Charging batteries with Honda eu2000i

YostFMX
YostFMX Solar Expert Posts: 94 ✭✭✭
How does everyone charge their battery banks (for backup) with the Honda eu2000i generators? The battery charge cables that Honda sells for the generator is pretty much meant for charging only one battery. How do you charge your bank with out letting it run for days? I know theres got to be something I'm missing?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    Yep; you're missing the battery charger.

    The 12 Volt output from these little gens is inadequate for charging most banks as it is only 8 Amps. The 120 VAC output on the other hand can run quite a sizable battery charger.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    The Honda EU 2000 will power a IOTA 75 AMP charger without a issue. With a IOTA 55 AMP it will run with the ECO throttle on and pretty much lope along. I have seen on a couple Boating forums that it will pull a 90 Amp maxed out, no confirmation though.

    I have a 55 AMP and am pretty happy with it. Remember as the RPM goes up so does the sound and Fuel consumption. It'll pull about 9-10 amps AC generator at full output.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    Re: Charging batteries with Honda eu2000i

    If you are interested in the details of the the "simple" question you asked--here is a good thread:

    Question about battery charger selection with EU2000 generator.


    Unfortinatually, the details of AC battery charging mean that many "simple/inexpensive/heavy duty" battery chargers have very poor "Power Factor" which can reduce the apparent generator capacity to 60% or even 50% of name plate rating (the AC Voltage Wave form is a "sine wave"... For many/most AC battery chargers, the current wave form is a a series of current spikes at the peak of the voltage wave form--This causes I2R heating (2x current causes 4x heating losses) of wiring and transformers (and circulating current in transformers--more heating/losses). "Good Power Factor" is around 0.95 to 1.00 or 95% to 100% of rated generator capacity (there are other losses too).

    For example, a 1,600 watt Honda eu2000i, the different available battery chargers can output a maximum of:
    • 1,600 watt * 0.6 PF * 0.80 Efficient charger * 1/14.5 volts = 53 amps maximum @ 12 volts
    • 1,600 watt * 1.0 PF * 0.80 Efficient charger * 1/14.5 volts = 88 amps maximum @ 12 volts
    • 1,600 watt * 1.0 PF * 0.90 Efficient charger * 1/14.5 volts = 99 amps maximum @ 12 volts

    Note that, roughly, a generator will be name plate rated in VA (i.e., not including power factor)--But fuel usage (gallons per hour) will be based on Watts (i.e., 53 amp output power supply will use less gallons per hour of fuel than a 99 amp Power Factor Corrected power supply).

    I am a big believer in matching Generator Capacity to Charging (+AC load) capacity... A genset, in general, is fairly fuel efficient from ~50% to 100% of rated load (Watts). For "standard" gensets, their fuel consumption (gallons per hour) does not drop much for loads from 50% to 0% of rated load.

    The Honda, Yamaha, and other Inverter-Generators tend to be more fuel efficient a lighter loads, if "ECO Throttle" is turned on (allows engines to slow down RPM for light loads).

    If you have the interest, we can go further into the details if you wish ("poor power factor" is a pretty big issue for off-grid solar/generator power).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    I also have an Iota for 12V charging - can't remember if it's 45A or 55A, but of course runs fine on the Honda.

    For my 48V Outback system I simply connect the generator to the FX inverter and tell the system to charge. I have the FX's Max Amps setting adjusted down to match what the generator can do.

    I don't think I've ever used the 12V output on the generator!
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Charging batteries with Honda eu2000i

    An Eu1000 will easily drive a Xantrex TC 20 into 12 vdc. The PF of the charge is ~ 60 if I remember. As Eric (Westbranch) points out, he is able to run the TC 40 on an EU 1000 once it gets out of the very first bulk charge phase. I could not get TC 40 to run on the 1000, but it would certainly run on a Eu2000. With the TC 20, the Eu1000 just idles along.

    Tony
  • YostFMX
    YostFMX Solar Expert Posts: 94 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    Wow these chargers are sorta pricy. I think I'll stick to my 12v 8A DC plug on my generator, not enough days in the desert with out sun to justify it. So I (ever) do need to charge my battery bank with my 12v outlet on the generator, could I just clamp the leads from the generator to the DC input (where the solar panels come in) on my charge controllar so I don't over charge the battery?

    I must say I thought I knew a pretty good amount about how all this solar off the grid power stuff worked/works, but then I come on here I find out I really know nothing haha.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    Don't feed a charge controller the DC output of the gen. There's no telling how well-filtered the output is and the controller may not like it.

