One problem with series to consider is that shade on one panel will tend to shut the whole system down, while that wont happen in parallel. So if you expect shadows moving across an array, parallel would produce more power, all else being equal.
Yeah MPPT controllers are even more affordable today than when I made this video. It's the way to go and they give you more options for configuring panels.
Thank you, Sir. Very well explained to make a layman understand the intricacies of PWM, MPPT, Series and Parallel connection of PV Cells. This the way the working of a system should be explained. Precise, concise and exact with no unwanted paraphernalia, that we normally observe. I have watched with stunning amazement, that some members talk and rave and explain things that they themselves are not fully aware of. On the contrary, your study, your experience, you just narrated, went directly into common man’s mind, thought and soul. Bravo! Perfect! My sincere appreciation to you, for the severe hard work you performed, going up the roof, several times, cutting and editing the video and all that. Thanks again.
This may have been answered already (too lazy to read all the responses) but my understanding is that running your panels in series to increase voltage would make sense if the distance from your panels to the batteries is large. Since higher voltage means more efficiency in transmission, you won't lose as much over long runs of wire, and you'll be able to use a smaller gauge. If the panels are located very close to the batteries the parallel would be fine. I'd be interested in seeing a similar test but over a long run of wire between the panels and the controller etc. Regardless, great video simply explained!
After reading many reviews and watching a lot of videos, I chose this option for my first backup power station. ua-cam.com/users/postUgkxHypYDKHAN93Lp2RQpfvU_ksc70wJ00pt I was between this and a larger option that could power a wider range of items, but the price/size/capacity blend seemed right for this unit. Hasn't gotten a ton of use yet, but the build quality is solid and it charges fine via the Rockpals solar panel I purchased to pair with it. One thing to note is that the screen is optimized for a top down viewing angle, which makes sense, but this means it washes out at other angles - especially low angles. Not a huge deal, but perhaps a better option for the display could be used to provide wider viewing angles.
Hello, I hear that if you have 4 x 100 W panels with a MPPT controler the best way to hook them up is to put two in series and then put those two series panels in parallel. This is what I am trying to install on my system. The gain in voltage will reduce your losses with the same wire gauge. This will be more important if you have longer runs. But for short runs, like a RV with a 8 gauge wire I don’t expect much difference. But I will try and measure, this is the only way to know. Thanks for great video.
Thanks, good stuff. One point - series better for low light as parallel panels may be below the level needed to charge, but by adding volts - series - kicks in earlier, drops out later.
Just a small point on parallel vs serial connectivity. The distance or length of cable to the charge controller from the panels can affect the efficiency or effective current to the controller. Voltage drop will occur due to both temperature as well as distance. Ie serial with higher voltage works better over longer distance to a charge controller where parallel is best for shorter distances. Parallel connection give the added advantage of not affecting overall output as much when one panel may be affected by shade. Cable thickness is also a very important consideration depending on which method is chosen.
Thanks for the great videos, it's helped me understand solar so much better than many other channels! One thing I caught that you might not be aware about.... The switch between your panels and charge controller is likely not rated for the 80+ volts you are getting from your system. I have purchased a breaker switch rated for 150vdc for the system I just pieced together, which matches my charge controllers maximum input. The only down side is that it is a rack mount style breaker so it won't look nearly as clean as your switch setup.
Thanks for the heads up. I can't find any ratings on that switch, but I'll keep looking. It's pretty heavy duty though and with the higher voltage, the current is pretty low (at least on the solar side). I'm so glad the videos helped you out. I'll keep em coming. Thanks for watching!
Thanks for the informative video! I'm about to install a 2nd 100 watt panel on my Casita RV, and I was wondering about doing parallel or series. This video clarified the approach I should take. Thanks again!
This is a good video thanks for doing it. One thing to note for people watching for non-RV scenarios, say in a small remote cabin for example, one would want to hook it up in series for the higher voltage IF your panels were some distance from your controller and batteries. For the same reason the electric company has extremely high voltage lines. There's way less loss of energy and way less heat buildup. Cheers.
Nice video! I like how you explain the different options in an unbiased way and give the pros and cons. Lots of ways to skin a cat when it comes to setting up solar power for the RV. Cheers Ray
Love Your RV Thanks Ray! How are those Renogy panels working for you so far? I may pick up a couple of their 50 Watt flexible ones and squeeze them onto the roof.
RVwithTito They worked out well, good bang for the buck. By April with the higher sun and longer days the generator rarely made an appearance. We have pretty meager energy needs mostly computers and charging things up, the big one being my wife's 21" iMac, it can draw 120 watts on its own when she is in a major photo processing session. We are on full hookups for the summer still it's nice because the solar keeps the annoying converter fan from running as the batteries stay charged by the solar most of the day. Next fall when I head back to the desert to boondock for the winter I'll look to add two more 100-watt panels and two more batteries for more capacity for the lower and shorter winter sun.
Thanks alot for being so on point with the difference.Its hard to find just a tec spec video,most people just post stuff like ya a fan works or a drill works,very few gp into specs and over all out come,thanks for video and god bless
I am totally new, I went out and got (don't laugh)harbor freight thunderbolt 100 watt solar panels, I figured a decent newbie kit so I can learn before I dive in. Love the videos makes it easy to follow and learn!
