Honda generator big enough?

Will2020
Will2020 Solar Expert Posts: 62 ✭✭✭✭
I have a Carrier air v, air conditioner on my rv, which is rated at 13,500 btu.

I found a great deal on a Honda EN2500 generator. It's rated at 2300 watts.

Would this be big enough to push the a/c? or do I need to get the Honda EU3000?

Thanks.
«1

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?

    Alone? Or in conjunction with other loads?
    If you can't get a Watt reading on the AC unit (via Kill-A-Watt by preference) remember that one standard AC outlet is 15 Amps @ 120 Volts = 1800 Watts. If that's all you're running off the gen, it should handle it (non eco-throttle type; the little eco ones tend to choke and quit if hit with a big surge load like motor start-up).
  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    I plan on running the a/c alone from the generator and the rest off od dc.

    Will a Honda EU2000 push it? I don't think it is rated for 1800 continuos watts. Could it handle the surge?

    My a/c does not have a plug to go into a killawatt. It runs off of the 30 amp plug.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?

    The EU2000 is only rated for 1600 Watts. Not likely it would stand the AC unit, or at least not for long.

    This has a 30 Amp, 240 VAC plug on it? Are you sure it's not a 240 VAC unit? Got to get a check on the electrical specifications to be sure you're able to supply the right Voltage and Amperage. It must be written down somewhere.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Honda generator big enough?

    From what little I have seen--a 30 amp 120 VAC plug is common to RV's and RV camps (run an A/C unit plus some other 120 VAC loads).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?
    BB. wrote: »
    From what little I have seen--a 30 amp 120 VAC plug is common to RV's and RV camps (run an A/C unit plus some other 120 VAC loads).

    -Bill

    So the unit is hard-wired to the RV, and there's only the "shore power"/generator input available for the whole rig? Sounds like the need to prep for full load: 3600 Watts.
  • PhilS
    PhilS Solar Expert Posts: 370 ✭✭✭
    Re: Honda generator big enough?

    You can use the Kill-a-watt through the plug for your RV, with an adapter or two. It WILL make a big difference whether or not other things (like your 12V charging system or the fridge) are operating too.

    The Honda eu2000i isn't enough to get an RV air conditioner started but it will keep it running once started. I base this on a camping trip a few years ago where another camper was using one Honda eu2000i and one Honda eu1000i together.

    I observed the setup in operation. Both running together would start the A/C with no problem. He'd set the thermostat as low as it'd go so the A/C wouldn't cycle, then he could shut the 1000 off and the 2000 would keep the A/C going. He learned this from having the 1000 run out of gas but everything kept going fine on the 2000 until the A/C cycled.

    I'd wondered for a long time whether a 1000 and a 2000 could be tied together (we ARE talking the 'inverter' models here only). He'd wondered too, and when he couldn't find a definitive answer, bought a 2000 and made a connection cable to try it (he already had the 1000).

    Two 2000s will start and run the A/C with no problem, of course. And his "experiment" proved that a 2000 and a 1000 will work together and also start the A/C.

    He had learned a specific procedure for starting them that I don't remember (one before the other made a difference on which one 'synced' to the other). I have the 1000 and was very interested because of those rare times we'd like air conditioning, but I haven't bought a 2000 yet. He needed to start one before the other (can't remember which) and they had to have the ECO 'off'. Then it was no big deal.

    So depending on what you may have already ... IMO two 2000 units are better than the 3000w Honda because the two are easier to lift individually than the 3000 and much of the time you can just use one 2000 when you don't need A/C. I'd opted to get a 1000 so that DW wouldn't have any problems lifting it and starting it. Someday I'll probably get a 2000 so we can be cool on the very hot days.

    None of this applies if you use the EN series Honda. It can only be done with the inverter models.

    Phil
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?

    Hmm. I've got both gens and a few old AC units laying around ... might experiment with that this Summer - assuming schedules ever allow me to get back to the cabin.

