Brother told by dealer coach batteries charge 80% max

[Scubawise]

Dealer said without solar your coach batteries only charge to 80% with generator?

[EA37TS]

And how much is that dealer charging for solar?

Danger Will Robinson, Danger.

[Travelin' Texans]

And you should only believe about 20%, or much less, of what comes out of your dealers mouth.

[Lt Keefer]

You know what they say, if his mouth is moving he's probably lying.

[16ACE27]

Well the dealer is kinda right because most people will turn off their generator before the batteries are fully charged, thinking it only takes a couple of hours to charge the house batteries.

[Judge]

So have your brother educate the dealer. This is how house battery charging works in a coach.

The Converter / Charger (or in some cases an Inverter / Charger depending on the coch) is powered by 110V to create 12V to power the 12V appliances and lighting in the coach and to charge the house batteries (and in somce cases the chassis batteries). The Charger is also "smart" and changes the voltage applied to the batteries to get them to a full charge and then drops the voltage to a maintenance level.

Shore power provides 110V. The Generator provides 110V. As long as the Converter / Charger has 110V applied long enough to it from Shore Power or the Generator, the batteries will be fully charged..... and maintained.

[Bob Denman]

Wow...

My B.S. meter is twitching like a toad on a hot plate..
https://www.thorforums.com/forums/at...1&d=1617708279

[paulwadley]

Looks like the dealer is still not done dealing with you.


Paul

[nosticks]

[DavidEM]

OK, I will jump into the fray here!!

The dealer is partially right. Lead acid batteries charge fast when they are significantly depleted. At 50% SOC they can charge at 0.2C (20% of the amp hour capacity). But as they charge up to 80% and beyond it drops off. Just guessing for illustration purposes, at 80% SOC they will charge at 0.1C and at 90% at 0.5%.

So unless you run your generator all day you will not get to 100% after starting at 50%, thus the dealer's statement.

Solar is the perfect "top off" charging system as long as you are not shaded. In the morning use your generator for a few hours to get to 80% or above, then let your solar top off the last 20% over the day.

A solar system rated at 0.1 * (C*12) should work well to fully charge up the batteries during the day as long as it isn't shaded.

David

[Judge]

My Progessive Dynamics Converter will charge the batteries to 90% capacity in 8 hours or less depending on how far they were depleted and full charge in 11 hours.

If I was driving 8 hours (with the alternator charging the batteries) and then stopped and ran the generator for another 3 or 4 hours, my batteries would be at or very close to a full charge.

So yes, if we want to be technical about it and batteries have been depleted enough that the Converter Boost Mode has to kick in, then it could take 10 - 12 hours to fully charge and the generator would need ot be running that long.

[GVP-The Boxcar Children]

Timing is everything.
Just pulled our coach from storage this weekend, house batteries too low to even fire up the generator. Put the charger on for 8 hours overnight then at sun-up let the solar panel have at it for awhile. Then ran the generator for some time to get the house batteries back to a full charge. Good to go now.
Gary

GVP

[DavidEM]

Originally Posted by GVP-The Boxcar Children

Timing is everything.
Just pulled our coach from storage this weekend, house batteries too low to even fire up the generator. Put the charger on for 8 hours overnight then at sun-up let the solar panel have at it for awhile. Then ran the generator for some time to get the house batteries back to a full charge. Good to go now.
Gary

GVP

Don't do that very often. It is hard on batteries to run them down flat, particularly in storage where they may have been low for months. Why didn't your solar panel keep them up?

David

[Bob Denman]

Originally Posted by DavidEM

Don't do that very often. It is hard on batteries to run them down flat, particularly in storage where they may have been low for months. Why didn't your solar panel keep them up?
David

X 2...
This is why we pulled our batteries, and gave them a drink from our Battery Tender about every three 2weeks...

[IDguy]

Originally Posted by DavidEM

Don't do that very often. It is hard on batteries to run them down flat, particularly in storage where they may have been low for months. Why didn't your solar panel keep them up?

David

If you live north solar doesn’t do squat in winter due to short days and low sun angle.

[Bob Denman]

Originally Posted by IDguy

If you live north solar doesn’t do squat in winter due to short days and low sun angle.

Any solar power generated is a pretty good deal...

[GVP-The Boxcar Children]

Originally Posted by DavidEM

Don't do that very often. It is hard on batteries to run them down flat, particularly in storage where they may have been low for months. Why didn't your solar panel keep them up?

David

Indoor storage.... I will pull and store them for the off-season going forward.
Thanks!
Gary