@Tim C - I haven't checked them. First of all, I don't have a PV checker, and second of all, there's nothing I can really do about it since the panels are permanently mounted. I monitor their output through regular use under a consistent load and would notice if the performance starts dropping.
I have tried using mixed matched panels connected in parallel and series with an MPPT charge controller and parallel always gives me more amps, and faster charging times.
Great Job of explaining. I have mixed panels and most videos teach as if it's a new install. this helps a lot. video production is top notch. thanks for the effort.
Nice video. I have these comments. 1) if the panels are wired in series, the wiring is greatly simplified and cleaner. 2) Wiring the panels in series does increase the voltage, but the amperes are less. This should theoretically reduce the losses (voltage drop) in the cables and those losses rob power. I can say that when I install more solar and lithium batteries, I'll be wiring my panels in series and using a MPPT charge controller. This is because the MPPT can tolerate higher voltages produced by the series solar panels and can "harvest" more energy. However, to use a MPPT controller, the solar panel voltage must exceed the battery voltage. In other words, in low light conditions there is no advantage to using a MPPT controller. Keep up the good work!
+Norman Retzke Thats correct, but the disadvantage of connecting panels in series is, if some clouds/obstacals shadows for instance only ONE panel, the whole system voltage drops. So also that has to be concerned (depending on the square foot panels) - This will usually not happen on a parallel mount, here only the Amps drops a bit, depends on the shadowing. this stresses the charge controller usually more less.
Is it possible to install a diode on each panel when wiring in series to isolate a panel that happens to be in shadow or compromised in any other way? Do some panels come prewired with diodes (low cost of diodes it seems they all would)
> in low light conditions there is no advantage to using a MPPT controller An overpaneled system can harvest more in marginal conditions (like low light). Some MPPT can be overpaneled; PWM cannot. > This is because the MPPT can tolerate higher voltages produced by the series solar panels There is nothing special about MPPT and higher voltages _per se_ . You could run 24V panels efficiently w/PWM if your bank is also 24v. Perhaps what you mean is MPPT will get full power when panel and bank voltages are mismatched where PWM will not.
Great presentations! I would like to add (as far as I know) in series if one panel is off that means the whole system are off, in series less and thinner cable required.
Thank you for your thorough explanation and use of examples! I was not aware of the differences between MPPT and PWM, but now I might try to do some more research before getting any more panels. Now I know when to hook them in series and parallel. Thanks again for making this video!
Hello Brian. We are all limited by the square footage on our RV roof. The best place to mount my two 100w panels is towards the front. There is a TV antenna and a vent w/ Max air cover between the panels. I have been observing the shade from these items throughout the day. I am leaning more to a parallel setup verses series. I think the deciding factor is will shading on panels in series reduce the amount of power more than what you gain by hooking them in series. In parallel I estimate one panel will not be shaded for any significant amount of time during charging hours.
Thanks Brian you clarified i had done things right, i added two semi flexible panels to my existing glass panels & wired them in series, i just have to keep an eye on the voltage though as i`m going to be close to the max on my Victron MPPT, greetings from Australia.
If your wires from panel to controller are long you would want a higher voltage - also i think there is a max thru put for the panels before the panel receive damage so it is probably a mix of both series and parallel - put a blanket over the panel when connecting the wires it is a lot of hf energy
I run my off-grid home with four 300 watt panels, in series/parallel. I also use it to charge my Tesla model 3which gets me 4 miles per hour range. That is enough to get me to a Tesla supercharger 135 miles away when I need to travel long distances.
I've been in the planning stages of a solar install for a while now, and this is amazingly helpful info, Brian! Now I know that I want to plan for an MPPT controller that will accept a fairly high level of input voltage, the benefit being that I'll be free from a 'matching panel' constraint, and I'll be able to mix and match solar panels for optimal coverage on the roof.
even if you can't get an mppt controlle. say for example. you have 6 10v panels and 3 20v panels. you can always just make 3 30v series and put those series in parralel. or 3 20v series out of the 10v panels and put them in parralel with the 20v panels. you get the jist of it i guess.
I hooked up an MPPT controller to five 100w panels in series, then a PWM unit to four 24v battery. I then connected the 24v batteries to four 12v ones and taped everything together. The explosion that followed was kinda nice, full of colors.
Hi Brian (RVwithTito), What considerations to you need to take into account about panel shading with the Series vs. Parallel discussion. I've heard that when some of the panels are shaded (Trees etc.) that it makes a difference. What have you seen? Also, which way do you normally have your panels wired? I'm guessing you went with series after the MPPT upgrade.
