Please, need help setting up a solar system with batteries and inverter, etc.

HenryJ

Expedition Leader
Connected parallel (+to+) two six volt batteries will provide 6 volts as shown in the above examples. Connected in a series ( + to -) two six volt batteries will deliver 12 volts.
 

java

Expedition Leader
/snip

What kind of DC fridge do you have and how many amp hours does your heater blower use?


/snip.

RV fridge, Norcold i belive, but its 12V only, no propane cooling. Its labeled as 4 amps when running.

The heater is a larger RV unit (10-15k btu ?) but not sure of its amp draw. But it moves a lot of when its running.
 

4RunAmok

Explorer
Think of batteries that go into a flashlight.

Two 1.5 volt AA batteries "stacked" in SERIES makes a 3 volt battery bank.

The flashlight gets positive from the nose, and negative from the tail.

6-volt-series.jpg


6-volt-series-parallel-4.jpg
 

Joe917

Explorer
Your Trimeric 2030 is an excellent battery monitor, essential to keep track of your systems performance. It is not a charge controller however.
The Trimeric needs a shunt on the negative side of the battery to monitor charge levels.
You need a charge controller (about 45 amps for 500watts at 12 volts, bigger if you want room for another panel.)
 

4RunAmok

Explorer
Starting from the top...

The solenoid is not shown wired correctly, it should be on the positive post that the loads are connected to. Solenoids that have three posts, two large ones for the positive wires from each battery and a smaller one for the signal wire from your combining circuit (Ign, or Acc, Combine switch, etc), these ground through the body of the solenoid. Solenoids with two large posts and two small posts ground through one of the small posts, the positive and negative posts of the coil inside the solenoid.

The shunt shouldn't have positive running through it.. Ground from the battery should be connected to one side, ground from your load is connected to the other side. The shunt will have smaller connection terminals for the signal wire that will go to the trimetric. Some shunts read from a positive connection, some from a negative connection.
shunt-wiring.png


Your batteries are still not shown wired correctly, mostly because you are not showing any ground lead, other than the incorrectly diagrammed shunt.

This was just a quickie diagram, but should give you an idea.. The only thing I'm iffy about is which side of the shunt the chassis ground goes on. Do your research/follow the instructions included with the shunt.
battery.gif
 

magentawave

Adventurer
Hey thanks for taking the time to do that! I really appreciate it. My updated diagram is attached. I basically re-did yours just so I could familiarize myself with everything a little better. I will research which side the ground for the shunt comes out of. What do you think?

EDIT: See my next post below this for photos of the Solenoid under the hood.

6-SOLAR SYSTEM.jpg
 
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magentawave

Adventurer
You were wondering about the ground for the solenoid under the hood so here are a couple photos of it. You can see the bracket for the original house battery too but my two house batteries will go in the back somewhere instead.
20140312_082115.jpg20140312_082021.jpg
 

DiploStrat

Expedition Leader
Two Quick Comments

-- For the shunt to work (that is, allow the TriMetric or other meter to give a valid reading) is is critical that none of your loads be grounded back to the camper battery without going through the shunt. They must all be earthed to the high side of the shunt. The shunt must be the ONLY path back to the camper battery. If you use your frame as a negative ground, then the shunt must be placed between the frame and the negative terminal of the camper battery.

-- Junk the solenoid you have under the hood and all of the related wiring. The wires are much too small to ever allow you to get a good charge from your truck's alternator. There are tables that will allow you to size things properly, but a a gross rule of thumb you can expect a 1/0 cable to pass about 75A. How big is your truck's alternator? You need a cable big enough to carry the full output at least 15 feet.

I would recommend using the appropriate Blue Sea Automatic Charging Relay. http://www.bluesea.com/products/category/Automatic_Charging_Relays This will have the advantage of allowing your solar kit to charge your starter batteries at the same time.

OK, a third and fourth comment:

-- None of this will work unless your truck's alternator produces at least 14.2v at 70F. (That being the minimum voltage for most deep cycle AGM batteries.)

-- Your cabling, down from the roof, from your solar controller to your camper batteries, and between your starter and camper batteries is large enough. Voltage drop on 12v systems is fatal. You need to aim for no more than 0.5v drop; less would be even better.

Good luck!
 
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4RunAmok

Explorer
Indeed, everything Diplostrat said.

Lordy, the battery wires on that solenoid are barely larger than the coil wires! I agree, it needs replacing with a good ACR, go with the Blue Sea 7622.
 

Herbie

Rendezvous Conspirator
Lordy, the battery wires on that solenoid are barely larger than the coil wires!

I wanted to say the same thing. Those wires are NOT big enough to connect to a battery, IMHO. I used #2 jumper cable with the clamps cut off...
 

4RunAmok

Explorer
There's an issue with that. I didn't want to bring it up in Evl's awesome cheap dual battery thread... buuuuttttt...

The only thing that worries me about using Jumper cables is the insulation. Most "value" jumper cables use a good amount of copper, and some are quite flexible like welding cable, but the insulation sometimes feels cheap and therefore dangerous. Should it be susceptible to temperatures (prolonged exposure to heat for example), it can harden, which leads to cracks, which leads to exposed copper, whic....well you know where this leads.

Other than that, they're a good way to get a lot of copper in place cheaply. I would do what I could to protect that wire from the elements, like split loom, and then cover that split loom with electrical tape end to end (or at least on the exterior sections).
 

4RunAmok

Explorer
What are those two little things in your image that are before and after the cars solenoid?

It's a breaker.

breaker.jpg

Required. I like breakers, some others like fuses. It's recommended to use 175 Amp or better between batteries.

Copied from my post in Bbasso's thread about his isolator.
you NEED to have fusing, or breakers... Because you have a battery at each end of the cable, you need a fuse or a breaker ("protection" from here on) at each end. If you do not, and a short occurs in the middle of the cable, having protection at only one end still leaves the other battery connected to the short, and it will continue to short out. Having protection at both ends, if the cable shorts in the middle, both fuses will blow or breakers will open, and the batteries are now protected from the short.

Protection should be within 18" of the battery at each end. I say 18" because within that distance, it is very unlikely there can be a short between the protection and the battery. My personal preference is a cooper bussmann breaker, it should be at least 175 amp if you ever intend to use the aux battery to "jump start" the main battery.
 

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