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

Go Back   iRV2 Forums > CAMPING, TRAVEL and TRIP PLANNING > Boondocking
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 05-15-2022, 08:23 AM   #1
Member
 
Join Date: Feb 2020
Location: Bristol, Vermont
Posts: 46
Solar Question New install

I have 5 -200w solar panels and a Victron Charge controller. Does anyone know what I should be expecting to see on my Victron App for Amps at 12 volts lets sat at 12:00 noon on sunny day. Im attached to 8-100 amp Battleborn batteries. Perhaps I won't see much on the app if my batteries don't need a charge or perhaps I have an issue in my connections but I don't seem to get much.
__________________
Mark Hamblin
Vermont
Hambones is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-15-2022, 08:56 AM   #2
Senior Member
 
Join Date: Oct 2017
Location: Courtenay BC
Posts: 129
hook an electric heater up for about 20/30 minutes and run your batteries down a bit should see the draw down and input on your controller with my setup i am seeing about 55 volts coming in from the panels and up to 40 amps 12 volt going to the batteries 2 strings of 3 series and then paralled for about 800 watts
Reka is offline   Reply With Quote
Old 05-15-2022, 09:13 AM   #3
Senior Member
 
SteveJ.'s Avatar
 
Join Date: Dec 2019
Location: America's Seaplane City.
Posts: 736
Quote:
Originally Posted by Hambones View Post
I have 5 -200w solar panels and a Victron Charge controller. Does anyone know what I should be expecting to see on my Victron App for Amps at 12 volts lets sat at 12:00 noon on sunny day. Im attached to 8-100 amp Battleborn batteries. Perhaps I won't see much on the app if my batteries don't need a charge or perhaps I have an issue in my connections but I don't seem to get much.
How are the 5 panels wired and what is the wire size running to the controller and then to the batteries? Which controller fo you have, model number? As mentioned earlier do some discharging on the batteries to create an electrical demand.
__________________
1998 Safari Trek 2480, 7.4 Vortec
'15 Kawasaki Versys650LT, well farkled
Mid Flowriduh
SteveJ. is offline   Reply With Quote
Old 05-15-2022, 09:44 AM   #4
Senior Member
 
paul65k's Avatar


 
Alpine Owners Club
Join Date: Nov 2015
Location: Lake Havasu City, AZ
Posts: 2,636
Quote:
Originally Posted by SteveJ. View Post
How are the 5 panels wired and what is the wire size running to the controller and then to the batteries? Which controller fo you have, model number? As mentioned earlier do some discharging on the batteries to create an electrical demand.
With 5 panels your only real option is to wire them in parallel. I'm guessing that you have the Victron 150/85 controller??

Based on the Victron configuration tool you can expect somewhere between 75.3 to 86.8 Amps (based on temp) at 100% efficiency, which will never happen. You also have to consider any line loss based on your wire size, it will be even more critical based on the low voltage that will be created by only being able to wire these in parallel (odd number of panels).

You may be better served to go to 1200W (6 panels) and wire them 3Series - 2 Parallel. This will keep the voltage higher and will minimize line loss and allow a smaller wire size between combiner box and your solar controller.
__________________
Paul & Jean
2001 Alpine 36FDDS (74291)-1600W Solar, 13,440Wh (525Ah @24V) LiFePO4
2019 Jeep Grand Cherokee Trailhawk (Hemi)
2006 Alpenlite 32RL - Sold
paul65k is offline   Reply With Quote
Old 05-15-2022, 09:59 AM   #5
Senior Member
 
SteveJ.'s Avatar
 
Join Date: Dec 2019
Location: America's Seaplane City.
Posts: 736
Quote:
Originally Posted by paul65k View Post
With 5 panels your only real option is to wire them in parallel. I'm guessing that you have the Victron 150/85 controller??

Based on the Victron configuration tool you can expect somewhere between 75.3 to 86.8 Amps (based on temp) at 100% efficiency, which will never happen. You also have to consider any line loss based on your wire size, it will be even more critical based on the low voltage that will be created by only being able to wire these in parallel (odd number of panels).

You may be better served to go to 1200W (6 panels) and wire them 3Series - 2 Parallel. This will keep the voltage higher and will minimize line loss and allow a smaller wire size between combiner box and your solar controller.
Good thoughts. I was heading in that direction. I would wonder at the size of wires needed to carry that much current without too much voltage drop.

