Solar/Battery Decsion.

[bimmel20]

I think I have decided that I have enough roof space on my camper for three solar panels. I think I have finalized a decision on the Renogy 300w premium package to power my two GC2 batteries. Everything I have read says that you cannot have too much solar and you want to make sure and be able to top the battery charge off, so this makes sense to me. I really do not have anywhere else to put additional batteries and do not want the extra weight. Any nay sayers?

 

[rvpopeye]

Sounds like you're on the right track so far.
If that's not enough , just back off on your use a little till you find balance.

 

[SternWake]

300 watts to 232 AH of battery is OK, but if one is discharging below 70% daily, it will not be enough.

But keep the discharge cycles to 70% or greater with that capacity/solar wattage ratio and your batteries will be happy and long lived.

One can go lower on the discharge%, if other charging sources are available to get the batteries upto 80% charged relatively quickly, and then let the solar take the rest of the day to finish.

It is difficult to have too much solar, and far too easy to have too little.

 

[bimmel20]

300 watts to 232 AH of battery is OK, but if one is discharging below 70% daily, it will not be enough.

But keep the discharge cycles to 70% or greater with that capacity/solar wattage ratio and your batteries will be happy and long lived.

One can go lower on the discharge%, if other charging sources are available to get the batteries upto 80% charged relatively quickly, and then let the solar take the rest of the day to finish.

It is difficult to have too much solar, and far too easy to have too little.

So using this setup, I would optimally only have about 70 AH available per day?

 

[SternWake]

My 198 watts of solar flat on my roof averages 62Ah returned in Summer, and ~40Ah returned in winter.

Keep in mind one needs to return 105 to 115% of what was taken from a battery to fully recharge it.

The deeper the discharge the higher the %. The healthier the battery the lesser the %

If you get t-105's you want to see 14.8v absorption voltage by 1PM or earlier on a good sunny day. If you do not reach it by then, use less electricity overnight or employ additional charging sources so your solar can hold 14.8v for the time required for specific gravity to max out.

http://www.amazon.com/OTC-4619-Professional-Battery-Hydrometer/dp/B0050SFVHO

The above product is the flooded battery polygraph. Verify 100% with this and this only. Guesses can be wildly off.

 

[akrvbob]

It's a very good plan, charging it off your batteries would be the only improvement.
Bob

 

[bimmel20]

It's a very good plan, charging it off your batteries would be the only improvement.
Bob

When you say "charging it off of your batteries" are you referring to the tow vehicle battery?

 

[akrvbob]

When you say "charging it off of your batteries" are you referring to the tow vehicle battery?

If you have a trailer, yes, you can charge off the tow vehicle. Unless you have a flat 4 connection, then it doesn't have the charging wire in it and you would have to add it. I'm also assuming you have a properly wired RV trailer.  If you converted a cargo trailer you will also have to add it.
Bob

 

[SternWake]

I recommend a dedicated charging path from alternator to depleted batteries located in trailer. of at least 8awg thickness. Much more effective recharging in a shorter timespan.

Just Make sure to unplug this when parked and consuming trailer battery, or rig upto a continuous duty solenoid for full automatic function, or just trip this circuit breaker by pressing the red button on this circuit breaker. Move lever to complete charging path

http://www.amazon.com/Bussmann-CB18...8&qid=1452913113&sr=1-4&keywords=100+amp+fuse

http://www.amazon.com/Keeper-KTA141...sim_263_1?ie=UTF8&refRID=147ND97WNXYBJX94R5M6

These types of connectors can go upto 500 amps accepting 0 gauge wire if one has complete overkill on their mind.

Proper crimping of large terminals required. Protect cables from chafing.

http://www.amazon.com/ProDeals®-Sha..._UL160_SR160,160_&refRID=1GPBB1K9GRGVY4AKZSZV