Please critique decision on batteries and charging

Don't forget temperature effect! when it is cold out, the spec charging voltage goes up. Eg, 14.6v is now 15.2v when you go from 77F to 32F.

You can beat that with a charger that is temperature compensated. Only converter at a reasonable price that has adjustable voltage is the PowerMax LK model (rebranded as "Boondocker" by Randy).

You would want that for your ice-fishing, I imagine. (The PD with CW is stuck at 14.4 regardless of temp)

https://www.boatandrvaccessories.com/products/powermax-pm3-60lk-12-volts-60-amp-power-converter-battery-charger-w-led-light

wopachop wrote:
I see this as a noise level issue. Not really a battery issue. You only boondock 3 days a year, and your trailer has a huge built in generator.

Need to decide if you will feel uncomfortable running the Onan at times because it might bother neighbors. If that is the case then bring the Ryobi. You will get a feel for how long charge times take. Worse thing you could do is ignore the built in genny. Actually want to start them every month if you have the discipline and ability. I know people who store trailers hours away so they can only cycle the generator and ACs when they go camping. Which for most is not every single month.

There is a secondary issue, although not as important. in th ewinter, I have a fishouse that I stay in for the weekend. I usually use the ryobi to power the satalite, tv, lights, and pizza oven. However, recently I have been using my deep cycles to power it in the evening to keep the noise levels down. I would now use the GC batteries in the winter at the fishouse also.

I see this as a noise level issue. Not really a battery issue. You only boondock 3 days a year, and your trailer has a huge built in generator.

Need to decide if you will feel uncomfortable running the Onan at times because it might bother neighbors. If that is the case then bring the Ryobi. You will get a feel for how long charge times take. Worse thing you could do is ignore the built in genny. Actually want to start them every month if you have the discipline and ability. I know people who store trailers hours away so they can only cycle the generator and ACs when they go camping. Which for most is not every single month.

You're buying batteries from a dealer? LOL. Go to Costco or Sam's and get the same batteries for less than $100 (with core). That way, if and when they go bad, you have some place to return them to without hesitation or questions.

Yes one pair of GC2 golf cart batteries WILL give you more Ahr capacity than two group 27.

Group 27 will give you at best 80Ahr each so a pair of group 27 gives you max of 160 Ahr. However, that 80Ahr is if you ran them 100% flat.. Which will kill the capacity in a matter of a couple cycles. Basically, you would only want to take a max of 20% out of group 27 and with two that means you get 32Ahr to work with.

The lowest rated GC2s would be 210Ahr and with GC2s you can easily extract 50% of the capacity and not harm the battery so you could easily use 105 Ahr.. GC2s can also be drawn even lower than 50%, you can extract up to 80% which is what the manufacturers use to rate the amount of charge/discharge cycles at..

Don't do that to group 27s..

And yes, I use one pair of GC2s to power my home fridge conversion, I have no issue going 24 hrs without the need of recharging. Add some solar panels and I could easily make a long weekend without the need to run a gen.

time2roll wrote:
When the battery hits 14.2-14.4 volts continue one more hour. Amps will be tapering off and it gets to be a trickle charge soon enough. This is probably a 2 to 4 hour charging period. Often people run the generator when preparing a meal so the microwave and other appliances can be run at the same time. Watch the quiet hours as you don't want to start a 2+ hour charge 20 minutes before shut off. You will find a rhythm that works for you soon enough.

Costco GC2 work great for me. RV should come with at lease 2 house batteries with a residential fridge. I would ride them hard and use them up before you spend money.

I would tend to just use the Onan. It needs the exercise.

They are giving me credit toward the GC batteries. They were gong to give me two new grop 24's

A pair of GC-2 Golf Car batteries should be around 220 AH at the 20 hour rate (Give or take about 10)
The proper charge rate is about 66 (or less) so a Progressive Dynamics 9260 (or equal) would be my choice

A 1000 model INVERTER generator **SHOULD** power one of those but you are right at the limit of it's rating.. My old Generac 1000 (A 1000 watt Traditional generator that really could crank out 1000 watts).. Had no problem with a 9180+wizard.

Another factor is depth of discharge

IF the batteries are say.. ONly down 25 perent.. They likely will NOT draw the full 60 amps so the 1000 will be right happy.

When the battery hits 14.2-14.4 volts continue one more hour. Amps will be tapering off and it gets to be a trickle charge soon enough. This is probably a 2 to 4 hour charging period. Often people run the generator when preparing a meal so the microwave and other appliances can be run at the same time. Watch the quiet hours as you don't want to start a 2+ hour charge 20 minutes before shut off. You will find a rhythm that works for you soon enough.

Costco GC2 work great for me. RV should come with at lease 2 house batteries with a residential fridge. I would ride them hard and use them up before you spend money.

I would tend to just use the Onan. It needs the exercise.

“If I were to start the onan up, how long would it take to fully charge two and or 4 golf cart batteries?”

With the Onan running it is not an issue of enough power, and that should go for the Ryobi too. Bulk charging goes quickly but the absorption phase is slow...could be two-three hours plus. In absorption the batteries slowly accept less and less. This is battery basics.

You want the higher AH 6s. Eg Trojan makes a 210 and a 225. Choose the higher AH option.

Not sure of qualities. it is more about taking proper care of them. I am very happy with my 230AH East Penn GC15s, but there are many other choices.

You do not fully recharge batteries while away on generator. You run them down to about 50% and then recharge to 80% or so (called "50-80s") it takes too long to get them to a higher SOC on gen time. Wait till you have shore power to get them to full.

If you have solar you can get them to a higher SOC before dark. In that case, do your 50-80 in the morning and let the solar do what it can the rest of the day. (you can run the solar while doing your gen/charger to get more amps--just leave the solar on all day--it will do whatever it can.

The time to recharge two or four 6s from 50% depends on your charging amps and whether you do a 50-80 or a 50-90. The 80-90 part will take an extra hour of gen time for not that much gain. Think of three hours of gen time for a 50-80 on two 6s with a 55 amp charger, eg.

You need enough generator to run a charger at higher amps. two 6s can take 80 or so amps at first and four 6s can take twice that. Some inverter gens have 150a chargers, but that takes a 3000w gen to run it at those high charging amps.

Sounds like you could sell the 2200 and take the 3100 as your portable gen or VV depending on ? You don't need both anyway.