Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
Old 06-22-2021, 06:43 AM   #1
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
Charging voltage and solar panel connection.

Greetings! Can somebody answer my question, please. I have a CNLINKO 2 Pin Power Industrial Circular Socket Connector on the side on my RV by the door and a label saying solar ready. However no more explanation anywhere. Is this a place where I should plug a solar panel controller, or I should plug my solar panel there straight with no controller? My current setup is portable solar panel, 50' of a heavy gauge soft flexible cable, controller, and then to that socket on the RV's side. It seems to work fine, but I'm not sure if it's right and if by removing controller I'll not gain some power from this setup. Also, when solar panel charging my house batteries I see charging voltage 14.4V dropping to 13.6V (at this point current drops to 1.2A or so), so it's float charging. If I drive my RV charging voltage stays 14.4V as long as I drive, even if it's 10 hours straight. However, if I run onboard generator or hook to the shore power I see 13.6V no matter how low/full the batteries are. Any idea what's going on? I started asking myself these questions after my batteries had to be replaced after only 4 years of service. I used to have a sailboat for 17 years and did a lot of long sails (100-120 hours no shore power) and I always had at least 6 years out of same deep cycle batteries. I used a little Honda 1000Wt generator to rechage my batteries out at sea. Thanks!
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-22-2021, 07:35 AM   #2
Senior Member
 
PhilFromMaine's Avatar
 
Join Date: Sep 2020
Location: Maine
Posts: 1,506
A lot of questions all in one paragraph is hard for these old eyes and brain to process. Pertaining to solar controllers (SC), you should always use one to protect your batteries.

A SC supplies current at a rate your batteries can safely absorb. If you are using your side port, it is fairly easy to fit one in on the solar cable from the panel.
PhilFromMaine is offline   Reply With Quote
Old 06-22-2021, 08:07 AM   #3
Senior Member
 
Chuck_S's Avatar
 
Join Date: Aug 2018
Location: Richmond VA
Posts: 4,515
The voltage regulator in your truck operates on a different algorithm than a solar charger or the charger built into your trailer's power center. The trailer's power center is expected to supply large amounts of power to charge low batteries. Truck voltage regulator only has to provide enough voltage to trickle charge the starting battery and operate the entire 12v system in the truck. It's designed to prevent overcharging the battery which used very little power to start the truck.

How little power you ask? Assume the starter pulls 600 amps and you run it for 6 seconds. 3600 amp-seconds = 60 amp-minutes = 1 amp hour. One (1)! Pretty easy to put this back. Since the truck voltage regulator is really only designed to do this it should not be a big surprise it takes forever for it to recharge dead trailer batteries at the end of a long wire where the voltage has dropped.

-- Chuck
__________________
2006 Roo 23SS behind a 2017 Ford Expedition
Chuck_S is offline   Reply With Quote
Old 06-22-2021, 01:00 PM   #4
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
[QUOTE=Chuck_S;2583101]The voltage regulator in your truck operates on a different algorithm than a solar charger or the charger built into your trailer's power center.

Thanks for your reply. That's right. That's why the house batteries should see not the same charge schedule as starting battery, right? But in my case house batteries are getting the same voltage as starting battery. It looks to me as when I'm driving I'm getting charge on house batteries exactly the same as on my chassis' battery and that is my concern.

Algorithm may be different, but outcome to the batteries should be the same in order not to prematurely destroy them, right?

Also I do not have a trailer, that's a class C unit.
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-22-2021, 02:02 PM   #5
Senior Member
 
Join Date: Jul 2017
Location: North of Seattle, WA
Posts: 17,283
If starting battery and house batteries are connected in parallel, terminal to terminal, the alternator's algorithm will see them as a single battery.

Resistance in connecting wires will be a factor but it's highly likely that those seeing only trickle charges from TV or Coach alternators are seeing the effect of improper wiring of auxiliary battery and Smart Alternator.
__________________
"A wise man can change his mind. A fool never will." (Japanese Proverb)

"You only grow old when you run out of new things to do"

2018 Flagstaff Micro Lite 25BDS
2023 f-150 SCREW XLT 3.5 Ecoboost (The result of a $68,000 oil change)
TitanMike is offline   Reply With Quote
Old 06-22-2021, 02:16 PM   #6
Senior Member
 
Chuck_S's Avatar
 
Join Date: Aug 2018
Location: Richmond VA
Posts: 4,515
Your vehicle alternator will supply charging current to both batteries but is limited by the voltage regulator algorithm that is optimized for the starting battery. Shore power thru the power panel's battery charger should have a more optimal algorithm for the house batteries. And there are rather expensive alternators optimized for both tasks.

The long, small wire power cable from the alternator to a trailer results in some significant voltage drop not present in the short, thick cables in motorhomes.

-- Chuck
__________________
2006 Roo 23SS behind a 2017 Ford Expedition
Chuck_S is offline   Reply With Quote
Old 06-22-2021, 02:45 PM   #7
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
Quote:
Originally Posted by Chuck_S View Post
Your vehicle alternator will supply charging current to both batteries but is limited by the voltage regulator algorithm that is optimized for the starting battery. Shore power thru the power panel's battery charger should have a more optimal algorithm for the house batteries. And there are rather expensive alternators optimized for both tasks.

The long, small wire power cable from the alternator to a trailer results in some significant voltage drop not present in the short, thick cables in motorhomes.

-- Chuck

I guess you are still missing the point that I'm not talking about a trailer. This is a class C unit.

