Solar setup???

[Toothpick]

Never mind I think I found the answer to my question... If I use 4 100 watt panels looks like I'll need at least a 40 amp controller....

[kcmusa]

Originally Posted by mele

Ok.... Now if I want to upgrade will a 20 amp mppt controller be large enough for 4 100 watt panels in a series-parallel?

NO
12v 100W = 8.33333 amps x4 33.3333 amps
thats best case, you will get less but you need at least a 30 amp controller

[WolfWhistle]

Before planning anything regarding solar charging, the first thing to do is to determine how many watts are going to be used and thus how many has to be put back into the batteries. To be talking 100W... 200W... 400W panels first is backward thinking.

First thing is to get and install is a Trimetric battery monitor. Get those numbers and plan properly.

I would suggest getting informed and this is an excellent source for information. WW

https://handybobsolar.wordpress.com/...ging-puzzle-2/

[Toothpick]

Originally Posted by WolfWhistle

Before planning anything regarding solar charging, the first thing to do is to determine how many watts are going to be used and thus how many has to be put back into the batteries. To be talking 100W... 200W... 400W panels first is backward thinking.

First thing is to get and install is a Trimetric battery monitor. Get those numbers and plan properly.

I would suggest getting informed and this is an excellent source for information. WW

https://handybobsolar.wordpress.com/...ging-puzzle-2/

Thanks, I know.

I'm just thinking out loud on the forum about upgrading later. IF I decide to go from just a battery maintenance setup to full off the grid for my TH.

Mel

[Toothpick]

Starter Kit came in today. Now to got hook it up!

[Toothpick]

OK.

My test results from today. Tested with a hand held voltage meter.
My TH is currently on the north side of a strip of Live Oak Trees.

I got from 12.2 to 12.4 volts in direct diffused sunlight (real bright overcast/high clouds) or diffused shade (no real dark shadows sun broken up by high near leafless trees).

I got 12.5 - 12.6 volts sitting on the tailgate of my truck (white) in same general area. So reflected bright light seemed to increase voltage a little. Maybe the white roof on TH will help?

Think I'm going to order a 30A Mppt Controller and two more panels.
If I install them in Series and get near 36V I should have enough juice to keep two group 24 batteries up during the week and run lights, TV and heater on the weekend...

Thanks for everyone's input.

Mel

[WolfWhistle]

Originally Posted by mele

OK.

My test results from today. Tested with a hand held voltage meter.
My TH is currently on the north side of a strip of Live Oak Trees.

I got from 12.2 to 12.4 volts in direct diffused sunlight (real bright overcast/high clouds) or diffused shade (no real dark shadows sun broken up by high near leafless trees).

I got 12.5 - 12.6 volts sitting on the tailgate of my truck (white) in same general area. So reflected bright light seemed to increase voltage a little. Maybe the white roof on TH will help?

Think I'm going to order a 30A Mppt Controller and two more panels.
If I install them in Series and get near 36V I should have enough juice to keep two group 24 batteries up during the week and run lights, TV and heater on the weekend...

Thanks for everyone's input.

Mel

12 volt panels go in parallel to match the 12 volt charger controller and batteries you have. Not sure how you are measuring them, but if properly tilted they should give you more on a sunny day. Like I said way back, you cannot have any shadow fall on a panel or it will basically give you nothing. You need to study more on solar but in the meantime don't connect panels in series. WW
WW

[boondocking]

If you are getting an MPPT controller you can connect the panels in series up to the maximum input voltage of the controller.
The one adavantage to connecting in parallel is if a panel is in shade it will not bring down the voltage as much compared to being connected in series.

[WolfWhistle]

The combined battery voltage has to be up as well ... not to mention appliances, pumps, lights etc etc. The higher DC voltage setups are for other than RVs. IMO
WW

[WolfWhistle]

I wouldn't waste my money on an MPPT controller... for an RV

[pgandw]

You need at least 13.2V from the controller to charge a battery. A fully charged battery will register 12.6 - 12.7V at rest.

