Renogy solar?

"allowed gen times", for God's sake... Too often too many people choose to exercise this their "right" and run a generator from 7 am to 10 pm. For all kinds of reasons: microwave - like they would've died without it, toaster, espresso machine, breadmaker, iron, big screen TV, you name it... I'm trying to avoid such places. Ever heard the sound of a "quiet" diesel generator? It's un-f-king-believable.

HiTech - there is almost no output in rain. You'll get lucky to have few amp-hours from 400W panel.

I been getting 2 amps/ out of 200 watts most the morning, partial sun, but panels mostly shaded from trees, But I think its looking better now, and the rest of the day.

That panel-clad U-Haul trailer with the flip down side panels, batteries inside with the inverter sure do look good at times methinks. Especially on a 35C sunny day.

Yep, its a whole lot better now, 10.4 amps out of 190 watts. It don't get no better.

RJ, your set up is working fairly well, but what is the Isc of the panels? My two 100s have Isc of 6.3 (actual) (6.4 published, with 5% tolerance) and I do get that 12.6a when pointed in full sun showing on the Trimetric at the batteries.

Proportionately, 190/200 x 12.6 = 11.97. If 10.4 is the best you get, then perhaps your panel Iscs are lower. If so, are the Vocs in the 22v range instead of 21v range?--that's something I have noticed lately. OR, you are losing 1.5a somewhere.

Today we too had a cloudy morning with clearing in the afternoon.
What a pleasure to be able to twirl the contraption into the sun when it came out, and make hay while the sun shines! :)

What is Vmpp on your panels?

Jim

Not sure who the question was for. My 100s are Voc 21v, Isc 6.4a, Vmp 17.5v, Imp 5.71a, with 5% tolerance stated. I have two of these and sure enough one has higher Isc actual than the other 6.4 and 6.2 so av is 6.3. I do see the 12.6 total.

I am not upset with this, since my 130w Sharp panel of supposedly higher quality than these Suns (heavier frame, fancier junction box etc)) gets 8.2 Isc as spec, and 100/130 x 8.2 = 6.3. So I am happy to get 12.6 max to go with the 130's 8.2 and get total max of 20.8a normal at high noon. ( I have seen 26.5a in cloud effect so far--no idea how high that can go)

On earlier question, I do get some amps when it is overcast but it varies with how much brightness is getting through. Low amps anyway, so not worth much in the big picture (which was my real point)

Hi BFL13,

Any time the solar is meeting the parasitic loads in an RV the battery bank is "getting a rest" and perhaps even a smidgen of charging. That's good for the bank, especially after running a microwave or other heavy load.

I'm just saying low amps may not seem a big deal--but they do more good than many may think.

PT, I suppose you are right; you can join smk in his belief that a slow charge has a "higher quality" than a fast charge that gets the battery to the same SOC.

I don't care really, I just want that SG to show the battery is up where I want---the sooner the better!

The thing is, I don't believe when the SG gets there with a faster charge that it will then fall back, where if only it got done with a slow charge, it would stay there.

Doesn't matter while camping anyway. At 5pm, or whenever, when battery SOC has peaked, it is time to start supper and eat up some AH and that's that for SOC. Any solar from then on is nice, but can't keep up with usage till dark.

Hi BFL13,

Since SG is a measurement of the density of the fluid the only ways it can go lower are self discharge, addition of more distilled water, or mechanical stirring of the fluid.

Self discharge on older cells can be 1% per day.

I've always believed in slow charging, but not because it is "higher quality". It does lend itself to less sloughing off of positive plate material.

I'm always learning new "stuff" and in another thread today I learned that the detritus from plate shedding can be a conductive liquid which "sits" in the well below the plates. When that liquid eventually starts to touch the plates it slowly increases the self discharge rate.

I also believe in what is called "saturation" charging where a low current (200 milliamperes) is applied to the battery for 14 to 16 hours. Most solar systems can't deal with that--so bank switching can be used where one bank is deliberately used to do a 14 to 16 hour charge on the other.

Saturation charge is one reason I do "opportunity" charging on shore power as often as I can.