I have 1120 watts of solar on my RV. My 5kw inverter has a built in mptt solar charger. So I ran all the panels in series and found it was putting out 180 volts! The system book says max is 115 volts. So I changed two 340 watt panels which are identical, I paralleled these two and fed them into the rest of the system circuit in series and the system voltage fell to the-range 80-100 volts, perfect ... for my inverter. I’m running a 48 volt lithium system with 4 x 100 ah batteries giving me a decent a/c power output duration. In addition I run one 12 volt 200 ah battery for the house dc loads. This battery is connected to the alternator via a 30 amp dc/dc Victron charger, and in addition a simple 100 watt solar panel. In addition I have a 30 amp 12 volt (ac powered - mains) lithium charger running of a mains plug. In effect transferring some of the excess solar quickly to the 12 volt house system. Designed and installed by myself and it works. In addition I installed a second 48 volt battery bank, a 2 x 24 volt Ni-cads in series. Aircraft batteries. They have a very similar charge cycle to lithium. This means I can boon dock quite well, run my air conditioning, use my microwave, boil a kettle, a toaster or coffee machine off mains A/C very easily and all at once ! All whilst dry camping ... love to be self sufficient .. it’s a great feeling..
Something elsa people should consider is the length and diameter of the wire runs you have from your panels to your charge controller. If your RV is wired for solar from the factory chances are the wire is fairly light gauge wire. Volts carrie farther in light wire than current will with less loss. So series should work better with long runs and light wire runs. Altho I have read that current or parallel is slightly more efficient power transfer from the panels to the charge controller if the wire runs are of sufficient gauge.
taz man I left the voltage drop issue out of this video. But yes, it is a very important factor. I recommend using a voltage drop calculator to figure out what cable size to use. My goal is to keep the drop less than 1 percent. Here's the one I use: www.rapidtables.com/calc/wire/voltage-drop-calculator.htm. Thanks for the comment.
Ok so I have 2x 40 watt solar panels! Exactly the same! They both came with their own 7 amp charge controllers! I want to hook them up together and hook them up to 2 deep cycle car batteries! Which way should I do this? Very confused? Thanks! 😉
Well done. Thank you for the effort and for sharing. I can see that another benefit of wiring in series is the higher voltage, which will allow for lower power loss with smaller-gauge/higher-resistance wiring. I would think the efficiency would be better at the higher voltages, but I wonder if it's enough to make a difference.
It feels like in this video you're mentioning volts mostly everywhere, but the thing is that amps from the solar also matter. And when you're saying "connect different voltage solar panels" you actually mean "different voltage but same amps", in other case you'll be losing some energy as well.
It only put out 10Amp on both tests because that's what the fridge is using.. the output of the charge controller is already converted to 12/24v for the RV. The fridge will always be 120W/240W. You need a bigger load to test effectively. A load where you're specifically drawing more than the panels allow so the battery starts getting depleted too.
I use ups solar setup and it's technically limited to 48watt charge rate for the deep cell but I can use 2 100 Watt panel in series which the excess power will power the mains dynamically which means the peak wattage output increases .
we occasionally get a shadow across one of our panels. I believe that when wired in series, that shadow takes out both panels. When wired in parallel, that same shadow only takes out o e panel and the second panel will still produce. Have you tested the affects of shadows?
We are going to install two one hundred watt panels (identical) on our boat with an MPPT charge controller that yes can and is rated to handle the higher voltages... We are going to hook them up in series because the run from the Bimini top to the batteries is a bit longer than is "standard" and with the higher voltage and lower amperage on the input we can get away with running lighter gauge wire and not have any voltage drop as a result. No one seems to mention this as the REASON to run series vs parallel but for us this is the engineering reason to do it.
The main reason is volts and wires length and gauge. Always try to have as much volts as possible. So series should be your main goal. Then go parallel when you hit max volts on your controller. Higher volts reduce loss with cables. Go high in volts if you don't want to go crazy on cables gauge and prices.
Why do most people miss the efficiency part? Simply put, it's more efficient to convert 40v DC to 120 AC. If it wasn't we could just use 1.2v DC and convert that to 120 AC. Each conversion, wire, plug and battery is a percentage drop, so the closer you get the more efficient it is.
Brian been missing you. Picked up my new 5th wheel two weeks ago. I was surprised to see it only has one battery so I've been wondering what to do to so I can do some camping off the grid. I did buy a 3kw Honda generator so I can charge the batteries and run one of the AC units if need be. So lots of food for thought. Once I recuperate from my surgery I'm going to be heading to New England for a few weeks. Take care and look forward to be seeing more. Lou
Waters Louis Hey Lou. Great to hear from you. My RV only had one battery initially and I had to make space for another. We're wishing you a good recovery...don't over do it. Keep in touch.
Hi thanx for the video I’m getting in a pickle with my solar . I’m new to m.h. And thought I put a couple of solar panels on roof I bought a set up on eBay and beginning to wish I never lol came with 2x150 mono. With a tracer mppt. Controller they had to be linked in series which I done as per drawing ..not connecting them but just fed them thru roof ,,,,, I connected cables to batteries 2x12v as per instructions... fixed controller to wall .... then offered up pos and neg cables to controller ( batteries were in parallel so I left them at that) ... fixed the cables securely ... all good so far I did notice that the indicator panel was showing the moon indicating night time as the panels weren’t hooked up at that point I thought ok... I then hooked up the leads from panels ( not yet connected ) to the controller .. still moon showing them up to roof and connected the leads for the panels came down to check and still got picture of moon ..?? So wasn’t recognising panels were connected I fiddled with settings on controller but no good ... I have tried to get some sense out of seller but they quote me the instruction manual which I have read thru so not a lot of use ...any ideas colin uk
So well explained! I didnt feel like a kid in a classroom! I have a 120w eco worthy for my van roof but im thinking about adding a jackery 100w solar saga if im stationary and i want a boost to the charging.. They both have the same 18 volt rating but the eco worthy has higher amps/current.. so parrallel seemed to make more sense? as it takes advantage of the eco worthy more... Will also be using eco worthy PWM controller so that will keep the volts down.