    I'd bet it would work if you start the 2000 first, then add the 1000. Probably help to have some small resistance load on too. Although continued use (or one mistake) will probably shorten the gens' lifespan.
  • PhilS
    PhilS Solar Expert Posts: 370 ✭✭✭
    Re: Honda generator big enough?
    Hmm. I've got both gens and a few old AC units laying around ... might experiment with that this Summer - assuming schedules ever allow me to get back to the cabin.

    I'd bet it would work if you start the 2000 first, then add the 1000. Probably help to have some small resistance load on too. Although continued use (or one mistake) will probably shorten the gens' lifespan.

    Yeah, Coot, IIRC he did need to start the 2000 before the 1000, so that the 1000 would 'sync' to the larger generator. Then not having the 1000 on made no difference. Doing it the other way caused a hiccup when the 1000 was shut down and the 2000 was 'synced' to it.

    All things considered, it really wasn't any big deal.

    He also made his own cable to tie the two together rather than spend the big bucks Honda wants. The benefit of the Honda cable is that it uses shielded banana plugs. His uses standard plugs. So IF his gens were running AND one plug got accidentally pulled out AND someone were to put a body part across the hot prong and either of the other two they COULD get shocked, burned or killed.

    Not so with the Honda harness. For the huge dollar difference and the remote possibility of danger, he chose to do it the cheaper way. I would do the same thing. I can't recommend anyone else do that, of course.

    Phil
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: Honda generator big enough?

    A 13.5 KBTU A/C is fairly large. On my very limited experience modern smallish A/C units seem to run at about one amp of 120 V AC CURRENT per KBTU. And, of course starting is the hard part.

    I would be surprised if the EN2500 would start it. Think that it would be too much for an EU 2000 to start as well. I would GUESS that the EU 3000 would start the 13.5 KBTU unit, unless it was at a very high alltitude, or perhaps very hot ambient temps.

    Just guesses. My Eu 2000 will start the lil 6000 BTU window A/C ... OH, that was NOT the question.

    Many RVers seem to use the EU 3000 with their A/Cs. Someone here must have direct experience.

    Would be cautious using the KillaWatt, for fear of hurting it with excessive current.

    Good Luck, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    I think a 3000 would be my safest bet.

    I'm looking into the older EM and EB Honda 3000 generators with cycloconverter technology. (Because I can get one sooo much cheaper)

    Is this type of generator more reliable than the standard generator head variety?

    Has anyone had any problems with theirs?

    The EU series has the same cycloconverter technology if I am not mistaken, or is there a difference?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?

    It is my understanding (and I could be wrong) that this is not the same technology. The EU inverter gens use a DC base which is ramped up to the required output, allowing for the eco throttle (change in engine RPM results in change of frequency for most generators - the inverter technology eliminates this). The cycloconverter allows higher power from a compact unit by converting 3 phase power to single phase output. The generator runs at a constant speed. I see no reason why this should be less dependable than any other solid-state control unit, which is pretty dependable.

    My Honda EU1000i has about 6000 hours on it and has yet to be rebuilt. Yes, it uses oil. But it still starts and puts out nearly full power. (I don't get "full" full power at 3000+ feet anyway.) The EU2000i isn't anyplace near that number of hours. Yet. :D
  • Shadowcatcher
    Shadowcatcher Solar Expert Posts: 228 ✭✭✭
    Re: Honda generator big enough?

    If the AC units do not already have one installed a hard start capacitor will help.
  • techntrek
    techntrek Solar Expert Posts: 1,372 ✭✭✭
    Re: Honda generator big enough?

    It also depends on how new the A/C is. Newer units use the newer gasses/pumps and tend to be more efficient as a result. Mine is 2 years old and only uses 1000 watts running (fan set on low). My old camper was closer to 1600 watts. Usually the 2000 watt inverter-gensets do not start camper A/Cs, but that was the rule of thumb with the older units, the newer ones often will with the hard-start capacitor kit (about $12 on ebay).

