.32 volts... A much more leisurely charging voltage (14.16 at 12 volt) and could end up costing you extra fuel.

    Not to pick on Iota--Finding PFC battery chargers seems to be few and far between.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    I will contact Iota tommorrow Bill and report back here. I agree the specs are confusing at best and a buy and try is out of the question.
  • E-dub
    E-dub Registered Users Posts: 13 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    It sounds like you have your question answered but I will toss in a comment about the Honda Eu2000i generator.

    We used one with an Outback VFX3648 in the "Eco" mode as a test. It worked fine as long as the charger was pulling over 6-7 amps AC but below that threshold the generator would continually surge.

    The generator didn't seem to have this problem with other small loads, just charging through the Outback inverter. The generator wasn't new and we didn't do any extensive testing to determine if the problem was with the Honda/Outback combo or if the generator had circuitry problems.

    We occasionally use a Yamaha 2400i inverter generator in the Eco mode with the same Outback and have no problems. On the other hand, we use a Yamaha 1000i for battery charging at the work site. If we have both the Rigid NiCad and the Li-Ion battery charger plugged in and use the Eco setting, same surging problem occurs.

    Just an interesting thing we have noticed about the "i" generators and battery chargers.
  • hillbilly
    hillbilly Solar Expert Posts: 334 ✭✭
    Re: Question about battery charger selection with EU2000 generator.
    E-dub wrote: »
    It sounds like you have your question answered but I will toss in a comment about the Honda Eu2000i generator.

    We used one with an Outback VFX3648 in the "Eco" mode as a test. It worked fine as long as the charger was pulling over 6-7 amps AC but below that threshold the generator would continually surge.

    That's interesting. We have an Outback VFX3524, and a brand new Honda Eu2000i, and haven't noticed any such issues on our set up. Quite the opposite, we've found that this combo works really smoothly and allows us to charge and run some moderate loads on very little fuel. We mostly use it when our batteries haven't had a full charge in a while due to extended stormy weather (or to do an EQ charge), as it allows us to run down to reduced charge currents for longer hours without sucking up tons of gas.
    I think at some point down the road I see a second Honda Eu2000 parallel unit in our system, as the fuel consumption per KWH is so much better than our "Beast" .
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    Re: Question about battery charger selection with EU2000 generator.

    As for surging with the EU2000i I will guess that it was an older 2000i or one with hours on it. They work fine when new on any charger. There is alot of info out there on how to get them to run smooth again. I had a customer that was determined to make an older unit run smooth again and he did everything on the Yahoo forum including replace the carbeurator. The best guess was either engine power loss or an inverter issue. He then replaced the engine and it still did it. Just an FYI. There comes a time when you have to replace the unit as you can not have that kind of surging on your loads, for long!
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    From another forum I read (candlepowerforums.com) this place came recommended for good pricing on Honda eu2000i motor replacement parts (I don't know anything about the vendor myself).

    Boats.net

    And this is probably the Yahoo forum for eu2000i owners that Dave was typing about.

    eu2000i forum

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Thanks again all for the discussions. Tis why I am here everyday to learn the straight skinny on this stuff.

    I just got off the phone with Iota. They confirmed the DLS-27-25 can be switched into higher voltage mode via a jumper. The output voltage would be ~29.5V while reducing the charge current to compensate the compliance wattage of 680W.

    So ~23A @ 29.5V.

    They also verified that it needs 1300W Max in to produce 680W out....so much for the EU2000i palatial headroom....:p

    Bill. I think you were pretty close no? Like .2% off? heh...

    What do you all think of going the Trace TR-3624 route? Seems as though the PF is much better and the charge current would be adjustable from 20-70A to suit my needs.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    The TR inverter/charger is a MSW type inverter... Is that OK with your loads/needs?

    MSW is the equivalent of High / Bad Power Factor in the inverter world. Thinks can work OK (and lots of people are happy with their MSW inverters -- modified square wave inverters)--Or there can be a bunch of nagging issues. Really depends on your needs.

    A couple of Inverter FAQs:

    All About Inverters
    Choosing an inverter for water pumping

    MSW is sure a heck of a lot less expensive--Always a concern.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • E-dub
    E-dub Registered Users Posts: 13 ✭✭
    Re: Question about battery charger selection with EU2000 generator.
    As for surging with the EU2000i I will guess that it was an older 2000i or one with hours on it. They work fine when new on any charger.

