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rayza · 05-21-2018, 01:31 PM

I went to an RV repair shop today looking to get some work done. I asked about solar and he said it is pretty simple - I already have 6 AWG wire from the roof to one of the bays.

He said that all I really need are solar panels and mounting kit. That I don't need an inverter as the panels already are 12V and they can just be wired in parallel which will increase the amperage but not the voltage, and then just wired straight to the battery. He said I don't need a controller unless I am interested in seeing input/output. I don't really care about fancy monitoring, I just want solar panels charging the batteries.

Is he right on this, is there any reason I need to be looking at a controller or inverter?

If that is the case, I just want to buy 4 of these and mount them directly to the roof with no kit (just screw in the 4 corners) https://www.amazon.com/ALLPOWERS-Mon...e+solar+panels

A32Deuce · 05-21-2018, 02:04 PM

Not correct. Time for research or wait for more answers. Pop Corn ready!

weredoingit · 05-21-2018, 02:15 PM

Quote:

Originally Posted by rayza

I went to an RV repair shop today looking to get some work done. I asked about solar and he said it is pretty simple - I already have 6 AWG wire from the roof to one of the bays.

He said that all I really need are solar panels and mounting kit. That I don't need an inverter as the panels already are 12V and they can just be wired in parallel which will increase the amperage but not the voltage, and then just wired straight to the battery. He said I don't need a controller unless I am interested in seeing input/output. I don't really care about fancy monitoring, I just want solar panels charging the batteries.

Is he right on this, is there any reason I need to be looking at a controller or inverter?

If that is the case, I just want to buy 4 of these and mount them directly to the roof with no kit (just screw in the 4 corners) https://www.amazon.com/ALLPOWERS-Mon...e+solar+panels

At the very least you need a CHARGE CONTROLLER, unless you don't care about your battery's. You don't need a inverter, unless you want 120 volt power. As stated above, you really need to read up, before this guy touches your RV.

UFO Pilot · 05-21-2018, 02:24 PM

My charge controller regulates the charge rate and also sends 90% to the house batteries and 10% to the chassis battery. I wouldn't have solar without one.

I would almost guarantee that your RV already has an inverter. Seek better advice and do a lot of reading about solar.

PJStough · 05-21-2018, 02:36 PM

A "12 volt" panel can putout as much as 18 volts. Too much for 12 volt systems to handle without a controller.

rayza · 05-21-2018, 02:52 PM

It sounds like a controller is fairly cheap anyway.

I want to do a self install, I only want 4 of those flexible panels. Does anybody have a parts list that I would need?

MisterT · 05-21-2018, 03:16 PM

don't you already HAVE an inverter?

A simple charge controller comes with a lot of package panels, or is fairly inexpensive - but it monitors and CONTROLS the output to the batteries, it's not just for 'viewing' the solar amps. While the batteries could be overcharged without a controller, I think that maybe he was just saying that a small solar package probably is not going to cause any overcharging, but I would have a charge controller regardless.

He's right on the hookup, it's simple. Wiring from the panels to the controller, and then to the batteries - done. The inverter is not part of the equation. Nothing else is needed.

Craig1960 · 05-21-2018, 03:19 PM

Doesn't sound like the guy knows much about solar power. There is a lot of good info on this forum in the "Going Green" section that will help you make your decision. I was looking at the flexible panels like you are but was advised against them, so I bought the hard panels and mounted them on the roof.

C.Martin · 05-21-2018, 03:19 PM

I would find another RV shop...

Make sure your battery bank is where you want it in terms of storage capacity.

Then...design the Solar to recharge that sized battery bank...

You’ll get more out of the sun when the controller wakes up early, and goes to bed late...IE at least pairs of panels in series...connected to a MPPT controller. For best charge control...look for a controller with three stage charging...preferably customizable...and temperature compensation.

Panels,
Mounts,
Dicor,
Combiner box,
Circuit protection/isolation switches
Charge controller
Terminal hardware
Wire

It is also a great idea to add a battery monitor. These devices keep an eye on all the amps going in or out of the batteries and display your state of charge as a percentage. This is a great way to manage your batteries...and to figure out when it’s time to toss in the towel on a rainy day and run the generator.

Having four panels putting out 18v and 22 amps without a charge controller...will boil those batteries. I think you’ll ruin your battery bank in just a few days of that kind of abuse.

MisterT · 05-21-2018, 03:21 PM

yes, your Baystar already has an inverter, if for nothing else just the Fridge, but another outlet or two could be part of it's wiring, or there may be an outlet on the inverter itself, which is usually located under the fridge area in the outside bay, on the ceiling, or wall, etc.

for the solar, it is only for charging the batteries, it does not 'directly' power anything in the coach, whether 12v or 120v - that's what the Converter, Inverter, Shore Power, or the Generator does. Solar only provides recharging of the batteries, while you are away from external power and while not running the generator. It basically limits the time you need to run the generator.

C.Martin · 05-21-2018, 03:37 PM

Quote:

Originally Posted by MisterT

yes, your Baystar already has an inverter, if for nothing else just the Fridge, but another outlet or two could be part of it's wiring, or there may be an outlet on the inverter itself, which is usually located under the fridge area in the outside bay, on the ceiling, or wall, etc.

for the solar, it is only for charging the batteries, it does not 'directly' power anything in the coach, whether 12v or 120v - that's what the Converter, Inverter, Shore Power, or the Generator does. Solar only provides recharging of the batteries, while you are away from external power and while not running the generator. It basically limits the time you need to run the generator.

This actually isn’t true...when the Solar is charging the batteries...it is generating more electromotive force than the batteries...thus, the flow of current into the batteries. If you happen to have any dc loads powered at the same time...they will divert Solar to meet their demands.

I have graphs that show the output of the solar controller...and the current going in and out of the batteries...when the Solar charge controller is putting out 40amps...but the battery shunt only shows 22Amps going into the batteries...there is obviously 18Amps of something being “powered”... this is routinely the case on our coach every time the Inverter is powering the residential fridge during daylight hours... Solar IS powering the coaches 12v loads, 120v loads, thru the Inverter, AND charging the batteries. Of course this ends abruptly at sundown.

MotorPro · 05-21-2018, 05:18 PM

If a shop gave you that info you should NEVER let them touch your rv for any reason!

vsheetz · 05-21-2018, 06:17 PM

You need a controller. And a different guy to design and install your solar system.

4x4 · 05-21-2018, 06:32 PM

You need a new installer. Also do NOT put on flexible solar panels. They are terrible for an RV. There are many reasons to not install flexible panels not the least is heat build up on the roof. I had 6 of them for 5 months and pulled them off to put on regular stiff panels.