Hi Brian, I am going to install my first 100W solar panel on my 2018 Class C Forest River RV. I guess I missed the part where you actually attached a panel. Should I use 1" self-tapping screws to install my 100W solar panel? Btw, I had a RV place install my solar system 2 yrs ago but I got hooked on solar watching you and Will and a bunch of others here on You Tube. So I changed out the Go Power PWM and put in a 30A Epever MTTP controller with its MT50 meter. My 100W panel that I will be installing is a Renogy.
Brilliant ... first clip i begin to understand. I have just bought a solar system for my camper van. 1x 20amp MPPT solar charge controller 1x 150v VOC 22.5v , VPM 18v, ISC 9.00A , Imp 8.33A 1X100v VOC 21.30v, VPM 17.8, ISC 6.07A, Imp 5.62A 2x 110ah V12 Batteries SO i am wondering because the solar are different voltages etc what is the best configuration ??? Many thanks and great work on your channel . DJ
@@RVwithTito Oh sorry I should have been more specific, I mean the ones you used to disconnect the battery and solar leads quickly, they are red. Thank you
Thank you for answering my question!!! BTW, where are you? looks wonderful. I live in Vancouver so would love to know about another beautiful place to dry camp. thank you
@@RVwithTito Thank you Tito... I had thought that maybe it was by the John Day Dam. Take care and thank you for alllll your videos. Yes... Vancouver, WA
Not exactly the greatest info: at 8:22 for instance, you do get 100V, but with the maximum current of the smallest panel! So if you these panels have a max current of 4A, 8A and 3A, you get 100V with only 3A...
I think I'm going to go with parallel. I have a lot of cells and want to keep the voltage under control. The amperage is usually not that big of a problem with solar as I can deal with max 80 amps with a thicker cable.
tHANK YOU!!! We need help with this!! wow. your videos really help! I need to find one for installing the solar panels on the roof so this entire system on our trailer is automatic or close to it.
Parallel miss matched panels just add the wattage. 100w panel and a 80 watt panel will be 180w delivered. If they are in series then you will have a weighted amp value.
You might have placed examples of series in both the cases since in first you put together two panels of 20 volts each receiving 41 volts. In second example you added 4 panes receiving 80 volts. Isn’t it?
Thanks for the video. I want to install 5 x 100 W panels (17.5V each) in Series on my boat with a Victron MPPT 100v/50A charge controller. I like the idea that a) I can use thinner wire b) only have two wires coming through the deck for the 500W array, but I worry about potential partial shading by the rig and lines on the boat. What are your thoughts on the best solution for partial shading?
Great video, question for you, do you think in series that since it puts out a higher voltage, it would start charging sooner/stay charging longer into the day because the panel voltage stays above the minimum to charge for longer? Or does the voltage curve of the solar panel/power of the panels at lower voltages make that a moot point?
Not moot if you have an MPPT charge controller. Higher voltages give the MPPT controller more to work with. So it makes sense that might begin crankin out more power sooner.
Great question, this is what I'm interested in. I just switched my panels from parallel to series this morning and i did see a difference. I was getting 36v 1.5a in parallel right as the sunn was coming up and 68v 3.8a in series but i don't know if i would've got anything a half hour before cause there was no sun and I'm interested in how it'll do late in day. I have 4 300w panels, 6 230ah 6v golf cart pro batteries and a 60a mppt controller which does great all day with little to no clouds (1100w 36.7v 52a) but i usually stop getting good output around 4-430 in parallel (around 150w 36v 2-7a) which sucks cause i don't have anywhere near enough battery storage to maoe it through one night even witout using any power except some chargers (phone, latop, aa battery charger) and a mini fridge so I need to extend the amount of hours I'm bringing in a high amount of power (around 300w 14v 30a+)
He didn't say that if your panels are connected in series and any shade on one panel will affect all panels. But if they are connected in parallel and one panel is shaded all other panels are not affected.
Thanks for explaining this. I am trying to decide whether to connect four 100 watt panels in parallel or series to charge a battery bank of four 6v golf cart batteries connected in series parallel which are about 50' from the panels, or I could use two 190 watt panels in series to reduce the cost of connectors. What would you do? BTW, your wife is gorgeous!
