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Solar wire run

November 13, 2017, 11:31:38 am

As some of you are more solar experienced than I or my guru buddy is on my exact coach I need someone's experienced help.

We currently have 270 Watts of solar panels running down the refer vent and attached to the 12 volt system at the refer.

The wire size restricts the voltage to 13.6 nominally.  It's winter and the lower sun angle has dropped the output enough to barely keep the batteries up in storage.

His thought was to install at least one more solar panel and drop a direct wiring run to the batteries.

My batteries are in the compartment behind the drivers side front wheel well. 

Did someone post here about using the already present thermostat run on the sidewall to access the batteries directly?

How do you access that run?  Or is there a better way to get from the roof to the house batteries?

At the isolator?  We have a combiner but the battery cables run to it.

Need experiences getting to the batteries from the roof.

Thanks in advance

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Re: Solar wire run

Reply #1 – November 13, 2017, 11:46:11 am

I have ran them different ways in FT's Bob. You can still go down the refer vent, but drill a hole in the bottom of the refer cabinet, continue wires along the floor line , then through the floor to the batts.
Mine make a turn  in the refer cabinet, come out in the cabinet by the sink for the control. He used the wall chase to run the wires.
I have used the extra wires in the belly to also run batt. sensor's, or there is 2 # 8 wires I believe also, if you want to come from the back to the front.
I have also installed the controller several times in the side of the cabinet at the sink. So wires down refer vent, through cabinet botton. to controller, then inside cabinet to batts.
Chris

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Re: Solar wire run

Reply #2 – November 13, 2017, 12:11:26 pm

Mine come in the frig vent the #6 into the basement to the cable tray to the inverter bay where the outback controller is. The negative cable goes to the shunt for the link 2000 for keeping track of things.

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Re: Solar wire run

Reply #3 – November 13, 2017, 12:41:20 pm

Caflashbob,
 Best advice I can give you is:

Mount your solar collector orientation at an angle equal to your latitude.

You can see the improvement on a meter and the cost was negligible. Mounted mine on a tobacco barn and used items most people have like an electrician's level, a .50 cent plastic protractor ruler for the angle, and some shims and tape or Velcro to wrap the shims.
Use the level's bubble  to start from level and than match the angle on the protractor sitting on the level level  (LOL)  and shim or mount in place.
Cost effective and works.
John

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Re: Solar wire run

Reply #4 – November 13, 2017, 01:06:29 pm

Bob,

What are the specs on the back of the solar panel? Where is your solar controller mounted? Is it a MPPT controller? The best way is usually to wire the roof panels in series. Double the voltage then the wires only have to be half the size. Good MPPT controllers with your anticipated roof wattage are excellent and cheap. Combine solar #8 on the roof to series with two #8 down to the controller. I made my own bus behind the controller so I used #8 out of the controller about 10 inches to the bus and then used welding cable to the electrical panel with the house battery cables to it. See my photos in previous posts. Somewhere between 13.1 to 13.6 is a good float voltage.

If you don't tilt your roof panels (we don't), you can use removable reflectors to bring the wattage up. Flat white paint on a lightweight board works the best. Better than a mirror.

Pierce

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