Solar amp hours in real life

[Forest Grump]

I just use the solar controller and no longer use a battery monitor. They are hard to program and harder to interpret the data. With a good controller and conservative wire sizes I let the batteries and panels do their thing. I do this because there are no actions you can take. I don't know what your settings should be for the crown battery, 14.8 seems high for the adsorption cycle.

[jackfish]

I guess you haven't read or understood Handy Bob's blog?
https://handybobsolar.wordpress.com

[okcnewbie]

Originally Posted by Forest Grump

I just use the solar controller and no longer use a battery monitor. They are hard to program and harder to interpret the data. With a good controller and conservative wire sizes I let the batteries and panels do their thing. I do this because there are no actions you can take. I don't know what your settings should be for the crown battery, 14.8 seems high for the adsorption cycle.

That's interesting; We spend all this money on our rigs and can't/won't have a good monitor that can give you peace of mind. I suggest that even people that don't want solar get a good monitor. If you use it watch the amps from time to time it can help you recognize what's going on with the alternator, converter and pretty much everything in your coach.

[Forest Grump]

Yes I did read Solar Bob. I took what he wrote, applied what would work for me and applied much of what he said. My solar controller for example - Morningstar TS-45 TriStar 45 Amp Charge Controller 12-48V PWM with REMOTE DISPLAY set at 14.6v adsorption for Trojan L batteries, like he did. Remember Solar Bob was also writing about solar for his physical home.

The solar controller display tells me everything I need to know. The controller automatically maintains my batteries. From day one it told me my batteries were receiving the maximum voltage and amperage that the panels could put out and controlling the process through float. I can do nothing to enhance or improve what is happening. A separate monitor would not give me anymore useful info. If I have sun I have fully charged batteries every evening.

It's a pretty simple system. Plug and play assuming you have the correct physics, I do. It works so I don't have to.

[elkski]

I am not sure I set my trimetric numbers correctly. I posted them in this thread and no one commented on them.
http://www.irv2.com/forums/f33/lance...-253735-2.html
I used the 14.8 per handy bobs understanding of crown batteries. I may have not put the 14.8 in the correct parameter? P1? tihs is the voltage at which the battery is charged or less than 2% of battery capacity in amps 2% of 115 ahrs.

[Forest Grump]

Originally Posted by elkski

I am not sure I set my trimetric numbers correctly. I posted them in this thread and no one commented on them.
http://www.irv2.com/forums/f33/lance...-253735-2.html
I used the 14.8 per handy bobs understanding of crown batteries. I may have not put the 14.8 in the correct parameter? P1? tihs is the voltage at which the battery is charged or less than 2% of battery capacity in amps 2% of 115 ahrs.

The above is what I mean. First do you just have the amp/meter or the amp/meter solar controller. Initially the charge going to the batteries should be what they can take. Then when this starts to drop off, the battery is about 80% charged the adsorption phase starts, which you have set for 14.8 volts I hope. I would change this to 14.6 for safety reasons. You said you saw 15v, for example. Solar Bob sets his 0.2 volts lower in his RV. Your last sentence I don't understand.

The last phase, float, is where the batteries are now charged and being maintained.

[elkski]

I will change the adsorption to 14.6. IT was 10 am after a frosty morning so maybe the 15 was temp corrected. my last sentence? I guess adsorption shuts off at 14.8 or when current drops below 2% of battery capacity. so .02x115=2.3 amps. Even the chart for the standard battery settings shows many batteries as 15.9 for max voltage? I basically used the crown settings but I swear I remember Bob saying he used 14.8v?

page 16
http://www.bogartengineering.com/sit...ersInstruc.pdf

[Forest Grump]

He does but not in his RV. Desulphonization uses the higher voltage. You have to remember the higher the charging voltage the more hydrogen that can be released. See ifyourbatteryis gassing at14.8. See what Crown recommends.

[757driver]

Why not listen to the various battery manufacturers web sites and set absorb and float voltages according to what they have to say. Even Handy Bob agrees with this one.

[757driver]

Originally Posted by Forest Grump

The above is what I mean. First do you just have the amp/meter or the amp/meter solar controller. Initially the charge going to the batteries should be what they can take. Then when this starts to drop off, the battery is about 80% charged the adsorption phase starts, which you have set for 14.8 volts I hope. I would change this to 14.6 for safety reasons. You said you saw 15v, for example. Solar Bob sets his 0.2 volts lower in his RV. Your last sentence I don't understand.

The last phase, float, is where the batteries are now charged and being maintained.

The only reference I could find in HandyBob's blog with reference to setting 14.6v absorb instead of 14.8v absorb is with reference to motorhomes (not a 5th wheel as Bob has). With that statement should also list Bob's reasons for this which is " I set controllers in motor homes slightly conservatively (14.6V) due to the chassis battery interconnection and over voltage alarm problems. I don’t like it, but there doesn’t seem to be much choice."

If the chassis battery(ies) can take the higher voltage and there are no over voltage alarm problems then set the absorb voltage where the battery manufacturer suggests.

[Forest Grump]

The issue he had was with his inverter and its maximum voltage. Trojan recommends 14.8 for many of their batteries, which is what I have. Xantrex inverters will alarm at 14.8 to 15 v which is what I have. My coach is stored and primarily used in dry hot desert conditions. I set the adsorption to 14.6. Less gassing, less hydrogen no alarms with inverter. My battery, my choice and the system works fantastically. We get 300 days of sunlight per year and a lot of hours of sun each day. That's why in the 18 miles between me and where we store Casper there are about 7 solar farms.

I haven't found a charger or converter that can be set to an adsorption rate of 14.8 or 14.6, interesting huh. There might be some but I'm not in the market for one.

[Reed Cundiff]

Handybob can be useful and he has his opinions. Folks can get carried away about their positive and/or negative opinions of him. We have exchanged e-mails several times and he has been helpful but he does want things simple and is not happy with more modern techniques/methods.
Reed and Elaine

[Forest Grump]

Reed: couldn't have said it better. He offers general guidelines and more importantly warns you of problem and failure areas. What I got from him was conductor size, conductor size, conductor size. You take what fits, what works and do the best you can for the $$$$ you have.

I was super conservative on conductor size, total panel wattage, controller etc. mine works exactly as designed. The power I use is replenished in two hours and then the rest of the day the solar power is utilized to condition the batteries, at 14.6v till float.

[Reed Cundiff]

Handybob is superb for beginning solar of moderate power levels and energy storage. His work is all that is required for most folks who wish to use solar.

Go to "Arizona Wind and Sun" or "Solar Panel Talk" if you want to read some folks that really think everyone else is an idiot, and say that implicitly. The Aussie "Caravaner's Forum" is also filled with vituperation. I enjoy IRV2 and the Escapees Forum since both are utilized by folks that want to helpful, not trying to impress, and not cutting each other.
Reed and Elaine