I am still not convinced to go hands down with series on an RV. First, the wire runs are under 20 feet for most RVs, I would think, so more amps from panels with higher voltages should not be necessary. I say this considering that all I need is about 14.5 volts at the battery from the panels and the controller regardless of what they are capable of providing. I believe that if I find that voltage at the battery, the amps have done their job pushing the power along. While I do understand larger gauge is needed with parallel, by the gauge chart, it is still possible to stay with smaller wire with few panels and shorter runs as in the case of most RVs, and, the system is 12 volt. The other concern is that, because the panels are in series, what happens to one impacts all of them. If one panel ends up shaded in a camping spot, it messes up all of them I believe. One advantage I see with series is that while the wattage climbs beyond the needed amount, an MPPT is needed and, that change provides, with series wiring, sooner charges with sunlight rather than waiting for 14.1V to be harnessed before starting. On my small camper, I have one large panel on the roof - 150 watts/22.5V/9.05A rated. I have a 10.5 foot run of 10 gauge copper to the controller. I was told to purchase a PWM even though I planned to add another panel or two in the future as I was told "your system is small with small runs so it does not really matter. With the space you have left you probably could only add 200 watts at most." I have 21.66 volts at the controller from that panel. Now, I have two 100 watt solar suitcases. They each have their own controllers. I went back and forth with solar experts on how to use the three together. Some say one MPPT controller with a mixed series suitcase, direct roof panel connection. Others say having the three with their own controllers does not matter; they will regulate power accordingly. This either or thinking has led me to researching and ultimately to your site as well.
The real reason to connect panels in series is you reach charging voltage (14.5 volts) sooner as the sun is rising (or setting) and you have lesser amps to the controller meaning you can use smaller diameter wire which costs less and less IR drop. IR drop is Amps x Resistance in the wire which is energy loss.
One problem with series to consider is that shade on one panel will tend to shut the whole system down, while that wont happen in parallel. So if you expect shadows moving across an array, parallel would produce more power, all else being equal.
Some people are natural educators. You are great. Thank you.
Thanks Bob for the feedback. I enjoy doing it.
Clearest explanation of the topic I've found. Now I got it.
Great!
I watched 4 lousy videos before seeing how good this one is! Thanks This works.
There was no MPPT that i knew of 20 years ago when I last did this. Many thanks & happy camping.
Yeah MPPT controllers are even more affordable today than when I made this video. It's the way to go and they give you more options for configuring panels.
Nice way to explain to people like me that never have seen solar systems and we're having UA-cam lessons
Extremely helpful!! Thanks for putting out this video!!
Thank you, Sir. Very well explained to make a layman understand the intricacies of PWM, MPPT, Series and Parallel connection of PV Cells. This the way the working of a system should be explained. Precise, concise and exact with no unwanted paraphernalia, that we normally observe. I have watched with stunning amazement, that some members talk and rave and explain things that they themselves are not fully aware of. On the contrary, your study, your experience, you just narrated, went directly into common man’s mind, thought and soul. Bravo! Perfect! My sincere appreciation to you, for the severe hard work you performed, going up the roof, several times, cutting and editing the video and all that. Thanks again.
I like your illustrations & detail depth
This may have been answered already (too lazy to read all the responses) but my understanding is that running your panels in series to increase voltage would make sense if the distance from your panels to the batteries is large. Since higher voltage means more efficiency in transmission, you won't lose as much over long runs of wire, and you'll be able to use a smaller gauge. If the panels are located very close to the batteries the parallel would be fine. I'd be interested in seeing a similar test but over a long run of wire between the panels and the controller etc. Regardless, great video simply explained!
After reading many reviews and watching a lot of videos, I chose this option for my first backup power station. ua-cam.com/users/postUgkxHypYDKHAN93Lp2RQpfvU_ksc70wJ00pt I was between this and a larger option that could power a wider range of items, but the price/size/capacity blend seemed right for this unit. Hasn't gotten a ton of use yet, but the build quality is solid and it charges fine via the Rockpals solar panel I purchased to pair with it. One thing to note is that the screen is optimized for a top down viewing angle, which makes sense, but this means it washes out at other angles - especially low angles. Not a huge deal, but perhaps a better option for the display could be used to provide wider viewing angles.
thank you for a very illustrative example for a little offgrid. Best regards and I wish you a lot of sunshine😊
Hello, I hear that if you have 4 x 100 W panels with a MPPT controler the best way to hook them up is to put two in series and then put those two series panels in parallel.
This is what I am trying to install on my system. The gain in voltage will reduce your losses with the same wire gauge. This will be more important if you have longer runs. But for short runs, like a RV with a 8 gauge wire I don’t expect much difference. But I will try and measure, this is the only way to know. Thanks for great video.
Thank you, I appreciate you taking the time to explain this and I know It wasn't easy climbing up and down to connect and disconnect those panels.
You're very welcome!
Thank you for this
Thanks, good stuff.
One point - series better for low light as parallel panels may be below the level needed to charge, but by adding volts - series - kicks in earlier, drops out later.
Thanks. That's very true.
Great info , easy to understand, thanks Brian, greetings from Australia.
Glad it was helpful. Cheers!
Great rundown Brian. We've had our panels on the roof so long that we sometimes forget about all that went into setting it up. Thanks for the review.
Thank you very much. this was the best video for teaching about use parallel or series.
You're welcome. I'm glad you found it helpful.
Nice job explaining - informative as always. I look forward to your videos.
Just a small point on parallel vs serial connectivity. The distance or length of cable to the charge controller from the panels can affect the efficiency or effective current to the controller. Voltage drop will occur due to both temperature as well as distance. Ie serial with higher voltage works better over longer distance to a charge controller where parallel is best for shorter distances. Parallel connection give the added advantage of not affecting overall output as much when one panel may be affected by shade. Cable thickness is also a very important consideration depending on which method is chosen.