    The biggest issue on my camper isn't the A/C, its the converter. It has such a large surge when it is first plugged in I would probably have to plug/unplug several times before the internal capacitors are charged. I haven't tried to run it from a genset but I have tried from my 6 kw inverter and it tripped several times before I got it going - that inverter doesn't trip when I run my 1800 watt chainsaw from it, which has a serious surge!
    4.5 kw APC UPS powered by a Prius, 12 kw Generac, Honda EU3000is
  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: Honda generator big enough?

    I don't have a camper, but do have two 9000 BTU 120V AC units - one is a mini-split in my "server room" closet, the other is a portable AC unit. My EU2000i can't start the mini-split, it just bogs way down and nothing happens with the AC. But it'll fire up the portable unit without even lugging / surging - just raises the idle a bit! Sure surprised me...
  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    I'm considering buying this Honda EB3000c cycloconverter generator, but I can not find any info on how many rpms it turns. I'm assuming that it is the standard 3600 rpm constant........

    Does the Honda EU series run at a continuos 3600 rpms? Or is it variable?

    I want one that will give me the longest engine life, and I assume that a slower turning generator will last longer.

    Any thoughts?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?

    The smaller "inverter" gens like the EU2000i have an "eco-throttle" mode which allows them to slow way down when power demands are light. This can also be shut off for constant RPM operation, as you would do if trying to start any heavy loads (the eco-throttle doesn't respond fast enough sometimes).

    As far as I know, the EB3000c is a constant RPM design, in all likelihood turning 3600 as you suspect.

    Not like the "prime power" type diesel gens that roll over at a leisurely 1800 for longer engine life.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Honda generator big enough?

    The eu1/2000i are variable RPM gensets... They have a wild frequency alternator feeding an inverter that outputs fixed voltage/frequency. They do idle back when outputting low power (and throttle set to eco-mode). They do not do well at supplying surge current when idled back... Turn of eco-mode when running loads with high starting current (A/C, well pumps, etc.)--sometimes you can eco throttle once the device as started.

    I guess they are 3,600 RPM at full power...

    Wayne from Nova Scotia has somewhere near 6,000 hours on a Honda eu1000i (with good maintenance)--But I probably would plan on 1-2,000 hours before replacement.

    The engine used in the 1000/2000 is usually not worth repairing (and you would probably not be successful anyway sealing it back up from what I have read).

    An 1,800 RPM with pressurized oil and filter is probably going to give you a longer life.... But finding one of those in the 1,500 watt size is probably close to impossible.

    And if you do get a 5-10kW and run it at 1,600 watts or less--it will probably drink the fuel like no tomorrow.

    I really like conservation and small loads driven by small gensets... But finding a good prime rated genset that small appears to not be possible. So--you are left with trading fuel costs/replacement against longevity.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    Heres another one.

    Right now I have an Iota 30 amp converter, and it charges my 315 ah worth of batteries extremely slow.

    I charged them at 14.1 volts for 1 1/2 hours the other day, and it filled my batts up 5%.


    Assuming the 30% factor, I can use a 90 amp converter, but they are too expensive and I'm thinking of uprading the Iota to 55 amp.

    Would it be possible to run the 55 amp charger and my 13.5 amp a/c at the same time with the Honda EB3000c?

    It is rated for 3000 watts max with 25 amps, and 2600 running with 21.7 amps.

    Will the generator even push the 30 amp converter, if it is only rated for 25 amps max? I'm confused.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Honda generator big enough?

    Here is a good thread that goes into the details finding a good/efficient charger for a small genset:

    Question about battery charger selection with EU2000 generator.

    Your Iota should charge about 10% points every hour until your battery is around 80-90% full, then it can charge slower (bulk vs absorb).

