Recent Topics
How do I update my profile?
by ernied - 09/15/19 07:07 AM
Most dangerous job ever?
by Mad_Hatter - 09/15/19 07:06 AM
04 Grand Marquis
by mrjlube - 09/15/19 07:01 AM
Engine burning oil
by Espada - 09/15/19 06:49 AM
Walmart near me do not sell havoline oil
by MetalSlug - 09/15/19 04:11 AM
Wanted: Inexpensive car
by FirstNissan - 09/15/19 02:53 AM
Do all replacement LED headlight bulbs suck?
by Nick1994 - 09/15/19 12:56 AM
5 qt Chevron Supreme 5w-30 for $12.42 @ walmart.com
by gallydif - 09/15/19 12:03 AM
how effective is spray scotchgard?
by WhyMe - 09/14/19 11:39 PM
Want opinion of disc brake pad wear
by boulderdentist - 09/14/19 11:08 PM
Mercedes’ dealer oil filter panel/board
by SlavaB - 09/14/19 11:08 PM
Mercedes damage code
by SlavaB - 09/14/19 11:00 PM
Restoring the paint on the Crown Vic
by Colt45ws - 09/14/19 10:39 PM
Hyundai Ioniq
by WhyMe - 09/14/19 10:08 PM
Grooves in windshield due to wiper blades
by dx92beater - 09/14/19 09:43 PM
Valvoline Advanced Heavy-duty Oil Stabilizer
by Toh1 - 09/14/19 09:08 PM
The joys of air filters and the desert.
by Chris142 - 09/14/19 08:36 PM
Havoline Conventional 5qt $12.99 Menards
by Warstud - 09/14/19 08:12 PM
Newest Members
KevATL, DragSGT, Gbenitez, DoctorPc, FarmerDan
69277 Registered Users
Who's Online Now
79 registered members (2015_PSD, 4WD, Astro_Guy, atikovi, avi1777, aba4430, 8 invisible), 1,210 guests, and 25 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics294,559
Posts5,062,352
Members69,276
Most Online3,532
Jul 30th, 2019
Donate to BITOG
Print Thread
Hop To
Solar panel with charge controller. #5081053 04/20/19 06:38 PM
Joined: May 2010
Posts: 10,453
S
spasm3 Online Happy OP
OP Online Happy
S
Joined: May 2010
Posts: 10,453
I have talked about this before, a few years ago. I have a new travel trailer that comes with a solar charge port. Its a 10 amp port with a 7.5 amp fuse. This seems to go right into the battery circuit with no charge controller, so a simple solar panel would not be isolated at night. So what would be a good panel and charger controller. I keep my trailer in a shed some 100 feet from the house. the shed is in full sun. I think a 50w panel would be enough at 3-4 amps to keep the battery charged.

Any suggestions? The shed is a metal shed 24ft wide by 41 feet open on each end so the charge controller would need to be water proof.

I can get a plug to fit the port on my camper. it looks like this. Anyone else run a solar panel to keep the battery charged?

[Linked Image]

[Linked Image]


13 elantra 78k 5w30 synpwr
03 chevy avalanche 83k synpwr 5w30
17 mazda cx-5 12300 miles m1 0w30
Re: Solar panel with charge controller. [Re: spasm3] #5081072 04/20/19 06:55 PM
Joined: May 2014
Posts: 1,696
P
philipp10 Offline
Offline
P
Joined: May 2014
Posts: 1,696
on a continual basis it shouldn't take anywhere near 3-4 amp to keep a battery charged....should it?

Re: Solar panel with charge controller. [Re: spasm3] #5081116 04/20/19 07:37 PM
Joined: Dec 2016
Posts: 9,419
L
Linctex Offline
Offline
L
Joined: Dec 2016
Posts: 9,419
A 10 to 25 watt panel will easily keep your RV battery topped off - as long as there's no continual draw.

If the fridge is left on all the time - 300 or more watts will be needed.

For just keeping the battery topped off, I think something like this would be great for you:

https://www.amazon.com/Morningstar-Guard-4-5A-solar-controller/dp/B0012N4SZW/ref=sxin_2_ac_d_pm


"The evidence demands a verdict".
(Re:VOA)"it's nearly impossible to actually know the particular additives that are in there at what concentrations."
Re: Solar panel with charge controller. [Re: spasm3] #5081117 04/20/19 07:39 PM
Joined: Dec 2016
Posts: 9,419
L
Linctex Offline
Offline
L
Joined: Dec 2016
Posts: 9,419


"The evidence demands a verdict".
(Re:VOA)"it's nearly impossible to actually know the particular additives that are in there at what concentrations."
Re: Solar panel with charge controller. [Re: spasm3] #5081156 04/20/19 08:26 PM
Joined: Oct 2010
Posts: 1,917
W
wrcsixeight Offline
Offline
W
Joined: Oct 2010
Posts: 1,917
I have the controller linked above.

Avoid. The wire entry screws are basically one time use. I.stripped.mine with jewellers screwdriver.

The interface is clunky. Ridiculous. . It will limit voltage. But choosing
/changing this voltage is nightmare.

The USB ports.overload above 0.62Amps.

It will simply seek one voltage and hold it there. 14.4v from mid morning all day long every day will overcharge.


