What does a Solar Charge Controller Do in a DIY Camper Electrical System? 

I was charging an RV 12V battery using a new 200w setup. I’m using a 40A MPPT controller. The battery was already at about 80+% SOC. My panels were giving me about 44.3 volts on a clear sunny day. I expected to see at least 5 amps being delivered. I actually saw about 1.31A. Dang! I think I figured that because the battery was already at a fairly high SOC the controller had stepped down the amount of amps being delivered. Right?

Thank you for the information! By the way, Avalanche Amber is one of my favorite beers! 😆

This is a great video series. I think you do a great job of explaining and simplifying this otherwise complex information.

I have a small off grid system with 200 watt solar, 50amp Lifpo4 battery and a 20amp solar charge controller. When sun isn't available, can I disconnect the solar panels from the solar charge controller and attach a 12v 10 amp car battery charger to the solar charge controller input to charge my battery?

Good day Nate Firstly, great RU-vid vlog! Awesome info!!! I need a bit of advice with my system if possible. I ran a PWM controller with a 100w panel on an auxiliary battery that is connected to the starter battery with Cyrix. This only runs a small fridge and worked really well for the past 2 years. Yet I decided to upgrade the system. 2x100w panels in series with a Victron 100/20 controller. Rest of the system stayed the same. I now get a spiking in the system constantly. I have checked and double checked for poor connections and errors but all is 100%. Am I missing something? Many thanks Dewald

I’m wondering which charge controller will work best for my aray I have 15 Astronergy 415 watts I have 10 lithium 12 volt 100 amp lifepo4 batteries 3000 watt victron inverter

Cool yeah...

So I've added equal panels in series to my system, total 300w, and 2 AGM 100ha. I have a WPM controller would it better to change to MTTP.

Well - idea for some improvement: What's about a logic check about input and output voltage: I don't know any charge controller that is able to boost up the solar voltage. Wat is your stand: I would say: so many arrays, I would go for more charge controllers since many - if not most users (campers) having many panels also have different places for them and so different solar direction >> different production. I was told, an array in series can only be efficient as the worst panel is performing (due to sun direction). Are there additional restrictions to panels in parallel if they are exposed in different ways?

I have 4 320 watt Renergy Solar panels 33.7 volts@9.5amps wired 2 sets in series then those two sets in parallel so I have 67.3 volts at 20 amps charging 6 100Ahr BB batteries. My Victron charge controller 100/50 never shows more than approximately 700watts, why?

wow it took an alcohol analogy help me understand solar kudos

The question is How if the landlord leave their home and there is no home's load used while landlords leave their home at all and all batteries is fully charged? Where does the solar panel energy will go or delivered when a daylight time and solar panel within produce the energy condition? Anyone can help to explained to me please?

Very nice, love the app you made, found myself missing an big error when playing with it. Can you have the calculator highlight over/under bad things, like if you are running too small input voltage to the charger for a 48 volt system so it will flag the problem box? Also can you add what charge controller parameters (100/15 example) so if you also over power the controller it will flag you? if you can't that is OK, also you did ask for feedback.

Good clear analogy 🍻

Hii. I want to charge lithium battery byd lvl 15.4 batteries which 12 batteries connected in parallel making a total of 184.8Kwhr battery bank.. i have 545w jinko panels of 60pcs. My question is which victron size mppt smart charge controller should i buy to charge these batteries? Should i buy the 150/100 or 250/100 or the 450/100 or 450/200? I live in dar es salaam tanzania and temperatures here are preety hot throughout the year around 27 degrees - 38 degrees celcius Thanks Nadeem

Its better to charge at higher voltage coz you can use thinner wire coz you use less amps. Higher amp cozes so much heat to some wires depending on the thickness. Its the reason why electric grids transmit power at 1000 to 3000 volts and steps it down with a huge ass transformer

Hey in Explorist! In your 'How to Design a Solar Array for a Camper'. You have this video listed twice. Both in the 1st, and 15th video in the playlist. Just wanted you to know.

I realize you're a MMPT charge controller guy, but what happens if a PWM charge controller is used. Seems like this comparison should have been in a video about how charge controllers work IMO.