    The Iota (and such) chargers are expensive because they have the whole complex deep cycle charging profile programmed into them. This isn't actually necessary for or occasional "emergency" bulk charging: you can use the inexpensive automotive chargers available everywhere. They'll at least bring the batteries up out of the dangerously low zone, and the panels may be able to finish charging after that.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    Re: Charging batteries with Honda eu2000i

    You would be much better off buying a regular car charger or one of these "simple" Iota or Power Max chargers. The 8 amp output from the Honda is not worth the gasoline needed to run it (needs to run with ECO throttle off). For the IOTA, you would only need the IQ4 module if you where plugged into AC Grid power to cycle between 14.2 volts absorb and 13.6 float. Otherwise, set for Absorb and turn off the genset when the battery if full enough.

    8a*14v = ~112 watts with probably nearly the fuel consumption of a 700-800 watt AC battery charger.

    Fuel usage--probably somewhere around 1/8th gallon per hour to run either of the above options (at $4.00 per gallon, that is 0.50 per hour) or electrical rate wise:

    • $0.50 per hour / 0.112 kWH per hour = $4.46 per kWH when charging with Generator DC plug
    • $0.50 per hour / .700 kWH per hour = $0.71 per kWH when charging with "typical" AC battery charger
    • $120 battery charger / ($4.46-$0.71) savings in fuel = 32 hours "break even"

    So--Roughly 32 hours of runtime with a "$120" Battery Charger will break even on the cost of fuel... And charge your battery bank ~7x faster.

    I have not seen it in my manual--But others here, with their "fancy Canadian:p" manuals/models, have warnings to not run AC loads when using the DC charger (for the Honda eu2000i, at least, as I recall from earlier posts here). [per Marc, my memory was faulty--It was the eu1000i with the "use one at a time" warning. -BB]

    -Bill ;)
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • YostFMX
    YostFMX Solar Expert Posts: 94 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    I really don't even think I'll ever run 32 hours on backup. Ok so no hooking up to charge controller... Being super cheap, how would I regulate charging off the DC plug from generator to the batteries? By checking the battery voltage from time to time?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Charging batteries with Honda eu2000i
    BB. wrote: »
    I have not seen it in my manual--But others here, with their "fancy Canadian:p" manuals/models, have warnings to not run AC loads when using the DC charger (for the Honda eu2000i, at least, as I recall from earlier posts here).

    -Bill ;)

    Bill is referring to this thread: http://forum.solar-electric.com/showthread.php?7230-Honda-2000i-question
    Post # 4
    To be accurate, that is the EU1000i (with 6,000 hours of run time) not the EU2000i which does not carry the same warning.

    :D
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Charging batteries with Honda eu2000i
    YostFMX wrote: »
    I really don't even think I'll ever run 32 hours on backup. Ok so no hooking up to charge controller... Being super cheap, how would I regulate charging off the DC plug from generator to the batteries? By checking the battery voltage from time to time?

    Nothing cheaper than a meter and an eyeball. ;)
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Charging batteries with Honda eu2000i

    Iota powerfactor:
    I used a kill-a-watt meter to measure my iota: (48V 15A model) 1030w 11.9A .67 PF Batteries were low, but not pulling a full load.

    Corrected chargers will be much better.
    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 ,

  • 2manytoyz
    2manytoyz Solar Expert Posts: 373 ✭✭✭
    Re: Charging batteries with Honda eu2000i

    I have a Yamaha EF2400iS generator, and use an Iota 75A charger with it. I did some actual measurements of a worst case scenario and was surprised by the power factor inefficiency:

    http://forum.solar-electric.com/showthread.php?13816-Iota-Battery-charger&p=104477#post104477

    My generator had no issue running this the charger at the full 75A capacity, but it was at a higher AC current level than expected.

    I suspect the output of the built-in charger on the Honda is as crude as the one on the Yamaha. Here's mine:

    dscn3102.jpg

    dscn3094.jpg

    Note that the AC ripple goes away as soon as the ouput is connected to a battery. The built-in chargers are handy if you're out camping, and your battery dies in your truck. This actually happened to a friend, and he was able to recharge via the built-in (wimpy) charger. Not fast, but it does work, nothing extra to carry with you, other than the cable (included with Yamahas, extra cost for Hondas).

    An external charger plugged into the generator works far better!

    I also agree this output shouldn't be connected to anything other than a battery. The ripple isn't an issue on a battery, but might booger up sensitive electronics...