    I would look for a charger that can output closer to 14.5 to 14.8 volts (or even more)--It will be a little bit "harder" on the battery bank, but it will charge your batteries much faster and make the genset more fuel efficient. 14.2 volts (Iota published specification) is a fairly gentle charging rate and probably not ideal for use with gensets on a regular basis (especially if you are looking to charge above ~80-90% state of charge where a higher voltage will help with quick charging).

    Depending on the charger--A simple non-pfc (power factor corrected charger) would probably run on a 2,600 watt continuous load genset:
    • 2,600 watts * 0.6 PF * 0.80 charger efficiency * 1/14.5 volts = 86 amps
    A PFC Corrected power supply with a better battery charger can do better:
    • 2,600 watts * 0.95 PF * 0.90 * 1/14.5 volts = 153 amps
    But--believe it or not, finding the optimum battery charger for use on a genset is actually quite difficult.

    Of course, if your charger is set for relatively low voltage (like 14.1 volts), it will slow the current flow down once the battery is ~80-90% full... So even a larger charger, by itself, will not solve the long run-time/high fuel usage issue.

    Stevek's thread above went into the gory details about selecting the optimum battery charger for a small genset.

    Take a look at it and see if it helps answer some of your questions.

    I don't know if the Iota can be tweaked or not.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Honda generator big enough?

    the Honda EB3000c cycloconverter is a fixed speed generator, that downconverts higher frequency AC, to 60 hz

    http://www.hondapowerequipment.com/products/generators/content.aspx?asset=gg_cycloconverter
    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 ,

  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    Well, I have never drained my batteries past 83 %, so this may be why it charges at a slower rate.

    I am only running led lights, a 1 amp fan, and the dc/propane fridge. I don't see any reason why I should go over 10-15 amps per night.

    I don't understand how a 30 amp converter can be used with a 25 amp max generator. Is there a hidden formula for this?

    Is it actually drawing 30 amps from the source continuosly?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Honda generator big enough?
    Will2020 wrote: »
    I don't understand how a 30 amp converter can be used with a 25 amp max generator. Is there a hidden formula for this?

    Input or output, that is the question.

    The generator puts out 25 Amps @ 120 VAC = 3000 Watts
    The converter puts out 30 Amps @ 12 VDC = 360 Watts (426 Watts @ 14.2 VDC)

    If that's where the numbers come from (generally battery chargers' Amperage rating is on the output side, not the AC input).
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Honda generator big enough?

    The inverter is outputting 30 amps at 14.1 volts:
    • 30 amps * 14.1 volts = 423 Watts
    The generator is outputting its energy at ~120 Volts AC... The common power supplies have some sort of step down transformer (or other inductive methods) to efficiently output the ~14.1 volts DC you need to charge your battery bank.

    The current from the genset is based on 120 VAC--Ignoring a whole bunch of other factors, the ideal current from your genset to generate 30 amps @ 14.1 volts:
    • 423 Watts * 1/120 VAC = 3.5 amps of 120 VAC current from genset
    In real life for most power supplies that is actually closer to ~7 amps at 120 VAC...

    A transformer is sort of like the transmission on a car... In low gear, the engine turns very fast but the wheels turn slowly--but with lots of torque. That is what the "power supply" transformer does for you--Match the high voltage/low current from the genset and down converting it to the low voltage/high current needed by the batteries (and doing it efficiently).

    http://en.wikipedia.org/wiki/Transformer

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Honda generator big enough?

    "A transformer is sort of like the transmission on a car... In low gear, the engine turns very fast but the wheels turn slowly--but with lots of torque."

    that's a great analogy bill.
  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?

    I went ahead and ordered the EB3000c to run my 13,500 btu a/c.

    According to Carrier, the surge is 2700 watts.

    If I installed a hard start capacitor, would that extend my generator life by taking some of the surge load off of it?

    What is a good brand of capacitors? Coleman? Dometic? Supco?