So if I had a 750w solar array on my van roof. What battery voltage and charge controller would you recommend? I was thinking 24v

Can any one help me with a very small project? I have a small solar panel connected to a 12volt battery to power a led string of light, but the controler is not auto switching to lit the string of led lights. The battery is charger full with 12 volts, and when I press the controler button does not pass the power to the LED string. I need a controler that charge the battery and them the LED to turn on alone without any interation or switch.

so by the math for every 100w the amps go up by7 on a 12v system. so how and why the amps only goes up all most 7 amps what math is this. but the volts max stays the same for most controllers. There is more here than what we are being told.

i have watch it and still confused. if we do the math v*a=w then if we have a 200w panel why do we / the watts by the charge controller volts?there is a set volts and amps for the panel but we are taking a number that is with another device and making it part of the total of the panel. to me that makes no sense

Whats the name of your calculator?

Thanks for sharing your knowledge . You have saved another life. Thanks.

Good info but way too rapid delivery for a layman with only one cup of coffee this morning! Maybe have to watch again later?

1:10. Dam.

100w/14.5v=6.8amps,200w/14.5v=13.7amps,300w/14.5=20.6amps so for every 100w the panel goes up the amps increase by 7.so here is another example,800w panel take the 8*7=56amps now take 800w/14.5v=55.17amps.this is too precise the volts and amps doesn't matter only the total watts

Great Video ... I see you use any excuse to have a drink while the job gets done.

Hopefully this gets seen, so say if you have 4, 460 watt panels and want to wire them in series parrellel you have 1840 watts are there any good charge controllers for that kind of load or should I split the system into 2 separate power lines of about 920 watts, going to the controller(s)? Am I aiming too high here?

So when shopping for panels should I look for 12v, 24, or 48v panels? I’d like to draw the highest wts possible for my bus from the roof.

Hi, I'm a little confused, I've just used your latest calculator, I input the details but got a recommendation of a 100/30, but according to the figures, a 100/20 will be sufficient ... It's a 420w panel, VOC 37.58, ISC 14.10, 12v Battery, The voltage and amperage are within the tolerance of a 100/20 and probably a 100/15, so yes, confused .....

Great video. Is it normal at night time or anytime the solar leads on controller read the exact same voltage at battery side , like the controller is doesn't exist. Even when sun is shinning shouldn't controller be reading higher volatge somewhere 18+. Not 13.3 , and controller output is also 13.3. Weird.

Hi hoping you could help me with this. 12V System ! Panels =250w Vmp =30.1V Voc =37.3 Imp =8.31A Isc =8.71A Charge Controller is a Renogy 60A MTTP. Nominal Voltage: 12V/24V/36V/48V Auto Recognition (for non-lithium batteries) Rated Charge Current: 60A Rated Load Current: 20A Max. PV Input Power: 800W/12V; 1600W/24V; 2400W/36V; 3200W/48V Max. PV Input Voltage: 150 VDC (25°C), 140VDC (-25°C) Battery's= x2 115AH AGM 12v Wired in Parallel Running a Companion Fridge 24/7 avg power consumption is 0.09amp What is the maximum panels i can use in any given wiring configuration to get the maximum out of my controller and battery's?

so why is there a max volts input watts=watts no matter how it is put together.

I am building my own custom toy hauler and am considering adding solar. My question is when you plug in to shore power with a solar setup does the controller know to not charge the battery? Or how does that work?

Were are you located at? I'm fromm Mississippi. I want solar for my van that I'm starting this year. But I want to run Fridge. microwave .2 📺 tvs Game consoles and wacher dryer combo.and coffee maker..exetera exetera exetera..im willing to have a generator too if I need to. But if I could run it all with solar What I need what setup?..and if I come to you can you install it for me?

Great series! I'd love to see something similar for alternator charging lithium. DC to DC charger or not, high capacity alternators, alternator protection devises and battery isolation managers... What does it all mean! I'd sip whisky with you while you explain it for sure.