    Yes the Honda had some hours on it from what I remember. I had always wondered if it was the Honda/Outback combo. Good to know that it most likely isn't. Of course it wouldn't quite explain why the Yamaha 1000i surges in the Eco mode only with a NiCad and Li-Ion charger, but works fine with either separate? That's a question for another day.

    Rick
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    Surging is probably understandable... Many "modern loads" are constant power devices:
    • Power = Voltage * Current
    And with an inverter type output on the genset--perhaps the get into a unstable feedback loop with changing current / voltage of the loads.

    Next time you have a chance, try measuring the AC voltage / Current between the genset and the load and see if the hunting is tied to the output voltage... Try placing a 50-100 watt light bulb on the output with the charger and see if it changes the surging.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • E-dub
    E-dub Registered Users Posts: 13 ✭✭
    Re: Question about battery charger selection with EU2000 generator.
    hillbilly wrote: »
    We mostly use it when our batteries haven't had a full charge in a while due to extended stormy weather (or to do an EQ charge), as it allows us to run down to reduced charge currents for longer hours without sucking up tons of gas.
    .

    Exactly what we were trying. Heavy charge with the 8kW Northern Lights and then top-off with the little economizer unit. Nice way to go.

    Steve, as for the Trace TR-3624, inverter with battery charger for around $1.2K. Probably do the job for some apps but be careful to check every appliance/device that will be hooked into it. Modified sine wave can prove the old saying "penny wise and pound foolish", not saying it is foolish to use a MSW inverter, just saying be careful.

    Call me squeamish but I am a sine wave guy figuring that a couple of destroyed appliances will soon add up to that extra few hundred dollars spent on the VFX 3648 hanging in the garage.

    Rick
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Bill and E-Dub

    I was thinking of the Trace for it's charger only. The MSW inverter could be useful in a pinch but I really don't envision any loads to actually need it.

    Just the charger @ 93% efficiency with a PF of .8. I guess the rest of it would be waste.

    Time for an Outback I suppose.
  • E-dub
    E-dub Registered Users Posts: 13 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Steve,

    I was looking at the Trace for the inverter but I see you have a good inverter already with the Exeltech. Sorry, I got off track there.

    I thought about the idea last year of getting a stand alone charger but decided to save up some $$ and add a second Outback VFX 3648 when able, to get increased charging capacity. My reasoning is for redundancy though. I'm in Alaska which as you may know, isn't part of the USA in the eyes of some company shipping departments. Plus, a failure in the winter always seem twice as hard to work with up here (perception maybe). I would prefer to not have to run the generator for days on end while waiting for package delivery with an inverter to slowly work its way out to the homestead.

    You would think there is a decent stand alone charger somewhere out there but I didn't find one previously in my very brief search, sorry to be no help here.

    Rick
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Well I think I've found a real cost effective and quality solution here:

    http://www.quickcharge.com/Images%20and%20PDF's/Select%20a%20Charge%20portable%20and%20stationary/select-a-charge%20portable%20lit.pdf

    This charger will do 40A at 30V using only 11A 117V AC. I am a bit concerned about it's programmable charging profiles though. Here they are:

    Selectable Charge Profiles:
    F1 - Float: Battery voltage rises to 2.3 volts per cell max before dropping into a low float of 2.26

    F2 - Gas & timed shut off: Timer trips at 2.3vpc, gassing threshold. Batteries are allowed to gas to a maximum of 2.55vpc before shut off. Programmable recycle time. Best for deep cycle batteries

    F3 - Gas & float: Timer trips at 2.3vpc gassing threshold. Batteries are allowed to gas to a maximum of 2.55vpc before dropping into indefinite float of 2.26vpc. Best for deep cycle batteries where an indefinite maintenance charge is desired.

    F4 - AGM: Batteries bulk charge to 2.3vpc, and enter absorption cycle where voltage is allowed to climb to a maximum 2.45vpc before dropping into indefinite float of 2.26vpc.

    F5 -Lithium Ion: Can be set to a specific voltage and will shut off when current falls to 10% of charger rating.

    For $475.00 delivered it seems like a dream come true? Completely field serviceable as well......

    E-Dub I too like the redundancy. I've got another Exceltech 1100 in reserve at the moment.

