Battery vs genny questions

johnm1 wrote:
Oh ... I'm sure there's fun to be had by all ... as long as the beer is cold and we don't run out!

Back to the converter question please ...

Do I "need" a 75A converter even if I end up adding a 2nd battery or is a smaller (lower) power one OK?

Two group 24 deep-cycle batteries (not yours) would be best mated with a 30 to 45 amp 3-stage charger. Otherwise; the charger will sense a smaller battery and never go into "bulk charging" mode.

The idiot hired by your manufacturer knew little about charging systems. I suspect the cabling used is nowhere near a heavy enough gauge for proper operation. In this case "bigger is NOT better" when taking into account; charger capability, battery-bank size, and required cable gauge size for proper operation.

Oh ... I'm sure there's fun to be had by all ... as long as the beer is cold and we don't run out!

Back to the converter question please ...

Do I "need" a 75A converter even if I end up adding a 2nd battery or is a smaller (lower) power one OK?

Without investing some $$$ into this venture I'm afraid your genny will have to run many hours daily increasing in runtime as the days go by. A second battery ($90), upgrading WFCO converter ($200), converting to LED lighting ($50-150), and/or purchasing a portable 40 amp smart charger ($125) can all play a part in effectively reducing generator runtime.

Camping off the grid for extended periods shouldn't be taken lightly as it could significantly diminish the quality of the camping experience. Additionally you may find that you enjoy this type of camping (you already have a genny) and further investment will yield improved results when doing so. We prefer this style of camping and our first step was to add a second battery (there's always room somewhere for it) which gave us more time between charging cycles via genny. Sounds like a great trip ahead, here's hoping it all works out and everyone has a wonderful time.

With only a dual purpose group 24 battery, you will find that you will need a lot more generator time than you think you will need. The manufacturer should have installed a true deep-cycle battery in Group 27 (unless not possible).

Sorry to downplay chance of success, but that battery cannot survive without plenty of generator time. The WFCO 9875 would, in theory, supply up to 75 amps but not possible with one crappy small dual-purpose battery. The converter/charger will most likely not come close to too full capacity. That size charger should be mated with more than two batteries.

Amp outlook may only be about 15 amps per hour of generator time.

The best way to find out who is giving you an honest answer here is to do a 24-hour test at home, or a weekend at a campground where you can plug into shore-power when things go south on testing.

I think I'm starting to get a better understanding here - thank you.

So it looks like the wimpy dealer installed battery isn't as up to the task as I had hoped. I do have a good quality battery charger that I can bring along to use.

If I did want to upgrade/replace the WFCO 9875 converter, do I need to stay with the 75A unit size or is smaller OK? For the life of me I can't figure out why I'd need 75A of 12Vdc power for the camper.

Solar is out of the question - way too many trees in NYS to get good sunlight - even dappled sunlight is tough sometimes.

Adding more bat's in series (as in 2 x 6V) or parallel ... there just isn't enough room without some pretty significant changes that I'm not willing to make right now.

To respond to BFL13 - the genny isn't that much more noisy than the Honda units.
- Honda EU2000i is 53 - 59 dBA @ 9 feet
- Champion 2000 Watt Inverter (73531i) is 53 dBA at 23 ft. On "Eco" mode, it's very quite.

Thanks,
John

That model gen is noisy and you will need to run it most of every day but the park won't allow it. You just "can't get there from here"

You need more battery, and a higher amp charger to just get by. "Some solar" won't do you much good either since you would need lots to make any difference.

It is going to cost money to prepare properly for this trip. Who are these tent campers anyway? If it is a group that you will be doing this with every year perhaps you can pass the hat so they can all chip in and the "group" can own the "extra" things needed. But then somebody has to maintain the extra batteries for the rest of the year on a trickle charger.

Whatever it is all about, more preparation is needed to make this an enjoyable event, which it can be of course. RVing is good for you! :)

Congratulations on starting off thinking effectively. I did a lot of boat work before the depression and I can tell you that very few people look into their energy requirements as carefully as you have.

In you case, the only battery number that matters is RC (Reserve Charge). This is the number of minutes that the battery can deliver 25amps until it reaches 10.5V (where most cars will never start).

The 100 tells you that the batteries absolute capacity is about 40 Amp-Hours (25A*100m/60m/hr) at headlight load. I suspect the at you loads it will be closer to 60AHs, but going to 10.5V will permanently damage the battery. Best to stop a 12.0. That gives you about 30AH to work with.

By your own calculation you will be very close to using that every day. But, the less the battery is depleted, the more readily it can be recovered.

Problem:
Charging lead/acid batteries takes time. That cannot gotten around. It turnout out that you can recharge to 90% relatively fast, but that last 10% can take hours. Just because you WFCO can put it out does not mean that the battery will accept it.

Without expensive instrumentation, the best you can do is get a good digital meter that you can use to track the battery voltage. I am certain that the best you will could do would be to plan running your generator for about four hours a day (give or take) divided into morning and evening as best fits your schedule. I suggest that you start as early in the morning as your group will allow and as late in the evening - the same. You can adjust this as you learn.

If you pack a long extension cord so you can move the generator away from all the campers, everybody will appreciate that.

Most people are not very good at managing without the grid for long periods. So, be ready to make a few friends of those that need iPhads charged. Maybe you should pack a plug strip just for them.

Matt

A G24 battery has app 40 usable AH to a 50% state of charge. Don't let the battery go below 12.00 volts before recharging it.
Did you measure your WFCO bulk voltage? WFCO's aren't known for going into bulk mode easily. Yes, a separate 40A battery charger would be better.
My guess - you'll be running the genny 3 hours every other day (at the least.)
NYS park? I believe genny hours are 9-11AM and 4-7PM.

Bring a 40 amp battery charger, your WFCO won't get the job done when all it wants to do is absorption charge at 13.7V, when the batteries, when dry camping need 14.4 to 14.7V to fully charge.

You have a 75 amp battery. Since you shouldn't run those batteries below 50%, 37 amps is all you get out of your batteries before you should shut things down, and it's better to recharge them long before they get to 50% discharged.


Best bet is to pull your car in, attach the jumper cables to the battery in your car, then start your car up and let it idle for a half hour to hour or so, every morning.

Or buy a Progressive Dynamics PD9245 Charge Wizard, with the pendant, so you can activate the charge controller to charge in bulk mode at 14.4v and top your batteries up, which is plenty for a single battery.
Do a search here under PD9245 for more detailed information, these charge controllers with a pendant have a great track record for dry camping and getting batteries charged up... the WFCO, not so much, with it's inability to get into bulk mode. It's a charge controller more designed for campgrounds with full hook ups, so it doesn't boil your battery cells dry while hooked up to a pedestal 24/7 for a couple of weeks.


Here was my observation with a single group 24 and a WFCO 8960. I basically had to run my Honda 2000 3 hours first thing in the morning, and 2 hours every evening, while the lights were on, to keep any sort of charge in the battery, the WFCO 8960 was miserable at topping up a single group 24 DC. I basically had to shower with the generator running, and try to do some of my TV at night with the generator running, even though I had an inverter to run the TV off the battery, plus in the morning to get some news, and charge the cell phone battery, as well as laptop.

BTW, since going to a industrial sweeper type battery and solar panels, I have a very lightly used PD 9245 with pendant for sale. PM me if this interests you.