Thanks I have been wondering myself which is best now with your help I can make a better decision on which way to go. Keep up the good work.
Thank u Tito always making class Act 🎬 video reviews.
Love the Columbia river gorge that's where I'm at now I live here just bought a class A and then has prices jump to 5$/gal
Thanks for the great videos, it's helped me understand solar so much better than many other channels! One thing I caught that you might not be aware about.... The switch between your panels and charge controller is likely not rated for the 80+ volts you are getting from your system. I have purchased a breaker switch rated for 150vdc for the system I just pieced together, which matches my charge controllers maximum input. The only down side is that it is a rack mount style breaker so it won't look nearly as clean as your switch setup.
Thanks for the heads up. I can't find any ratings on that switch, but I'll keep looking. It's pretty heavy duty though and with the higher voltage, the current is pretty low (at least on the solar side). I'm so glad the videos helped you out. I'll keep em coming. Thanks for watching!
Thanks for the informative video! I'm about to install a 2nd 100 watt panel on my Casita RV, and I was wondering about doing parallel or series. This video clarified the approach I should take. Thanks again!
This is a good video thanks for doing it. One thing to note for people watching for non-RV scenarios, say in a small remote cabin for example, one would want to hook it up in series for the higher voltage IF your panels were some distance from your controller and batteries. For the same reason the electric company has extremely high voltage lines. There's way less loss of energy and way less heat buildup. Cheers.
You must be stupid.
@@petebradt Your life must be filled with joy. Good luck with all that.
Nice video! I like how you explain the different options in an unbiased way and give the pros and cons. Lots of ways to skin a cat when it comes to setting up solar power for the RV. Cheers Ray
Love Your RV Thanks Ray! How are those Renogy panels working for you so far? I may pick up a couple of their 50 Watt flexible ones and squeeze them onto the roof.
RVwithTito They worked out well, good bang for the buck. By April with the higher sun and longer days the generator rarely made an appearance. We have pretty meager energy needs mostly computers and charging things up, the big one being my wife's 21" iMac, it can draw 120 watts on its own when she is in a major photo processing session.
We are on full hookups for the summer still it's nice because the solar keeps the annoying converter fan from running as the batteries stay charged by the solar most of the day. Next fall when I head back to the desert to boondock for the winter I'll look to add two more 100-watt panels and two more batteries for more capacity for the lower and shorter winter sun.
Great video. Thanks for the helpful info.
Thank you - this video was very helpful.
Well done !!
Thanks alot for being so on point with the difference.Its hard to find just a tec spec video,most people just post stuff like ya a fan works or a drill works,very few gp into specs and over all out come,thanks for video and god bless
I am totally new, I went out and got (don't laugh)harbor freight thunderbolt 100 watt solar panels, I figured a decent newbie kit so I can learn before I dive in. Love the videos makes it easy to follow and learn!
*thanks this helps me to understand what I need to do, I have two of the 180 watts solar panels*
@Tim C - I haven't checked them. First of all, I don't have a PV checker, and second of all, there's nothing I can really do about it since the panels are permanently mounted. I monitor their output through regular use under a consistent load and would notice if the performance starts dropping.
I have tried using mixed matched panels connected in parallel and series with an MPPT charge controller and parallel always gives me more amps, and faster charging times.
Great Job of explaining. I have mixed panels and most videos teach as if it's a new install. this helps a lot. video production is top notch. thanks for the effort.
Nice video. I have these comments. 1) if the panels are wired in series, the wiring is greatly simplified and cleaner. 2) Wiring the panels in series does increase the voltage, but the amperes are less. This should theoretically reduce the losses (voltage drop) in the cables and those losses rob power. I can say that when I install more solar and lithium batteries, I'll be wiring my panels in series and using a MPPT charge controller. This is because the MPPT can tolerate higher voltages produced by the series solar panels and can "harvest" more energy. However, to use a MPPT controller, the solar panel voltage must exceed the battery voltage. In other words, in low light conditions there is no advantage to using a MPPT controller. Keep up the good work!
Great comments Norman. Thanks!
+Norman Retzke
Thats correct, but the disadvantage of connecting panels in series is, if some clouds/obstacals shadows for instance only ONE panel, the whole system voltage drops. So also that has to be concerned (depending on the square foot panels) - This will usually not happen on a parallel mount, here only the Amps drops a bit, depends on the shadowing. this stresses the charge controller usually more less.
Is it possible to install a diode on each panel when wiring in series to isolate a panel that happens to be in shadow or compromised in any other way? Do some panels come prewired with diodes (low cost of diodes it seems they all would)
> in low light conditions there is no advantage to using a MPPT controller
An overpaneled system can harvest more in marginal conditions (like low light). Some MPPT can be overpaneled; PWM cannot.
> This is because the MPPT can tolerate higher voltages produced by the series solar panels
There is nothing special about MPPT and higher voltages _per se_ . You could run 24V panels efficiently w/PWM if your bank is also 24v. Perhaps what you mean is MPPT will get full power when panel and bank voltages are mismatched where PWM will not.
Great video! Very helpful explanation of series vs parallel solar panel wiring!