    Well whaddya guys think?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    Looks interesting... Has a battery temperature monitor (important if you are going to "push" the batteries or the bank is subject to temperature extremes. Nice high charging voltage of 2.55 volts per cell (30.6 volts). The F5 allows you to program your voltage set point--may be useful for optimizing your lead acid charging.

    Questions I would ask:
    1. AC Operating current seems like it may be Power Factor Corrected... Is it? What is the VA rating of the charger? I am not sure that it is (usually PFC is a wide range input from ~100-264 volts and covers 50/60 Hz with a single unit--these do not seem to have that ability).
    2. What is the min/max input voltage range for proper charging (at full load)?
    3. Programmable set voltage and gassing times?
    4. Can F5 be used to charge 24 VDC lead acid with adjustable set point voltage?
    5. Can unit be left connected to battery bank when AC power (generators) are off (what is leakage current through charger)? Since it is designed for on-board charging (manlifts, etc.)--I would guess it should be fine permanently connected to your battery bank.
    6. What is the frequency range it will accept (i.e., 60 Hz +/- 1%, or 54-66 Hz for non-inverter style generator?
    Assuming reliable charger from a reliable company (and the above questions are answered to your satisfaction)--Looks like would work very nicely for your needs.

    At least one of the other general purpose models reads charging current... If you do not have a Battery Monitor or other current monitoring device--it might be nice to have so you can check/adjust your charging time/profile to minimize fuel usage (units usually turn off/go to float at 20% charging load current).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Great questions there, thanks for those. I too was eyeballing the F5 programming as the target profile for my needs. I like the fact it does do Lion but don't see the value in my requirements and would rather customize F5 to suit them.

    I would say there is some calibration required on manufacture of this specific model in their product line as the lead time is 3 weeks for this model only. The others are shipped from stock. Might be why the specs are narrower than you sre used to. We will see...

    I really hope this works out because I like having seperate modular blocks for each component in the system. i.e. "one light goes out they all go out" is not where I want to be if I can help it.

    I do need an ammeter Bill for sure. I hope to get a trimetric soon. I will ask of the other comparable models with meters tommorrow.

    Thanks all!
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    Just one last warning (I don't think I said this regarding your project)--Charging your battery bank > 30 VDC may exceed the input voltage limit for some devices (inverters may shutdown, possible damage to others).

    You may have to install a battery bank switch to allow you to disconnect sensitive loads during fast charging... There are also other options (run loads on bank A while fast charging bank B, etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Yep Bill I was aware of exceeding max voltages with DC items. Seems I have no issues up to 33Vdc at the moment and I'll be careful to keep it that way.

    I spoke with the Quick Charge company today and have some info.

    Their units are not PF corrected. I made him repeat himself several times when I asked him to verify the unit would produce in excess of 1200W using only 11A 117Vac. According to them it will indeed with a voltage tolerance of +/- 3Vac.

    Frequency tolerance within reason, he said, did not matter much to the operation of it. 58 to 62hz would suffice. I then told him it was an inverter generator and he said absolutely no problems there.

    He did not have the VA rating of the charger. I wonder if one could derive that through the published specs?

    The only programmable variables are the menu select functions. He did not feel that the LiIon function applied well to the lead acid variety at all. He suggested F2 "Gas & Timed Shut Off" and to stop the cycle short of a full routine if desired. Kind of hokey way to go maybe?

    There is no idle power consumption if left connected however the display would consume power if left on.

    Here is the charging curve. Gas and shut down is the profile. I figure this will be close enough to my typical routine being ~10% charge current vs bank capacity. Looks like ~3hr run time would boost the batts nicely/efficiently especially if they were below 80%.

    http://www.quickcharge.com/Images%20and%20PDF's/charge%20curves.pdf

    That's all I have. Wish I had more. Do you guys get a warm and fuzzy from any of this?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.
    SteveK wrote: »
    Their units are not PF corrected. I made him repeat himself several times when I asked him to verify the unit would produce in excess of 1200W using only 11A 117Vac. According to them it will indeed with a voltage tolerance of +/- 3Vac.
    ...
    He did not have the VA rating of the charger. I wonder if one could derive that through the published specs?
    Eff or PF = 1200 watts / (11 amps * 117 volts) = 0.93

    Really good battery chargers seen to reach around 90% efficiency.

