I am planning to add a solar panel on the roof for house battery charging. In my 92 Regency, I can't seem to find a suitable route to run the wires. I can get down the refrigerator vent OK, but geting through the floor and snaking the wiring throught to the engine compartment poses a challenge.

Has anyone done this before? The technicians I've spoken with say Barths are built so well, it complicates running wires.

Well, we all know they are well built, but there must be a reasonable solution, short of opening up a wall.

If you have some experience with this, please advise me.

Bill G

Before too long, I'm going to add solar, but I've decided to mount the panels on a tripod and place them outside on the ground.

The reason, in addition to what you've mentioned, is that for best performance, solar panels should be perpendicular to the indidence of sunlight, and that's nearly impossible to achieve with a fixed array - or even one that can be tilted, as you might not be able to park for the best angle.

Keeping them portable also allows them to be stored inside and kept clean and out of harm's way.

what is wrong with putting them in the windshield and letting them protect the interior while they charge your batteries?

I would be very hesitant to permanently put something like that on my roof. Damage is one problem, just going down the road.

If you want to run your own wires, it is not too difficult to drill through the floor inside the cabinet under the fridge. We had a water tank under the fridge that had to be removed to install the wires. You may already have sufficiently heavy 12 volt wires to the fridge for the 12 volt heating element. There is a very heavy wire going from the battery to the genset starter that is handy for a connection. Any connections underneath benefit greatly from Liquid Electrical Tape.

Portable panels are really handy when you are parked under a tree, too.

billh,

Your suggestion to use the original 12 volt wires to the refrigerator has some legs. I put in a new Dometic refrigerator two years ago. The old unit had a three way system; one was a 12 volt heater. The new unit is only two way and does not have this option, so I may have some unused original wiring I could use.

How would you trace back the routing for these wires from the refrigerator compartment to the battery?

Bill G

quote:

Originally posted by Bill G:
How would you trace back the routing for these wires from the refrigerator compartment to the battery?

Bill G

Bill, I'm not sure I understand the question. There should already be a big hot and ground in your fridge cavity. Why do you want to trace the routing? But, I guess I would just do it visually from underneath.

bill h,

I guess I'm thinking (perhaps incorrectly) that it is important to feed the solar output as directly as possible to the batteries. If this is correct, wouldn't it be important to know if there is a series of connections on the positive wire that could siphon off some of the solar feed?

My solar panel and photovoltaic regulator require a 10 ga. wire to be used.

Bill G

quote:

Originally posted by Bill G:
bill h,

I guess I'm thinking (perhaps incorrectly) that it is important to feed the solar output as directly as possible to the batteries. If this is correct, wouldn't it be important to know if there is a series of connections on the positive wire that could siphon off some of the solar feed?

My solar panel and photovoltaic regulator require a 10 ga. wire to be used.

Bill G

Yes, the more direct the connection, the more efficient it will be. This applies equally to all electrical circuits, solar or not. Also, perfectly clean connections and heavy wiring help. So, it would indeed be a good idea to trace the wiring visually, and disassemble and clean all connections from the fridge cavity to the battery. Connections, in and of themselves, do not do anything bad as long as they are of sufficient size and stay clean. I would also go to 8 gage wiring just in case you buy another solar panel or two in the future. If your panel will not accept 8 gage, solder a 10 ga pigtail on the end of the 10 ga wire at the panel. Be sure to buy UV resistant wire for the roof. When you install the panel, leave room for one of two more, so you don't have to move it if and when you want another. Also, buy a big enough control panel for the same reason.

Everyone, thanks for your advice.

I have successfully created routes for the wires to run from the roof to the regulator on the interior wall and then through the base of the refrigerator and then though the floor under the refrigerator to the under body. I have also pulled some nylon rope through the floor and out the interior wall as well as from the roof to the interior wall.

I have purchased a Go-Power 25 amp digital photovoltaic regulator and a roll of red and green #10 stranded wire to use for the run from the regulator to the bateries.

The purchase of the panel must wait a bit, but will include the UV resistant cable and a 125 watt panel from RV Solar Electric (Approx. 25" X 56"). I'll start with one panel, and may go with a second next year.

To keep things simple, I will run the wires from the regulator directly to the house batteries to avoid connections that could sap some of the solar feed.

The technician at RV Solar Electric said that when running on the house batteries, you know when to recharge the batteries when the regulator is around 12.1 to 12.0 volts. Anyone else have any thoughts on this?

Bill G

quote:

Originally posted by Bill G:
The technician at RV Solar Electric said that when running on the house batteries, you know when to recharge the batteries when the regulator is around 12.1 to 12.0 volts. Anyone else have any thoughts on this?

Bill G

Yup. He's about right. How deep to discharge is an individual choice, and it involves a trade off. The deeper you discharge the batteries, the shorter their service life, but the fewer batteries you have to buy and carry around. And, a less deep discharge will give you longer-lasting batteries, but you will have to buy and carry more to get the same amp hour usage.

Too shallow a discharge will also result in a shorter service life, so the batts should be taken down below 80% of capacity each discharge cycle. And taking them below 20% of capacity is really hard on them.

So, 50%, which is 12.1 volts, is a pretty good compromise. That is what we use.

But, it gets a little complicated. That 12.1 volts needs to be read after the batteries have sat for several hours, preferably 24 hours without charge or discharge. You will be fairly accurate if you have no overnight discharge and read the voltmeter before the panel sees any sun. A hydrometer reading is valid any time, but is a pain. Plus, they break if you step on them. My own solution is a TriMetric 2020 meter. www.bogartengineering.com It gives a percentage reading which is valid at all times, as it keeps track of charge and discharge. The price of one can pay for itself in making your batteries last longer and keeping you apprised of the batteries condition. This can also help you avoid the inconvenience and expense of buying overpriced or less than ideal batteries at the wrong place and the wrong time.

Also, it is not efficient to attempt to charge above 80% with a generator, as you will be using the same amount of fuel to push fewer amps as the batteries leave the bulk phase of the charging cycle. You can bring them up full when you get home and the sun can do it with no nightly discharges or plug it in.

Depending on your usage, the 125 watt panel might be enough for you. We were pretty good with a 65 watt, but we don't watch TV. We now have 165 watts and last weekend the batts were 100% well before noon with the panels flat on the roof. In January, we had to tilt the panels after the first week out to keep the batts from going down. I use a 1 1/2 watt LED array as a reading light, and my Susan uses a 5 watt MR-11 halogen reflector lamp.

Bill,

How about a 4" conduit next to your dining room table? You could cover it with carpet and it could double as a scratch post for the new family cats!