Generator/Battery Charger Question

[Meck]

Hello,

I just finished installing a Kohler 8eoz Generator after removing a Fischer Panda unit. What a difference! The Kohler is real Genset, very very happy with it. However I am thinking now that my Zantrex True Charge 2 60amp charger might be falling short. I am charging 4 Trojan L16h batteries (around 900 amp hrs) The Kohler is wired 220v 50hrz @ 1500 rpm.

Is there any advice out there on what I should expect or how to determine if the Battery charger is in fact not keeping up with the current from the Kohler?

So much to learn and not enough time..

Cheers, Meck

[Dockhead]

Congratulations! You have a very similar unit to mine, which is an EFOZ6.5 230v. I have been very happy with mine which is dead simple, overbuilt, heavy, quiet, reliable. 1000cc three-cylinder totally mechanical Yanmar diesel with no electronics at all, running at a lazy 1500RPM. I have four years of experience with it. I think Kohler is not quite as good as Northern Lights, but they are built according to similar principles. The opposite of Fischer Panda.

I have no idea what you mean about the battery charger "keeping up" with the current from the generator. The charger will draw what it needs, provided it is available (and if not, it will blow breakers). 60 amps is quite small for 900 amp/hours of batteries, and Xantrex is the -- erm -- Fischer Panda of chargers. So if I were you, I would make a clean sweep of all the crap in your electrical system and toss out the charger as well.

You might consider a charger/inverter with power boost, which will use inverted battery power to supplement a weak shore power connection -- extremely handy. I have one of this -- a Victron -- which works fabulously when it works, but I'm not sure I can recommend it whole-heartedly as I've had trouble with it, like with every other item of Victron equipment on board. You might look at Mastervolt charger/inverters which do the same thing; I don't know personally whether they are more reliable than Victron. For a charger-only which is bulletproof, look at Newmar. For a charger which is great value for the money, and they say very reliable, look at Sterling. Stay away from the X brand!

For 900 amp/hours of batteries, you probably want about 120 to 150 amps of charger. Much more than that and you will be stressing your batteries while charging; less than that and you will need inordinately long generator runs to charge up. 60 amps is definitely too small for such a big bank.

Good luck and let us know what you do in the end.

[ranger58sb]

We have an 8EOZ genset installed.

I also have one of the spec sheets (softcopy) that applies... and it indicates the 8EOZ model is by definition 60 Hz... and the 6.5EFOZ version of the same genset is the one that does 50 Hz.

If that matters?

-Chris

[djmarchand]

Meck:

Your Kohler genset supplies 220V AC to the battery charger which converts the AC to DC and charges your batteries. That charger at the full 60 amp output (which takes a semi-discharged battery to happen) requires about 5 amps AC at 220V or about 1000 watts of your genset's total capability.

With your large 900 amphour battery bank you could install a much larger charger and thereby decrease your genset recharging running time. If you need to run the genset for other reasons (air conditioning for example) then don't bother.

David

[smac999]

yes you are wasting fuel trying to charge those batteries with such a tiny charger. you should be in the 200a+ range. for simplicy I would add a 100a charger for a 160a total. or look into inverter / chargers which will run 100-140a or so.

[poiu]

I had a trojan 900Ah battery bank and after studying the battery manuals fixed my chargers to a current limit of 120A. That was the maximum current recommended for long battery life. They would only suck that much for an hour and a bit before the current dropped so you could up your charging capacity to that level with a new or extra charger to speed the charge by maybe an hour or an hour and a half as a guess. The genset shouldn't be a bottleneck.

[Meck]

Thank you all for posting! This is exactly what i needed to hear and what I suspected..

I guess I'll go shopping, again. We are in Bocas del Toro right now enjoying the cruising lifestyle and slowly setting our boat up for sustainable living. Thanks again for the advice!

Meck

[Meck]

Another question, a couple of you mentioned adding another charger to my 60amp unit to get the total I am looking for. I was under the impression this might not work very well because the end unit would be seeing the 14 plus volts of the first charger making it less efficient in its charging ability? Not quite sure if I would just be better of with one charger or two. After a little shopping around for chargers it seems that the options dwindle after the 100amp models. Let me know what you all think.

Best,
Meck

[rw58ph]

For a quick shorter charge time I have used the several 60 amp chargers, one for each battery. The boats main battery charger, and two portable battery chargers. It does not make much difference if you use one 100+ or several. I would go with two smaller battery charges rather than one, so if one goes out, there is still one as back up.

[twinboat]

IOTA chargers are designed to run in parallel. You could get 2, 60 or 75 amp units. Most chargers will be fine when the batteries are low. When they get near 90%, one or the other will take control.

[Meck]

Thanks for all of the great advice.

[Meck]

Thanks for the info. These forums are amazing. If you get a chance would point me in the right direction regarding wiring in a second charger? I'm assuming there is no need for a second line from the genset, but not sure beyond that.

Meck

[smac999]

you would need another ac breaker and ac line from ac panel to charger. same line from genny to ac panel.