    "Average" non-PFC corrected battery chargers are probably in the 0.6 to 0.7 PF range.

    PFC Corrected supplies are in the 0.95 or better range for Power Factor.

    I have a bit of difficult time believing their spec.

    Either it does not output 40 amps at 30 volts or it draws more than 11 amps RMS at 117 volts would be my guess.

    You might have a difficult time getting the right answer out of them. A true RMS meter would be required to at least give you the VA rating.

    The only programmable variables are the menu select functions. He did not feel that the LiIon function applied well to the lead acid variety at all. He suggested F2 "Gas & Timed Shut Off" and to stop the cycle short of a full routine if desired. Kind of hokey way to go maybe?
    http://www.quickcharge.com/Images%20and%20PDF's/charge%20curves.pdf

    That's all I have. Wish I had more. Do you guys get a warm and fuzzy from any of this?
    Hmmm... The charging curves are not what I had hoped... Basically maximum charging current until the Vset-point is reached, then tapering down current to the 10-20% cutoff point.
    [FONT=Fixedsys] Ibatt      Vbatt
    ++++++++oooooooooo Vset/Max current
           o+
          o  +
         o    +
        o      +
       o        +
      o          +
    oo            ++++ Max Batt voltage / near zero current[/FONT] @100% SOC
    
    I am not sure I understand the descending current with the ascending voltage.

    I think the Iota has a charging profile more like I graphed above (they appear to have ~0.2 volt rise between 100% current and 0% current--I think that is at 12 volts, 24 volts should be 0.4 volt output voltage rise).

    I do suspect that this gives an answer about the above "assumptions" of 1,200 watts at 93% efficiency...

    Take the curve from the PDF--2.08 volts per cell * max current of 40 amps:
    • 2.08 volts / cell * 12 cells * 40 amps = 998 watts into battery (not 1,200w)
    • 998 watts / (11 amps * 117 volts) = 0.77 overall PF*EFF rating...
    Closer to what I would expect--but still "better" PF*EFF than I would expect. Perhaps my one of my assumptions is still wrong here (not 40 amps?).

    I think they are not near the PF*EFF that we are hoping for:
    • 85% eff * 0.95 PF = 0.81 Output / input VA rating or better
    But, I am not a battery engineer--So what I "expect" may not have any footing in reality. But the numbers still do not "look right" for what you are asking for.

    This company offers a charger that does what I would like to see (PDF) (0.90% efficiency; 99 PF, 95 to 260 VAC, 45/65 Hz), --But they are limited to 10 amps for the 12/24 volt version (I think)... If they were cheap enough, perhaps 4 of them would be a solution (and offering some redundancy).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Thanks for helping me sift through this Bill, I do appreciate it. Seems a $500.00 charger that does what I want is very ellusive.

    I compared the Quick Charge specs with the TrueCharge 2 specs and found the Quick Charge to look better at a fixed frequency and input voltage....on the surface to a layman that is. TrueCharge2 specs:

    AC input voltage range Nominal: 120 Vac, 230 Vac, 240 Vac
    Full Performance: 104 – 265 Vac ±4 Vac
    Automatic derating to 80% output: 90 – 108 ±4 Vac
    Maximum AC input current:
    at 104 Vac at 230 Vac – 20%

    TC2024: 9.0 A TC2024: 5 A
    TC3024: 13.5 A TC3024: 7.5 A
    TC5024: 22.5 A TC5024: 12.5 A

    Power factor at rated load ≥0.95
    Frequency 47 – 63 Hz
    Efficiency – peak 12 Vdc units: 77% @ 120 Vac, 80% @ 230 Vac
    24 Vdc units: 85% @ 120 Vac, 87% @ 230 Va


    I dunno but it appears to be not any better than the Iota DLS series, TC2 requires 13.5A input to produce 30A output in spite of it's PF rating and 85% efficiency rating.

    Drowning in snake oil over here. I don't get a good feeling about the Quick Charge line with no access to a simple VA spec. The TC2 looks like a poor performer to my unskilled eye. The Iota is no better there.....

    Where you spoke of the rising voltage vs the falling current on the Quick Charge curve I posted, I assumed that was because of the rising internal resistance of the batts themselves....Ohms law is about as far as I go really.