    Are there certain specs that I am looking for?

    Thanks.
  • dwh
    dwh Solar Expert Posts: 1,341 ✭✭✭
    Re: Honda generator big enough?
    BB. wrote: »
    I guess they are 3,600 RPM at full power...

    I think most of the small inverter gens run between 4,000 and 5,000 rpm with eco off.
  • 2manytoyz
    2manytoyz Solar Expert Posts: 373 ✭✭✭
    Re: Honda generator big enough?

    This topic is often discussed on the RV forums.

    From many posts by EU2000 owners, this generator is too small to reliably restart the A/C unit once it has some head pressure on the compressor. "Most" EU2000 can't even intially start a 13,500 BTU A/C unit.

    The fix in their case is to buy another EU2000, and bridge them together. This will run a 13,500 BTU A/C reliable. But that's twice the cost, plus the cost of the box to bridge the two. Also doesn't share the load equally. Often reported one generator running near full throttle, one loping along. Honda says this is NORMAL, nothing to worry about. They do share the load, but they don't share it equally. Not a issue, but rather a quirk.

    I went for the Yamaha EF2400iS. It was designed for running a 13,500 BTU A/C unit, solo. It can be bridged with another like generator, but not necessary.

    As for the startup current, you won't see it on the average meter, and certainly not on the very useful Kill-A-Watt. These are too slow to capture the spike.

    I've since invested in a Fluke meter that captures In-Rush current. Has a very fast data acquistion rate, compare to most meters that claim to capture peak current. Consequently, get a more accurate reading.

    Here's what my Dometic 13,500 BTU A/C unit draws at startup, then running current:

    rvaccurrent.jpg

    rvacrunning.jpg

    The issue is nowhere in the literature will you find what peak current a generator can supply.

    Furthermore, my generator easily starts, runs, and restarts the A/C compressor, but it won't start my air compressor.

    aircompressoramps.jpg

    The Dewlat Emglo air compressor has a 1.8HP motor. It's just a tad too big for the generator to start. It will try for ten seconds, slowly turning the compressor, before the generator indicates overload. Only a few Amps more than my A/C unit, but that made the difference.

    The new version of the EF2400iS generator has the ability to start things the old generator couldn't, but lacks the ability to be bridged with another generator.

    An interesting tidbit of the EF2400iS is that it uses the same sized motor as the 2800, and 3000 Watt Yamaha generators, yet is 1/2 the weight of the Honda or Yamaha 3000W generators. Since I want my generator mobile, that was the selling point for me over the others.

    Details of the testing I've done with my generator at this link:

    http://www.2manytoyz.com/yamaha2400.html

    FWIW, the Yamaha generator doesn't have an eco-throttle that can be bypassed. It runs only as fast as needed. When I turn on the A/C, the generator increases RPMs as needed, and there's no hesitation of the A/C starting. I attribute that partially due to having the larger motor (doesn't bog down). Same when I operate an electric chainsaw. Motor RPMs ramp up, but chainsaw is at full speed almost instantaneously. Just as if I was using grid power.
  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Honda generator big enough?

    Here is a interesting item, Dometic Smart Start. I was going to get one to test, but at $400, I passed. That doesn't mean that it might not solve a problem and be quite a bargain.

    Quick start" kit (Part # 3102903.006)

    http://www.youtube.com/watch?v=iEu5clbUbts

    Analysis
    The Honda EU2000i is quite a potent little device. Regardless of the start component configuration, it was able to start the 16000 BTU system reliably when the ECO mode was turned off. When the ECO mode was turned on, however, the generator had trouble with the standard configuration and with the Supco SPP6E installed. The Supco Super Boost did help, but the resulting voltage drop to around 67V (46%) was problematic in that it did sometimes reset the digital controls. Other equipment running off the same generator would have also been affected.

