Community Forums

Texigan · 05-03-2009, 03:21 PM

Thanks Dude... Will do!

I check the water on the first day of every month and fill with distilled water if they need it...

Also wash them off with a baking-soda solution...

After 3 years, they are still in good shape and I aim to keep them that way.

Buck

John Hilley · 05-03-2009, 03:30 PM

Texigan said

"The house batteries are a pair of Werker 8DA, 12V, 1300 amp-hour, deep cycle batteries... they have been taken care of and are in good condition... testing under load indicates a minimum of 1241 AH available from each battery, even tho they are three years old... When replacement time comes, will consider two golf-cart 6V batteries in series if the math shows they would give me an increase in amperage capacity."

Actually those batteries are only 255 ah at the 20 hr rate, 8DA battery description the normal way of comparing deep discharge batteries. The GC2 golf cart batteries are about 225 ah. Your house battery relay may also be a latching type, only drawing current when switching modes. You should be about 50 ah to the good on normal sunny days. I have 450 ah capacity with 4 GC2 batteries and only 7 amps of solar charging available. I have to run my Honda EU2000i for about 2 hours a day to keep up with my wifes lighting and computer use.

Texigan · 05-03-2009, 03:55 PM

You are correct John... I went back out and looked at the batteries and the 1300 is the cold-cranking Ampere rating...

Didn't take off the cover and look at the house battery relay, just looked on the Country Coach Schematic and it shows the relay as a "normally open" DPST relay that is closes and connects the batteries when the switch is activated...

And in accordance with what both you and Dude say, I will be better off to stick with the 8DA batteries when I have to replace them.

Buck

shastaron · 05-03-2009, 07:25 PM

Keep an eye on your charge controller for the solar panels and I think you will find that you are only getting 3-7 amps most of the day. And only get 12 or more at the absolute peak of their exposure. It will start out as a trickle charge in the morning slowing peaking at 1-3 PM and then start to taper down again. That has been my experience.

Ron

Texigan · 05-05-2009, 09:14 AM

Ron... I turned off the AC this morning at 08:30 and checked my solar panel output... it was delivering 12.9V @ 4.3 Amperes... Checked it again at 10:00, and output was 13.9V @ 8.6 Amperes... Gonna check it again about noon and see what I am getting... In the past have seen it charge as high as 17.7V @ 15.6 amperes... At about 15:00, the panels are shaded by a large oak that is on the west side of my RV lot, but I still get a pretty good charge, even in the shade... Both of my panels are mounted flat on the roof of the RV... (they were mounted that way by the previous owner) If they were adjustable so I could change the "angle of attack", I think they would easily achieve their rated output of 10 amps each, giving me a total charge of 20+ amps... these panels are not the "standard" ones you see on most coaches... Don't know where the previous owner got them, but they are larger panels than you usually see... The charge controller is Seimens, so I assume the panels are also... will look the next time I am up on the roof...

Buck

John Hilley · 05-05-2009, 06:52 PM

I think the voltage level you have seen before is a little too high. I don't think you should let it get above 15.5 VDC on the battery side of the charge controller, you may however have been measuring it on the solar panel side of the charge controller.

Texigan · 05-05-2009, 07:34 PM

Thanks John and I agree that 17V is too high for charging 12V batteries... I was measuring the actual output of the solar panels... The charge controller/regulator is set to keep the charging voltage at a maximum of 13.8V

RVDude · 05-06-2009, 08:31 AM

I'll guess you have the custom made 44cell BP Solar panels up there sold by (AMSolar.com) Welcome to AM Solar - Your RV Solar Specialists since 1987 (or a similar high cell count panel) given the 17.7v output from a flat mount panel. These slightly "hot" running panels combine beautifully with MPPT controller technology to optimally play the ever changing volts and amps game to maximize charge depending on light conditions and charge type. Especially effective at initiating some level of charge even at low light levels.

Texigan · 05-06-2009, 10:43 AM

Don't really know what's up there Dude, but I suspect you are correct, as I start getting a meaningful charge usually by 8:30AM and it continues until evening even tho I have that big oak tree to shade me in the afternoons...

Don't get on the roof often, but next time I make an excursion up there, will see if I can find some sort of name tag or other info on the panels themselves...

Buck

Quote:

Originally Posted by RVDude

I'll guess you have the custom made 44cell BP Solar panels up there sold by (AMSolar.com) Welcome to AM Solar - Your RV Solar Specialists since 1987 (or a similar high cell count panel) given the 17.7v output from a flat mount panel. These slightly "hot" running panels combine beautifully with MPPT controller technology to optimally play the ever changing volts and amps game to maximize charge depending on light conditions and charge type. Especially effective at initiating some level of charge even at low light levels.

CMcCardell · 05-06-2009, 11:30 PM

Quote:

Originally Posted by John Hilley

Texigan said

Actually those batteries are only 255 ah at the 20 hr rate, 8DA battery description the normal way of comparing deep discharge batteries. The GC2 golf cart batteries are about 225 ah.

Correct me if I wrong, but wouldn't 2x GC2's (6 volt) give you 225 ah total in a 12 volt system, vs 2x 8DA's (12 volt) which would give 510 ah in a 12 volt system?

- Clay

John Hilley · 05-07-2009, 07:10 AM

Quote:

Originally Posted by CMcCardell

Correct me if I wrong, but wouldn't 2x GC2's (6 volt) give you 225 ah total in a 12 volt system, vs 2x 8DA's (12 volt) which would give 510 ah in a 12 volt system?

- Clay

Yes that is right, but you would use 4ea GC2 in series/parallel configuration for nearly equal capacity at substantialy lower cost. 4ea GC2 at Sam's Club would be $248, less than 1ea of the 8DAs. The 8DAs are about $650 ea.

jlb77399 · 05-13-2009, 01:00 PM

Hi,

Something that has not been mentioned is a meter to track both usage and input.

When I installed my 520W solar system I installed a Trimetric 2020 meter that does lots of stuff. http://www.bogartengineering.com/

The 17vdc you are seeing from the panels would be the normal output from a regular 36 cell panel. The 44 cell panels from AM solar would be in the 22 volt range.

With the controller set @ 13.8vdc max you are not completely charging the batteries. If you are really wanting to get the most from the batteries, you might consider, as another poster mentioned, look at a MPPT controller. Also might look @ Jack Mayer's site and read his take on solar. http://jmayer6.tripod.com/index.html

Jim
'96 Sahara 3540, 300 CAT, 520 W Solar

malibou moon · 06-09-2009, 11:28 AM

Thanks for all the tips. We just got back from our first dry camp in Sequoia w/our Itascha Sunova. We've had rental Class C's the last 3 years. Little did we know that a freak storm would move in and dump 2" of snow on June 4th!!

It was cold at night, low 30's and not quite 60 in the day, overcast. We ran the heater alot. I also had the brilliant idea to leave the water pump on. No wonder we woke up with no heat and no battery charge on the level test.

Generator helped alot. We just weren't sure if it was conditions or if something wasn't charging correctly.

Learned alot for next time.

RVThere · 06-09-2009, 03:12 PM

I added on/off switches to the bedroom and basement radio's which were always sucking power to keep the time displayed.

In addition to the automatic basement lights not going off, I put a switch on my closet light which was always going on whenever I opened the door. Or the closet slider would work it's way open a crack which was enough to turn the light on but not always enough for me to notice it.

A generator cannot always save you as most national parks have designated times to run your generator (not in the middle of the night when your furnace fan is sucking the last few revolutions out of your battery and DW is freezing!) or you may find the only open site is in the generator-free loop.