Coach batteries won't last one night

[NWIP]

Credit needs to go to @Chuggs, I was gleaning all the info he posted and learning myself?

 

[TJ&LadyDi]

Credit needs to go to @Chuggs, I was gleaning all the info he posted and learning myself?

Oops! Sorry, Charlie; getting things right wasn't my strong suit yesterday. Mea culpa! It was a great summary, nevertheless, @Chuggs.

TJ

 

[Kevin D Pem]

Another thing, are you sure the batteries are getting fully charged? Are you completely dependent on the solar panels to charge the batteries?

@Jim is spot on with the charge. I maintain that the weak link in any electrical system is not the battery bank. No the weak link is the charging system. If your charging system shows the voltage is lets say 14.4 in the morning that only gives about 3 hours of bake time before the sun sets. I like to point out that like a cake in the oven, just because the temp is where it is supposed to be does not mean the cake is done. Did you know that the last 20% of the battery charge for your bank (4x6v bank) if charged in a way as to not hurt the batteries will take in excess of 10hrs?

Lets look at my numbers:

My system has 8 panels (8x250w)
Three controllers
2 x 200 ah AGM batteries set up for 24v system.

because I only have room for 200ah of batteries my controllers will not pump more than 750w of power in them in the morning. By noon the output of one controller has gone to 0w and the other two are producing less than 60w apiece.

There is nothing wrong with my panels or controller they do as they were designed. They were designed to protect the batteries first and being MPPT designed second to get as much power out of the panel when needed. After a week of cloudy skies the controllers require a full week to top of the battery bank, and my bank is considered small.

My refrigerator has a KWYr rating of 345 so it is designed and tested to use less than 1kw a day. (look for a yellow EPA tag online for your fridge). It will run on 280w solar panel with no problem on sunny summer days. I have no idea if that is true on winter days.

You can figure if you have 100w panels you will get maybe 75w mid day. with that info you can guess or if you are really good with math figure the power curve for the number of daylight hours to see how many watts actually make it to the battery bank after the resistance of the battery.
for people with limited solar I recommend the use of a generator for 3 to 4 hours to take care of bulk charging then let the solar do the rest.

 

[Chuggs]

Credit needs to go to @Chuggs, I was gleaning all the info he posted and learning myself?

No credit due...I learned it all from the community. Just trying to help others as I have been blessed with help from others.

Your mileage may vary, @Chuggs cannot be accountable for the accuracy of his content.

 

[AbdRahim]

It makes me wonder how long do these generators last? One year and I am over 100 hrs. They add up fast. Only have 10 w solar.

 

[Jim]

It makes me wonder how long do these generators last? One year and I am over 100 hrs. They add up fast. Only have 10 w solar.

Mine is a 2009 and shows over 6,000 hours.

 

[TJ&LadyDi]

The Onan generators are pretty bullet-proof. I expect that they will last at least as long as the coach.

TJ

 

[Jim]

The Onan generators are pretty bullet-proof. I expect that they will last at least as long as the coach.

TJ

And as an aside, I believe Cummins owns Onan. So I would think their product is pretty solid.

Cummins Power Systems and Onan - the history

www.nooutage.com

 

[Kevin D Pem]

I believe Cummins owns Onan

yes they do.