Great presentations! I would like to add (as far as I know) in series if one panel is off that means the whole system are off, in series less and thinner cable required.
True. Good point!
Thank you for your thorough explanation and use of examples! I was not aware of the differences between MPPT and PWM, but now I might try to do some more research before getting any more panels. Now I know when to hook them in series and parallel. Thanks again for making this video!
This was a relly usefull video Sir...It answered a lot of my questions and thank You for that!
You're welcome. Glad it helped.
Great information bro. Thanks so much for all your hard work and time to bring us this video.
darfirst Thanks. Glad you got something out of it.
Hello Brian. We are all limited by the square footage on our RV roof. The best place to mount my two 100w panels is towards the front. There is a TV antenna and a vent w/ Max air cover between the panels. I have been observing the shade from these items throughout the day. I am leaning more to a parallel setup verses series. I think the deciding factor is will shading on panels in series reduce the amount of power more than what you gain by hooking them in series. In parallel I estimate one panel will not be shaded for any significant amount of time during charging hours.
Thanks Brian you clarified i had done things right, i added two semi flexible panels to my existing glass panels & wired them in series, i just have to keep an eye on the voltage though as i`m going to be close to the max on my Victron MPPT, greetings from Australia.
If your wires from panel to controller are long you would want a higher voltage - also i think there is a max thru put for the panels before the panel receive damage so it is probably a mix of both series and parallel - put a blanket over the panel when connecting the wires it is a lot of hf energy
I run my off-grid home with four 300 watt panels, in series/parallel. I also use it to charge my Tesla model 3which gets me 4 miles per hour range. That is enough to get me to a Tesla supercharger 135 miles away when I need to travel long distances.
Ah, I really thought you were also going to talk about Series-Parallel setups and their benefits.
Excellent video thanks!
3:00
As long as VOC is same, parallel connection should work for dissimilar panels, adding up the amps. So a 100w+80w panel might have 5A+4A or so.
Correct
I've been in the planning stages of a solar install for a while now, and this is amazingly helpful info, Brian!
Now I know that I want to plan for an MPPT controller that will accept a fairly high level of input voltage, the benefit being that I'll be free from a 'matching panel' constraint, and I'll be able to mix and match solar panels for optimal coverage on the roof.
even if you can't get an mppt controlle.
say for example. you have 6 10v panels and 3 20v panels.
you can always just make 3 30v series and put those series in parralel. or 3 20v series out of the 10v panels and put them in parralel with the 20v panels.
you get the jist of it i guess.
@@darkracer1252 PWM is for cheapskates.
Excellent presentation...easy to understand breakdown...thanks...peace...
I hooked up an MPPT controller to five 100w panels in series, then a PWM unit to four 24v battery. I then connected the 24v batteries to four 12v ones and taped everything together.
The explosion that followed was kinda nice, full of colors.
Hi Brian (RVwithTito), What considerations to you need to take into account about panel shading with the Series vs. Parallel discussion. I've heard that when some of the panels are shaded (Trees etc.) that it makes a difference. What have you seen?
Also, which way do you normally have your panels wired? I'm guessing you went with series after the MPPT upgrade.
I have 1120 watts of solar on my RV. My 5kw inverter has a built in mptt solar charger. So I ran all the panels in series and found it was putting out 180 volts! The system book says max is 115 volts. So I changed two 340 watt panels which are identical, I paralleled these two and fed them into the rest of the system circuit in series and the system voltage fell to the-range 80-100 volts, perfect ... for my inverter. I’m running a 48 volt lithium system with 4 x 100 ah batteries giving me a decent a/c power output duration. In addition I run one 12 volt 200 ah battery for the house dc loads. This battery is connected to the alternator via a 30 amp dc/dc Victron charger, and in addition a simple 100 watt solar panel. In addition I have a 30 amp 12 volt (ac powered - mains) lithium charger running of a mains plug. In effect transferring some of the excess solar quickly to the 12 volt house system. Designed and installed by myself and it works. In addition I installed a second 48 volt battery bank, a 2 x 24 volt Ni-cads in series. Aircraft batteries. They have a very similar charge cycle to lithium. This means I can boon dock quite well, run my air conditioning, use my microwave, boil a kettle, a toaster or coffee machine off mains A/C very easily and all at once ! All whilst dry camping ... love to be self sufficient .. it’s a great feeling..
Nice guide, information was great.thanks a lot from India
Something elsa people should consider is the length and diameter of the wire runs you have from your panels to your charge controller. If your RV is wired for solar from the factory chances are the wire is fairly light gauge wire. Volts carrie farther in light wire than current will with less loss. So series should work better with long runs and light wire runs. Altho I have read that current or parallel is slightly more efficient power transfer from the panels to the charge controller if the wire runs are of sufficient gauge.
taz man I left the voltage drop issue out of this video. But yes, it is a very important factor. I recommend using a voltage drop calculator to figure out what cable size to use. My goal is to keep the drop less than 1 percent. Here's the one I use: www.rapidtables.com/calc/wire/voltage-drop-calculator.htm. Thanks for the comment.