    The SmartStart made a dramatic difference. With the ECO switch turned on, the generator was able to tolerate the 18 amp start surge with only about a 20% drop in voltage. With the ECO switch turned off, the generator didn’t even flinch (i.e. no measurable voltage drop).

    Summary
    As was cited elsewhere in this thread, the Honda EU2000i can support a 16,000 BTU air conditioner without any added hardware. But as our testing showed, this would only work if the ECO mode was turned off. Adding the Supco SPP6E provides a marginal improvement, but for our specific test with the 16000 BTU system, it could not guarantee a reliable start-up if the generator was operating in ECO mode. Beyond this, if other equipment is already loading the generator (e.g. sea water pump), that will further reduce the available amperage for the compressor start-up. Adding the Dometic SmartStart provides a dramatic improvement, provides a reliable start under almost all conditions, and will allow the generator to be run in ECO mode, which will certainly reduce fuel consumption.


    I don't know anything about this item, I found it on a Google search.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Honda generator big enough?
    2manytoyz wrote: »
    ...
    Details of the testing I've done with my generator at this link:

    http://www.2manytoyz.com/yamaha2400.html

    FWIW, the Yamaha generator doesn't have an eco-throttle that can be bypassed. It runs only as fast as needed. When I turn on the A/C, the generator increases RPMs as needed, and there's no hesitation of the A/C starting. I attribute that partially due to having the larger motor (doesn't bog down). Same when I operate an electric chainsaw. Motor RPMs ramp up, but chainsaw is at full speed almost instantaneously. Just as if I was using grid power.

    Darn, too bad it's not 240V, or I'd snag one in a minute as a backup.

    I suppose I could get a transformer and boost it up......
    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 ,

  • Will2020
    Will2020 Solar Expert Posts: 62 ✭✭✭✭
    Re: Honda generator big enough?
    BB. wrote: »
    Here is a good thread that goes into the details finding a good/efficient charger for a small genset:

    Question about battery charger selection with EU2000 generator.

    Your Iota should charge about 10% points every hour until your battery is around 80-90% full, then it can charge slower (bulk vs absorb).

    I would look for a charger that can output closer to 14.5 to 14.8 volts (or even more)--It will be a little bit "harder" on the battery bank, but it will charge your batteries much faster and make the genset more fuel efficient. 14.2 volts (Iota published specification) is a fairly gentle charging rate and probably not ideal for use with gensets on a regular basis (especially if you are looking to charge above ~80-90% state of charge where a higher voltage will help with quick charging).

    Depending on the charger--A simple non-pfc (power factor corrected charger) would probably run on a 2,600 watt continuous load genset:
    • 2,600 watts * 0.6 PF * 0.80 charger efficiency * 1/14.5 volts = 86 amps
    A PFC Corrected power supply with a better battery charger can do better:
    • 2,600 watts * 0.95 PF * 0.90 * 1/14.5 volts = 153 amps
    But--believe it or not, finding the optimum battery charger for use on a genset is actually quite difficult.

    Of course, if your charger is set for relatively low voltage (like 14.1 volts), it will slow the current flow down once the battery is ~80-90% full... So even a larger charger, by itself, will not solve the long run-time/high fuel usage issue.

    Stevek's thread above went into the gory details about selecting the optimum battery charger for a small genset.

    Take a look at it and see if it helps answer some of your questions.

    I don't know if the Iota can be tweaked or not.

    -Bill

    I drained my batteries down to 69% and 12.5 volts.

    I put the Iota 30 on them for an hour at at a 14.2 volt charge rate.

    My numbers are now 78% and 13.3 volts.

    It charged 27 amps in one hour. Is this feasable for a generator setup, or does it need to be faster? It is pretty close to the 10% mark.


    I was looking into the Xantrex truecharge 40 amp. What is the charge rate on these? I could not find that specification anywhere.

    How much faster would it be if I used the power factor corrected Xantrex? Assuming I am below 80%

    Thanks