Thank you so much for this series of videos! Very well explained and the visuals make it much easier to understand. A solar equipment dealer told me that the panels amps should be around 10% of the battery bank capacity. Do you know what he might have meant by this? I can't find anything about it online. (We have 2x 12v 180ah batteries)

Hey Nate , I am trying to find a 24V battery charger for below battery module - I have the Victron 100/30 Smart Solar MPPT and victron blue smart charger(24V) 24112 - but unfortunately both models doesn't allow me to go down on AB voltage below 25V (with advanced option), where as I need to set the AB and nominal volt around 24.5V .. Do we have any charger / MPPT which supports above volt range (for Tesla Model S Lithium Ion Battery 18650 EV Module - 22.8 Volt, 5.3 kWh) ? any help advise appreciated Capacity: 232Ah, 5.3kWh Voltage nominal: 3.8V/Cell, 22.8V/Module Charge voltage cut-off: 4.2V/Cell, 25.2V/Module Discharging cut-off: 3.3V/Cell, 19.8/Module

Hi Nate, Glad I found you I will cut to the chase because I know you would rather sheer sheep then talk to an old guy who thought he had an original idea- ha I have a 2011 Dodge mini van I did a modular camping set up for my wife and I -test ran last year and loved it, but wanted to do more dry camping (summer time use only) I bought a Jackery1000 I thought it was a one of a kind find in the industry. its new and so cool I have added a home made storage box on top of van, It stores light weight stuff, ie folding chairs-table and out door rug etc. The top of the box is a used 250W 36x65 solar cell (see data below) its on lift struts and I think the combo of Jakery and Solar cell will allow us to camp anywhere :) The problem: I now find out there are several choices out there for portable batteries and the Jacker is limited to 30V on charging. Many questions swimming in head- don’t want to hurt the battery. Nate, If you can spell out the best the best route to make my roof top solar cell work for us -I WILL PAY YOU, and or buy what ever I need from you, Also and buy a sticker and a T-shirt!! Thanks for any help you can give! Here are the stats ... Model ss250P-60 max power W 250 open circuit V 37.6 Current @ Pmax A 8.27 max system Voltage V 600 fuse Rating A 15A

Thankd so much, great video. What do I do if I want to use a Victron Energy 150V 45 A MPPT Charge Controller with a Maximum PV input power at 12V: 650W and my 7 solar panels are run in series with a max voltage of 140 volts and max amps of 10 amps but the total wattage of the panels are 1400 watts which means I've more then doubled the watts of the controller but my volts and amps are under the alloud 150V 45A. Can I still use this charger or do I need a larger watt charger or spit them into 2 chargers? I was hoping I can use this 1 charger since the Volts and Amps are under what they allow.

Is there any harm in oversizing the MPPT? Your calculator tells me I need a 150|85 and Victrons calculator says 150|100. Should I go to the 100 just to be sure? 4x200 2S2P 24v panels. Thanks Nate!

Great video. I want to ask, in the event that you don't have solar panel and you opted for a laptop charger let's say 65w 19.5v and it's connected to the solar charge controller will the charge output rate from the controller decrease?

That answered allot of questions I had but didn't understand. I have about 1800 watts solar, 48 volts in series parallel, charge controller 100 amps but connected to 14.5 volt batteries. It was maxed out at 100 amps. What confused me is I see 2800 watt arrays that only have a 100 amp charge controller. I see now the voltages of the input to the controller and the output to the batteries are different.

I’ve watched this at least 4 times trying to understand that at the end you’re showing 70 A charged at 14.4 V (a 12 v battery) = 1,008 W max. I finally understand the max watt rating. We’ll see how long until I forget that and watch this again lol. Thank you so much for all your videos 💙🔋

Hello and thank you for your great clear and informative explanation on solar power supply. I would like to know if I can use 300w 24v solar allays with 50a solar charge controller to charge 12v 200ah battery. I have single 300w 24v solar panel and 12v 200ah battery