Without know specifics I would think even 2S2P with 4 panels into an MPPT controller would be better than what is apparently the setup now.
__________________
1998 Safari Trek 2480, 7.4 Vortec
'15 Kawasaki Versys650LT, well farkled
Mid Flowriduh
SteveJ. is offline   Reply With Quote
Old 05-16-2022, 01:35 AM   #6
Member
 
Join Date: Feb 2020
Location: Bristol, Vermont
Posts: 46
Thank you all

Ill let my batteries die down and see what I get. Never let (or had the need to) them get down lower than 80%.
__________________
Mark Hamblin
Vermont
Hambones is offline   Reply With Quote
Old 05-16-2022, 05:51 AM   #7
Senior Member
 
paul65k's Avatar


 
Alpine Owners Club
Join Date: Nov 2015
Location: Lake Havasu City, AZ
Posts: 2,636
Quote:
Originally Posted by SteveJ. View Post
Good thoughts. I was heading in that direction. I would wonder at the size of wires needed to carry that much current without too much voltage drop.

Without know specifics I would think even 2S2P with 4 panels into an MPPT controller would be better than what is apparently the setup now.
Yes I agree that would be a good solution as long as you have enough panels to do what you need to do.

One thing I have discovered in real life is that your output is probably only going to be ~70-75% of the rating in most real-world situations.

I highly recommend you over-panel by at least 120% of what you think you will actually be needing for your uses.

Good luck!
__________________
Paul & Jean
2001 Alpine 36FDDS (74291)-1600W Solar, 13,440Wh (525Ah @24V) LiFePO4
2019 Jeep Grand Cherokee Trailhawk (Hemi)
2006 Alpenlite 32RL - Sold
paul65k is offline   Reply With Quote
Old 05-16-2022, 03:22 PM   #8
Member
 
Join Date: Feb 2020
Location: Bristol, Vermont
Posts: 46
Quote:
Originally Posted by SteveJ. View Post
Good thoughts. I was heading in that direction. I would wonder at the size of wires needed to carry that much current without too much voltage drop.

Without know specifics I would think even 2S2P with 4 panels into an MPPT controller would be better than what is apparently the setup now.
My panels are wired in series giving me 60 volts with 11 ft of # 6 wire from the roof the the Charge controller. The controller is a Victron MPPT 150/100 (good for 150 volts and 100 amps) From the controller to the disconnect and then to the batteries is 3' of # 6 wire. My 8 batteries are wired together in parallel with 4/0 and 2/0 to my Battery disconnect and then to the inverter. Battleborn say this is all good.

My panels should produce 16.67 amps each (on a perfect day) so I feel as if i should be sending 60-70 amps (realistically) out of my controller if my batteries need it.

Im just not sure what I would see on my Vicron App if my batteries are in a fully or near fully charge state. No one ever told me that. Should I still see what the panels are producing even if I'm not using it? Guess I wasn't near a up on this as I thought.
__________________
Mark Hamblin
Vermont
Hambones is offline   Reply With Quote
Old 05-16-2022, 05:27 PM   #9
Senior Member
 
SteveJ.'s Avatar
 
Join Date: Dec 2019
Location: America's Seaplane City.
Posts: 736
Quote:
Originally Posted by Hambones View Post
My panels are wired in series giving me 60 volts with 11 ft of # 6 wire from the roof the the Charge controller. The controller is a Victron MPPT 150/100 (good for 150 volts and 100 amps) From the controller to the disconnect and then to the batteries is 3' of # 6 wire. My 8 batteries are wired together in parallel with 4/0 and 2/0 to my Battery disconnect and then to the inverter. Battleborn say this is all good.

My panels should produce 16.67 amps each (on a perfect day) so I feel as if i should be sending 60-70 amps (realistically) out of my controller if my batteries need it.

Im just not sure what I would see on my Vicron App if my batteries are in a fully or near fully charge state. No one ever told me that. Should I still see what the panels are producing even if I'm not using it? Guess I wasn't near a up on this as I thought.
You will see the power coming from the panels reduce as the batteries get full. Normal operation. If you fire up something on the 12 volt side you should see an immediate increase in watts coming from the panels, assuming that there is enough solar to provide it.
__________________
1998 Safari Trek 2480, 7.4 Vortec
'15 Kawasaki Versys650LT, well farkled
Mid Flowriduh
SteveJ. is offline   Reply With Quote
Old 05-17-2022, 06:00 AM   #10
Member
 
Join Date: Feb 2020
Location: Bristol, Vermont
Posts: 46
Quote:
Originally Posted by SteveJ. View Post
You will see the power coming from the panels reduce as the batteries get full. Normal operation. If you fire up something on the 12 volt side you should see an immediate increase in watts coming from the panels, assuming that there is enough solar to provide it.
Thank you Steve. I guess I need to use some battery up and see where I stand. Just though I would see on the charge controller how much solar I had available if I needed It but I guess thats not how it works. It does say I have 80+ volts but very little amps. Ill run the batteries down today as the sun is out again and see where I stand.
__________________
Mark Hamblin
Vermont
Hambones is offline   Reply With Quote
Old 05-21-2022, 11:25 AM   #11
Member
 
Join Date: Mar 2022
Posts: 63
Yes, you can only measure amps when the charge controller is supplying full amps.
Panels will be able to supply full amperage, but the controller will only supply what the batteries need, so using a high-amp appliance such as a heater can force the controller to give max amps so you can see the numbers.