Fred W

[boondocking]

Originally Posted by WolfWhistle

The combined battery voltage has to be up as well ... not to mention appliances, pumps, lights etc etc. The higher DC voltage setups are for other than RVs. IMO
WW

Oh oh, I guess that electrical components and batterys in my trailer weren't told that they need to be of a higher voltage to coup with the 36 vdc from my solar panels.

Wow, you have really been mis-informed.
There is no need to have higher voltage batterys, pumps, lights etc etc.

An MPPT controller will take an input voltage of say 80 volts dc at 6 amps and converter that to an output of 13 volts dc at 36 amps.

[Blackhat6mike]

Originally Posted by mele

What i'm really asking is can I connect both the trailer shore power/converter and the solar controller directly to my battery bank without any cutoff or shunt?

Mel

Yes

[Blackhat6mike]

Originally Posted by mele

OK.

My test results from today. Tested with a hand held voltage meter.
My TH is currently on the north side of a strip of Live Oak Trees.

I got from 12.2 to 12.4 volts in direct diffused sunlight (real bright overcast/high clouds) or diffused shade (no real dark shadows sun broken up by high near leafless trees).

I got 12.5 - 12.6 volts sitting on the tailgate of my truck (white) in same general area. So reflected bright light seemed to increase voltage a little. Maybe the white roof on TH will help?


Think I'm going to order a 30A Mppt Controller and two more panels.
If I install them in Series and get near 36V I should have enough juice to keep two group 24 batteries up during the week and run lights, TV and heater on the weekend...

Thanks for everyone's input.

Mel

In full sunlight with 3 x 100 watt panels in series, you have a potential for ~64 vdc [22 vdc per panel] and 5.75 amps. You will never see that much unless you live in the south and see full sun.
Absolutely get an MPPT controller. Unless your TV is 12vdc, you will need an inverter to watch it.

[Blackhat6mike]

Originally Posted by boondocking

Oh oh, I guess that electrical components and batterys in my trailer weren't told that they need to be of a higher voltage to coup with the 36 vdc from my solar panels.

Wow, you have really been mis-informed.
There is no need to have higher voltage batterys, pumps, lights etc etc.

An MPPT controller will take an input voltage of say 80 volts dc at 6 amps and converter that to an output of 13 volts dc at 36 amps.

X2 The controller regulates the incoming vdc from the panels and sends it out to the batteries at the proper voltage. Just don't exceed the max INPUT voltage of the controller. The controller automatically senses your batteries voltage.

[Toothpick]

OK... It looks like I got the bug....

Finally figured out where to run my PV and battery wires and mount my controller. Going to run the PV wires right down the center of the awning mount where the existing power owning wires run. Its only a couple feet from there to where my battery wires go into the floor to the battery switch, common ground bar and converter.

Just ordered a 40Amp Mttp controller from Regony and another 100W Mono Panel.

My goal is to have 4 100w panels by Bike Week in March. I may or may not upgrade to two high amp 6v batteries.

That way we can dry camp and just use the batteries for water pump, lights, a little TV and maybe the heater fan at night (Depends on temps at Daytona in March...).

[Toothpick]

If I connect my positive wire from my controller to the battery side of my cutoff switch and the negative wire to the common neg ground on my TT will this work?

Thanks,

Mel

[A32Deuce]

I connected positive to positive on bat. and negative to negative on bat. Works fine. Copied instructions with my controller.

[Flybob]

I always recommend that you get at least 50% higher capacity controller than you think you will need. In the majority of the cases, people feel the need to add more panels down the road which requires a larger controller purchase. It is much less expensive to buy a higher capacity controller than to buy two.

[mud yapster]

You should use fuses in line with the solar panels for safety and to disconnect them from the circuitry.
I have 520 watts of solar and a Morningstar 60amp charge controller tied to 12v AGM 435ah battery bank feeding my 2000 watt inverter with transfer switches, fusing, ect... You can see pics on my profile page.
I boondock anywhere anytime.