Hi Nate, Been watching your video's and have some questions. I'm getting ready to install solar at my home, DIY. I've contacted several people who have channels/solar info and have gotten no response. I recently purchased 3000 watts in 12v solar panels and I've tried doing the math myself on batteries and other equipment. 100 Ah 12V LiFePO4 Deep Cycle Battery , these are Battle Born Batteries I want to buy 10 of the batteries. I can't even get BBB to contact me about what size charge controller and other things I'm going to need. When I initially contacted the company, they sent me a work sheet and told me if I needed help to contact them. I want to install 110v mini-splits and not use my central unit. I'm at a total fork in the road and don't know what to buy.Any help you can give me would be appreciated. Update to our prior conversations: BBB finally contacted me and I'm even more confused. They did confirm I needed to run 2 parallel strings of panels w/2 charge controllers @48v. So, I said okay I'm good with that. (They did tell me that they were battery manufacturers and not installers.) He asked that I send usage information, which I did based on prior use. My biggest draw is the central unit in my home and is why I'm doing away with it. As I said before I'm going to be installing 4 or 6 mini-splits which draw between 5-7 amps which will not run in unison. 2 days past and this morning I received a message stating I need to buy $28,000.00 in 12v 8d batteries ($2800.00 each). I'm not sure if this was done so I'd quit asking questions or what. So here I am with all these panels and I don't know where to go from here. I've established that I need 2-48v charge controllers but which ones? I really don't mind spending money on the batteries but not $28,000.00. Which batteries exactly? First they said, 48v, then 12v. Still need some help. I don't know what size or what type MPPT.

What do you do when your charge controller is maxed and you want to add a panel? You would have to look for a way around it right? But you don't want to mess things up or take risks.

hi, how to equalize a battery park with 3 regulators connected in parallel

Thank you for this! liked and subscribed!

Thanks for the analogy!! Now you got my attention 😂🤙

Who else expected him to start slurring his words at the end of the video? Great Video Nate!!

Looking at diagram for the OEM 50amp RV upgrade.... I'm not going to use the DC-DC charging but add second MPPT. VIctron has Tr model (supposedly discontinued but still available) and a model that is labeled Tr VE.Can. What is the difference and why would I want one over the other?

Nate, I gotta question. Using a solar array and solar charge controller, can I wire a inverter directly without a battery bank to run during daylight hours only? My dad wants to run a small AC unit during the heat of the day, and I know inverters auto shutdown when the voltage drops below its minimum rating. He doesn't need to run it at night, so a battery bank isn't required...or is it??? Thanks.

U built amazing tool thank you!!! You my teacher #1!!!

Hey Explorist, love the channel but almost didnt click because the RED BORDER makes it look like an "already watched" video. Just giving you a heads up :)

Thanks for relaying you experience to us.

I think it’s helpful.. are you looking for a van that needs wiring for solar? I need help with mine :)

Great videos just wish you would slow down when talking mate .

Brb. Very GOOD. Man. Specifics. SPEAK.

Did you just slam a beer and take a shot as an analogy... wow sneaky

I love how he uses the drinking analogy as an excuse to get drunk

Does this apply only to PWM charge controllers or MPPT also as I thought MPPT adjust everything?

I think I have to go deeper into that liquid comparisons 🤣

Thank You very much ---- clear as a bell !!!!

I did not know that....Thanks Explorist.

I have an unrelated question that you may wish to answer..? I have two (about 8 amps combined) solar generators (herein called sogen(s)) and would like to power both at the same time using one 180 watt solar panel (instead of a separate for each).. Realizing that my sogens cannot be connected together in any way, my solution would be to provide the necessary branch 'Y' mc4 for the panel pos and neg leg, and isolate each pos leg of the branch (to the sogens) with an inline mc4 fuse which already has the diode built in to prevent vdc back charging on the pos legs. Your thoughts..?? If no, then why not..??

0:43. AWESOME bullet points.

Nate, your videos are great but I wish they were numbered!

Lol perfect example!!

0:58. BOOM.

May I suggest that there are perhaps 10 times as many folks with vary limited funds for whom using far less expensive components is simply a requirement. Battleborn makes fine batteries. I wish I could afford them. I can't. Victron 5:43 makes very fine components. I wish I could afford them. I can't. What I can and must do is build a system that achieves 80 percent of the functionality of your high end system at 1/4 of the cost. So you might want to stop the snooty comments. It doesn't become you. In fact think about reaching out to those of us that live on a thousand dollars a month. We won't make you any real money but there are other things in life. ❤

How efficient is the "Victron MultiPlus 2000VA Inverter" compared to the Renogy Inverter/Charger 2000W? In the blog you told the audience the different between cheap & expensive and that's super useful I know Victron uses 1 Ah per hour compared to the 5Ah per hour on Aim, but what about Renogy?

Another fantastic video Nate. Your new calculator is excellent as well. You are nailing it!