Well I have been negligent in writing my blogs, but the great adventure is really keeping us busy. We left New Hampshire the third week of October after installing solar, a big battery bank, and a Magnum 3000 inverter/charger/converter.
Since then we have driven across the middle of the country covering parts of the Old Lincoln Highway swinging northwest at Salt Lake City into Seattle. We spent time there getting to know a new grand baby before heading south along the coast to San Diego. We spent time there with family and headed into the desert of Arizona where we are currently. Yes we experienced Quartzsite and the Yuma Territorial Prison and long term boondocking. And yes solar works regardless of what the doom and gloomers say. While our limited solar array (170 watts) does not fully support our life style, which I will be the first to admit we are not energy efficient, it cuts generator time by at least 50%, and that is significant. Before next years trip I will add one more panel and rig them so that they can be tilted catching more sun.
But there are a couple of comments and e mails that I would like to address.
Question
Don T. wrote:
I have my 5th wheel setting at home, not being used, plugged into 50amp/convert to30amp land line………question is, am I hurting or helping my battery situation as I’ll be parked until June.
I’d appreciate any comments for this Dumbo…….Thanks
Answer
The answer is that generally keeping the battery fully charged and active is better than letting the battery sit. Now with that said it depends on the quality of the converter/charger that you have on board. Good units will vary the charging voltage and keep the batteries from over charging. Next make sure to keep an eye on the liquid level in the battery unless it is a sealed top maintenance free battery. Lastly check the batteries every once in a while with a voltmeter to make sure the charger is not running away. Anything between 13 and 14 volts is OK.
Question
Brad, the question is how long does it take to charge a battery in your rv? If you have a two 1000 amp batteries that is 2000 amps, How long will it take to charge them, each battery has 250 amps 500 total for both, with a 20 amp charger?
Answer
OK, now we get into the now you see it now you don’t relm of batteries. There are two distinct ways of identifying battery power. The first is the most common rating seen on automotive batteries and it is Cold Cranking Amps, or CCA. It is a measure of how many amps a battery will put out at a certain temperature and load. I think from reading your question that you have 2 batteries with a CCA of 1000 amps each.
The second rating is how many hours a battery will deliver a specified number of amps before dropping below 9.6 volts. That has been a standard as long as I can remember which over 50 years is in the field. It appears that is the second set of numbers that you quoted in your comment. This number would be listed on the battery label as a number followed by AH.
A battery with 1000 CCA would be about a 250 AH battery. However it is the AH that you would use when figuring charge time. If your battery charger puts out 20 amps, then it would take 10 hours to charge a battery with a 250 AH rating that is fully discharged. The higher the number of amps that the charger puts out the shorter the time to charge the battery. This is, according to as some have commented, on Brad’s fuzzy math. That means that it is not laboratory perfect to the tenth decimal point but more than close enough for real world shop application.
Well that is enough for this time and till next time keep on camping.
Brad Sears
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Thomas Bender
I’m afraid of using a propane heater in any enclosed area.
Alan
Hi, I’d love to know more about Quartzite. Could you give us some pointers?
Barry Zander
Our question: We have a flat 80-watt solar panel on the roof of our 28-foot all-season Bigfoot trailer, but a couple of times during the past year when we were dry-camping (as full-timers) and couldn’t use our Hondas at night we ran down the rwo 12-volt batteries at night. Before deciding to add an additional larger panel, I asked an RV expert at Quartzsite if we needed to spend the money. It seems to me that the only thing draining the batteries was the fan on the propane heater in our trailer. He agreed, and also advised us to make sure the auto climate control for the freezer was off (we found the control; it was off). We decided to buy a portable propane heater for inside the trailer, which we still plan to do. Why should we go to the expense of getting the second panel?
mk dawson
When I’ve got my rig parked at home and plugged into a 30 amp electric socket..should I have the house battery switch on or off?
Don Ritchey
Hi Brad a silly question. I have a solar unit in my class A that was an add on my question is when I want to use the solar as power I have to plug in the big external power cord to the 2400 watt sine wave inverter. At this point in my mind the inverter is doing 2 things, supplying power to the coach “and” charging the battery bank ( 4- 6 volts). Should I be unpluging the battery charger as it draws juice to keep the batteries up at the same time as I am using power in the coach so it would deminish the amt of available amps by leaving it on line?
Another RV owner said I needed to unplug the charger every time I use the solar only power and it has left me with doubts ever since?
Don Ritchey
Terrace BC Canada
Russell southerland
I am not sure that you will have full alt out if the start batt is the ref i think you will have min
russ