The main problem is that there is no any kind of electrical schematic was supplied with this RV from the dealership. So I have no way to know how it's wired, connected, and what components are there.
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-22-2021, 03:08 PM   #8
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
Quote:
Originally Posted by Chuck_S View Post
Your vehicle alternator will supply charging current to both batteries but is limited by the voltage regulator algorithm that is optimized for the starting battery. Shore power thru the power panel's battery charger should have a more optimal algorithm for the house batteries. And there are rather expensive alternators optimized for both tasks.

The long, small wire power cable from the alternator to a trailer results in some significant voltage drop not present in the short, thick cables in motorhomes.

-- Chuck
First of all once again it's not a trailer, but a class C unit, motorhome.

My main problem is that there is no any kind of electrical schematic supplied with this RV from the dealership. So I have no way to know how it's wired, connected, and what components are there. And the voltages I mentioned in original post do not make sense to me. So I was trying to get some explanation from the people what may know more about it.
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-22-2021, 05:11 PM   #9
Senior Member
 
Chuck_S's Avatar
 
Join Date: Aug 2018
Location: Richmond VA
Posts: 4,515
Who cares what the vehicle it is? Trailer or Class C or bus chassis Motorhome are all charging their batteries off the vehicle's alternator. Nothing special about what you got, it all works the same way.

-- Chuck
__________________
2006 Roo 23SS behind a 2017 Ford Expedition
Chuck_S is offline   Reply With Quote
Old 06-22-2021, 05:24 PM   #10
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
Quote:
Originally Posted by Chuck_S View Post
Who cares what the vehicle it is? Trailer or Class C or bus chassis Motorhome are all charging their batteries off the vehicle's alternator. Nothing special about what you got, it all works the same way.

-- Chuck
Alternator give out AC, but to charge battery you need DC. DC creates much more loss in the wiring. So 30' to the trailer or 3' to the house battery in motorhome makes some difference. It seems to be clear for me.
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-22-2021, 05:53 PM   #11
Senior Member
 
Join Date: Sep 2020
Posts: 734
That solar port on the side is most likely directly connected to the house battery. If you are hooking a panel up that way, it needs to have a built-in controller or you need to add one before the port or you will cook your battery(ies). Solar panels often output 20-21v nominal and that needs to be regulated by a controller to the maximum voltage for your house battery type.

So you need to check your panel and see if it has a controller built in. If so, you don't need to use the separate one your mention.
__________________
2021 Flagstaff 21DS
2015 Silverado 2500HD (overkill but convenient)

Renogy bits: 3000W Inverter/Charger, 400Ah LiFePo4, 40A DC-to-DC
Rich Solar bits: 400W of panels, 40A MPPT
Misc bits: LevelMatePro+, SolidRemote based wireless controlled LED storage lighting
jbflag21ds is offline   Reply With Quote
Old 06-22-2021, 05:57 PM   #12
Member
 
Join Date: Sep 2017
Location: Round Lake, IL, USA
Posts: 74
Quote:
Originally Posted by jbflag21ds View Post
That solar port on the side is most likely directly connected to the house battery. If you are hooking a panel up that way, it needs to have a built-in controller or you need to add one before the port or you will cook your battery(ies). Solar panels often output 20-21v nominal and that needs to be regulated by a controller to the maximum voltage for your house battery type.

So you need to check your panel and see if it has a controller built in. If so, you don't need to use the separate one your mention.
That's what I guessed, but thought somebody knows for sure.
__________________
Severin & Ellen
1991 Westfalia Vanagon GL full camper
1997 Eurovan full camper
1984 Catalina 36 hull 268 (sailboat)
2017 Coachmen Freelander Micro 20CB
Ford Transit 350 HD cutaway chassis.
C36hull268 is offline   Reply With Quote
Old 06-23-2021, 08:46 PM   #13
Senior Member
 
camaraderie's Avatar
 
Join Date: Feb 2014
Posts: 2,832
Man theres a lot of misinfo on this thread.
First...solar ready usually means you plug in your panel and a cheap controller steps down the voltage to 13.6 or so and there's no multistage charging...just an increasing resistance to CURRENT flow as the battery comes up to full charge. Usually a full sized panel will put out in the 17.9V range which would otherwise be dangerous to your system. The problem with an old fashioned controller is that the energy from 17.9 stepping down to 13.6V is wasted in heat. In the old days...my controller had a shunt from the controller to the water heater to warm the water up all day! These days...more sophisticated PCM/MPPT controllers make much better use of that excess energy and put it into your batteries giving about a 10% improvement per day in amp hours recovered. You can double check the output of the panel and existence of a controller easily with a volt meter, As long as your seeing less than 15V...at the batteries with everything disconnected except the panels...you can assume you have a controller...and you'll probably be seeing 13.6-14.3 or so.
Your alternator will almost surely put out 13.6v all day long... again...resistance to current as the house battery is charged will grow and current will slow to a trickle once fully charged but voltage will remain at 13.6V as long as the engine is running.
You probably have a black box called a Battery control center somewhere close to your batteries...it has controlling circuitry and solenoids to tell incoming current where to go and when. Many different types but here is what a common one looks likel
Attached Thumbnails
Click image for larger version

Name:	bcc.JPG
Views:	37
Size:	73.4 KB
ID:	257719  
__________________
________
Cam
2015 Georgetown 280DS
2019 Vespa Primavera 150's (pair)
camaraderie is offline   Reply With Quote
Reply

Tags
charging, panel, solar, solar panel, voltage

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 04:11 AM.