LA 318 Roller Cam
Pennzoil Platinum 10w-30 HM
Fram ultra XG8A
Fram Ultra XG16 on remote transmission filter mount
Re: Solar panel with charge controller. [Re: spasm3] #5081500 04/21/19 09:04 AM
Joined: Jun 2011
Posts: 1,605
W
wag123 Online Content
Online Content
W
Joined: Jun 2011
Posts: 1,605
You just need a simple PWM charge controller. It should be rated at at least double the amps that you will need because 99% of them are manufactured in China and many products coming from there have inaccurate/overrated specs. A 10 amp controller would be appropriate if using a 50 watt solar panel. Also, if the controller will be outside in the elements it will need to be waterproof, like this one... https://www.amazon.com/dp/B07315CF47. FYI, MOST charge controllers are NOT waterproof.
A 50 watt panel would be appropriate for this application. You should not go lower because it will not often produce the full 50 watts. The system with controller is only about 85-90% efficient (at best, in full mid-day sun), and lower on long wire runs. Also, the solar panel output will diminish over time. Monocrystalline solar panels degrade less than polycrystalline solar panels over time (they are also more efficient).
One other piece of advice, don't cheap-out on the wire. You are going to need a fairly large gauge wire if there will be any appreciable distance between the solar components and the trailer, think 12 gauge copper at 50-75 feet (larger gauge if using copper clad aluminum wire). Smaller gauge wire will carry the 4 amp load, but the higher resistance causes a rather large voltage drop in DC current systems.

Re: Solar panel with charge controller. [Re: spasm3] #5082532 04/22/19 09:12 AM
Joined: Feb 2007
Posts: 4,044
M
meep Offline
Offline
M
Joined: Feb 2007
Posts: 4,044
If you're using a small panel, like a 10 watt panel, no charge controller is needed, just a blocking diode. A 10 watt panel won't produce enough overcharge to stress a battery. That's a maintainer. If you want something that can allow you to to occasionally run lights and accessories without ever plugging it in, you'll need a fullsize panel and the controller.


2018 F150
2015 crv (wifey!)
Re: Solar panel with charge controller. [Re: spasm3] #5082774 04/22/19 01:41 PM
Joined: Oct 2010
Posts: 1,917
W
wrcsixeight Offline
Offline
W
Joined: Oct 2010
Posts: 1,917
10 watts of.solar panel can easily overcharge some batteries. The no charge charge controller advice might or.might not be valid depending on the battery., Capability of hot solar panel through glass. And parasitic loads. As well as the state of charge of the battery when solar panelstarts producing.

Lots off dried up failed batteries out there because.of.unregulated.small solar panels whose.owners were.told no controller was needed. It's just not true in All cases. Too many variables.


LA 318 Roller Cam
Pennzoil Platinum 10w-30 HM
Fram ultra XG8A
Fram Ultra XG16 on remote transmission filter mount
Re: Solar panel with charge controller. [Re: wrcsixeight] #5082977 04/22/19 05:06 PM
Joined: Feb 2007
Posts: 1,286
A
Anduril Offline
Offline
A
Joined: Feb 2007
Posts: 1,286
Originally Posted by wrcsixeight
I have the controller linked above.

Avoid. The wire entry screws are basically one time use. I.stripped.mine with jewellers screwdriver.

The interface is clunky. Ridiculous. . It will limit voltage. But choosing
/changing this voltage is nightmare.

The USB ports.overload above 0.62Amps.

It will simply seek one voltage and hold it there. 14.4v from mid morning all day long every day will overcharge.

I had one of those that was defective from the get-go. Voltage went above 15 and never dropped.


2015 Nissan Versa Note 1.6/5MT
2012 Toyota Tacoma 2.7/4AT
2007 Toyota Camry 2.4/5AT
2005 Nissan XTerra 4x4 4.0/6MT
2002 Mustang GT Convertible 4.6/5MT
2009 Kawasaki Vulcan 900
2013 Hyosung ST7
Re: Solar panel with charge controller. [Re: wrcsixeight] #5083499 04/23/19 08:14 AM
Joined: Feb 2007
Posts: 4,044
M
meep Offline
Offline
M
Joined: Feb 2007
Posts: 4,044
Originally Posted by wrcsixeight
10 watts of.solar panel can easily overcharge some batteries. The no charge charge controller advice might or.might not be valid depending on the battery., Capability of hot solar panel through glass. And parasitic loads. As well as the state of charge of the battery when solar panelstarts producing.

Lots off dried up failed batteries out there because.of.unregulated.small solar panels whose.owners were.told no controller was needed. It's just not true in All cases. Too many variables.


can't argue with that- though in my experience a 10W panel doesn't truly output 10 Watts at 12V. Open circuit they'll put out 18-20V, and at a short circuit they'll put out 0.75-1 amps, and into a 12V load they'll put out maybe half an amp. Into a 14V battery and a through a blocking diode (0.7V loss, so it looks like a 14.7V battery or 3.3V difference), the current quickly tapers to a quarter amp or less. For that reason I won't even bother with something that small.

On our travel trailer I installed a 150W 2'x4' panel with a 15amp (?) charge controller. the weak spot for so many of the controllers is that the SCRs/xFETs used aren't properly cooled. In mine they "hope" that once the back plate is screwed on that the angle of the devices press their backs to the aluminum back plate for thermal transfer. Short of installing heat sinks and a different rear casing, I re-bent mine and liberally applied a gooey silicone thermal grease (not paste like CPU coolers use, the grease flows easier). It's been working now for 3-4 years, with a daily load, as the controller also turns on the porch light at sundown nightly for a few hours. For rough math, that 150W panel seems to be good for about maybe 4-5 amps tops into 12V during peak sun.


So all in all, the wattage rating has been a little misleading for PV in my experience.


2018 F150
2015 crv (wifey!)
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™