Amps is really a measurement of what you are using from the power source (solar panels), not what the system can do.
Bobertgoes is offline   Reply With Quote
Old 06-25-2022, 07:32 AM   #12
Junior Member
 
Join Date: May 2016
Posts: 22
Quote:
Originally Posted by paul65k View Post
Yes I agree that would be a good solution as long as you have enough panels to do what you need to do.

One thing I have discovered in real life is that your output is probably only going to be ~70-75% of the rating in most real-world situations.

I highly recommend you over-panel by at least 120% of what you think you will actually be needing for your uses.

Good luck!
Good information so far. My problem is figuring out how much I think I will be needing, so I can determine if solar is for us. My Vista runs on 30 amp service, I have an Onan Quiet (haha) 4000 generator, a single 13500 A/C, and a 900W microwave, most else is trivial I think. For the first time since we bought the motorhome, I expect lots of boondocking possibly for 3-4 months up in northern Delaware sometime soon. Looks like a 'panel' involves 200 watts, but frankly I am not an electrical engineer, and I don't know what's reasonable to do for upcoming travel. Help please.
__________________
2009 Winnebago Vista 26P
gallant205 is offline   Reply With Quote
Old Yesterday, 08:39 AM   #13
Member
 
Join Date: Mar 2022
Posts: 63
Gallant205, You will need major solar and batteries to run a 13.5 roof AC. That is not what you need, and in NE in the woods is even harder to get sun. The OP has some major batteries, but will run them down in a day or less using the A/C depending on sun and if panels are flat or pointed directly at the sun.
A Florida solar user gets more direct light than one in Delaware, so might not need to point panels at all...
You do not calculate how much solar you need based on how high your wattage appliances are, but how much power they use overall. A 900 watt microwave run for 2 mins uses the same power as a 9 watt fan run for 20 hours. So, important to add up "watt hours" which is a mathematical function of power AND time. Many use Amp Hours, but watt hours is easier to calculate for solar.
Bobertgoes is offline   Reply With Quote
Old Today, 08:22 AM   #14
Senior Member
 
Join Date: Dec 2018
Location: California
Posts: 579
Quote:
Originally Posted by Hambones View Post
My panels are wired in series giving me 60 volts with 11 ft of # 6 wire from the roof the the Charge controller. The controller is a Victron MPPT 150/100 (good for 150 volts and 100 amps) From the controller to the disconnect and then to the batteries is 3' of # 6 wire. My 8 batteries are wired together in parallel with 4/0 and 2/0 to my Battery disconnect and then to the inverter. Battleborn say this is all good.

My panels should produce 16.67 amps each (on a perfect day) so I feel as if i should be sending 60-70 amps (realistically) out of my controller if my batteries need it.

Im just not sure what I would see on my Vicron App if my batteries are in a fully or near fully charge state. No one ever told me that. Should I still see what the panels are producing even if I'm not using it? Guess I wasn't near a up on this as I thought.
I think the missing part of the equation is your reading of the available amps. When wiring panels or batteries in series your amps remain "singular" in nature compared to your voltage. Without seeing a wiring diagram of your panel array it's not possible for me to tell what your "on a perfect day" amps would be, but they won't be 60-70 amps. Put it this way for understanding. Two 200 watt, 16.67amp panels wired in series will give you double the rated wattage and voltage, but your amps stay the same....So if you have two sets of panels wired in series, then paralleled your open circuit/no-load amps would be 16.67x2=33.4 amps. I think if you had all five of them daisy-chained together, I think you still have 16.67 open circuit volts. If three of them are daisy-chained then paralleled to the other two in series you're still going to end up with 33.4 amps but again, high watts and voltage.
__________________
V465
2015 Creek Side 20fq, 450 Watts of Samlex Solar,
2013 GMC Denali, Duramax, Retired in 2021
Vintage465 is offline   Reply With Quote
Reply

Tags
install, solar



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar panel install question laveydude26 Monaco Owner's Forum 4 07-18-2020 06:13 PM
To Install or Not To Install (That is the Question) Go Dawgs Trailer Towing and Tow Vehicles Discussion 7 02-06-2019 07:27 AM
Solar Install, but a little different question MeSteve RV Systems & Appliances 6 02-03-2017 11:07 AM
Solar install.. Question about battery compartment and wiring ski2live Going Green 20 10-07-2015 11:39 AM
New Solar System Install kellylipp Going Green 16 07-01-2012 07:44 PM

» Featured Campgrounds

Reviews provided by


All times are GMT -6. The time now is 09:33 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2022, vBulletin Solutions, Inc.