    Also on the same curve they started logging up at the 80% mark, probably where I would shut the generator down to enable the panels to pick up the rest of the routine. It appeared to be producing at or near the rated current at that point. Am I wrong to interpret the 80% point on their curve as the compliance point. Is the current not the important piece of this puzzle?

    I have managed to make some wise decisions to date for my system. The Rogue performs exactly as specified....wonderful product. The Exeltech inverter is up to snuff and has been a pleasure to work with. The panels regularly outperform their ratings...big shock for these. I expect the EU2000 to be in the same category. I don't want to drop the ball here with the one component that will let me down when the lights get dim.

    Thank you for that charger link, I will investigate this option further....
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    The effective output resistance of the QuickCharge is (from the charging profile):
    • 12 cells * (2.55 volts - 2.08 volts) / (25 amps - 0 amps) = 0.2256 Ohms
    Whether there is a "real resistor" or just the result of the controller's internal electronics (feedback loop) does not matter too much (a real resistor wastes heat/energy, feedback control does not)... But this is, IMHO, a step backwards.

    As a comparison--any descent sized battery bank you are looking at is probably going to have a resistance in the milli-Ohm range (0.00x Ohm). So the charging curve is a design choice by the manufacturer (from what I see).

    Normally, a battery charger (as I would expect) should be in current limit mode (i.e., 30 amp current regulator) until the battery voltage rises enough to hit the voltage set point--at that time, the battery charger becomes a constant voltage regulator. When the current falls to XX% of rated current, then the charger turns off / goes to lower voltage float mode charging.

    Regarding the Xantrex TC2 charger--I think the ratings are correct, but at 90 VDC (using nominal ratings):
    • 13.5 amps * 104 volts * 0.85 eff * 0.95 PF / (28.8 volts charging) = 39.4 amps
    • 13.5 amps * (104-4 min rated input AC) volts * 0.85 eff * 0.95 PF / (31+0.675 volts charging Lead Cadmium + cold offset) = 34.4 amps estimated output current
    So--if we look at the input voltage extreme, the 13.5 amps looks reasonable for a 30 amp regulator at extreme low input voltage and maximum charging voltage*rated current...

    For a 117 volt input and 28.8 volts at 30 amps:
    • 28.8 volts charging * 30 amps * 1/0.85 eff * 1/0.95 PF * 1/117 volts = 9.1 amps
    VA rating should be:
    • 13.5 amps * 100 volts = 1,350 VA (+/-?)
    The "load factor" or Watt output / VA = 0.85 * 0.95 = 0.81 or 1/0.81 = 1.24 ...

    So, I think the TC2 does what you need, at the input current you would like (for a Honda eu2000i) and the output voltage has several ways you can adjust (choose Lead Calcium for 31 volt charge, or choose "cold battery" for +0.675 output voltage increase) or even (per PDF Manual):
    2.The charger can be programmed with custom charge setpoints using PC interface. This programming can only be done using a special configuration tool operated by Xantrex or a designated OEM.
    The only thing that paying more money may get you is 0.90 eff * 0.99 PF = 0.89 load factor (or 1/0.89 = 1.12)... How much would cutting 117 volt input current/fuel usage by 12% vs the hours saved with the TC2 (or other constant current/constant voltage 30-40 amp charger) be worth?

    The only thing missing from the TC2 (that I can see) is the the programmable AC input current limit (like can be done with some of the Inverter/Chargers) and the ability to program exact charging profiles in the field (must be by OEM/Factory).

    At least, as far as I can tell, the TC2 specifications are self consistent (at least to within a 10% or so range--I am guessing 30 amp output at 31.675 volts--that may not be true).

    Could you run into some issue between the Honda eu2000i and the TC2 24v*30 amp charger--possibly--I just don't know. Unfortunately, you need to either test the setup yourself or find somebody that has done this setup successfully.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Question about battery charger selection with EU2000 generator.

    I should add, I don't know that the TC2 24 chargers are yet available...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SteveK
    SteveK Solar Expert Posts: 387 ✭✭
    Re: Question about battery charger selection with EU2000 generator.

    Clarification was excellent Bill, Tx again.

    Well the Truecharge2 would work well enough....one hitch, they do not exist.:-) Xantrex moved all 24V chargers to the XC line they don't look all that great.

    Well back to square one...

    Maybe a simple variac is in the cards for me. Joking of course.