Thanks good video
Thank you for all that help you gave me to look in to
Ok so I have 2x 40 watt solar panels! Exactly the same! They both came with their own 7 amp charge controllers! I want to hook them up together and hook them up to 2 deep cycle car batteries! Which way should I do this? Very confused? Thanks! 😉
Connect the outputs of both charge controllers directly to your battery bank pos and neg.
Could you explain? Im a lil slow. I have the same panels/one contoller
Really helpful. Thank you
Great quality with this video! I liked it...
Well done. Thank you for the effort and for sharing. I can see that another benefit of wiring in series is the higher voltage, which will allow for lower power loss with smaller-gauge/higher-resistance wiring. I would think the efficiency would be better at the higher voltages, but I wonder if it's enough to make a difference.
What if positive to positive series?
It feels like in this video you're mentioning volts mostly everywhere, but the thing is that amps from the solar also matter. And when you're saying "connect different voltage solar panels" you actually mean "different voltage but same amps", in other case you'll be losing some energy as well.
It only put out 10Amp on both tests because that's what the fridge is using.. the output of the charge controller is already converted to 12/24v for the RV. The fridge will always be 120W/240W. You need a bigger load to test effectively. A load where you're specifically drawing more than the panels allow so the battery starts getting depleted too.
I use ups solar setup and it's technically limited to 48watt charge rate for the deep cell but I can use 2 100 Watt panel in series which the excess power will power the mains dynamically which means the peak wattage output increases .
we occasionally get a shadow across one of our panels. I believe that when wired in series, that shadow takes out both panels. When wired in parallel, that same shadow only takes out o e panel and the second panel will still produce. Have you tested the affects of shadows?
thanks for the great info.
as long as you have enough power to keep your beers cold that the main thing . as its a question of survival .
That's a good start 👍
When specifically talking about charging and sustaining a battery, which method would be better? higher voltages or higher amperage?
We are going to install two one hundred watt panels (identical) on our boat with an MPPT charge controller that yes can and is rated to handle the higher voltages... We are going to hook them up in series because the run from the Bimini top to the batteries is a bit longer than is "standard" and with the higher voltage and lower amperage on the input we can get away with running lighter gauge wire and not have any voltage drop as a result. No one seems to mention this as the REASON to run series vs parallel but for us this is the engineering reason to do it.
Very impormative, thank you Tito DIY
The main reason is volts and wires length and gauge. Always try to have as much volts as possible. So series should be your main goal. Then go parallel when you hit max volts on your controller. Higher volts reduce loss with cables. Go high in volts if you don't want to go crazy on cables gauge and prices.
I'm envious of your clamp meter... Mine SUCKS, I need one like yours.
Why do most people miss the efficiency part? Simply put, it's more efficient to convert 40v DC to 120 AC. If it wasn't we could just use 1.2v DC and convert that to 120 AC. Each conversion, wire, plug and battery is a percentage drop, so the closer you get the more efficient it is.
Brian been missing you. Picked up my new 5th wheel two weeks ago. I was surprised to see it only has one battery so I've been wondering what to do to so I can do some camping off the grid. I did buy a 3kw Honda generator so I can charge the batteries and run one of the AC units if need be. So lots of food for thought. Once I recuperate from my surgery I'm going to be heading to New England for a few weeks.
Take care and look forward to be seeing more.
Lou
Waters Louis Hey Lou. Great to hear from you. My RV only had one battery initially and I had to make space for another. We're wishing you a good recovery...don't over do it. Keep in touch.
Hi thanx for the video I’m getting in a pickle with my solar . I’m new to m.h. And thought I put a couple of solar panels on roof I bought a set up on eBay and beginning to wish I never lol came with 2x150 mono. With a tracer mppt. Controller they had to be linked in series which I done as per drawing ..not connecting them but just fed them thru roof ,,,,, I connected cables to batteries 2x12v as per instructions... fixed controller to wall .... then offered up pos and neg cables to controller ( batteries were in parallel so I left them at that) ... fixed the cables securely ... all good so far I did notice that the indicator panel was showing the moon indicating night time as the panels weren’t hooked up at that point I thought ok... I then hooked up the leads from panels ( not yet connected ) to the controller .. still moon showing them up to roof and connected the leads for the panels came down to check and still got picture of moon ..?? So wasn’t recognising panels were connected I fiddled with settings on controller but no good ... I have tried to get some sense out of seller but they quote me the instruction manual which I have read thru so not a lot of use ...any ideas colin uk
Great info. Thanks for posting! Hope to see you on the road!
So well explained! I didnt feel like a kid in a classroom! I have a 120w eco worthy for my van roof but im thinking about adding a jackery 100w solar saga if im stationary and i want a boost to the charging.. They both have the same 18 volt rating but the eco worthy has higher amps/current.. so parrallel seemed to make more sense? as it takes advantage of the eco worthy more... Will also be using eco worthy PWM controller so that will keep the volts down.
I ran my panels in parallel, they are identical and in parallel if one panel is shaded it does not effect the output of the other nonshaded panels!
Good idea
I read somewhere that you can use series setup with diodes so shading will not affect the performance.
What?!?! Honestly, being an electrical engineer and watching these people making these videos, I get dumbfounded.
In parallel,the shaded panel will cut the watts. In a series panel connection,ALL will be lost.
I caught that error also.
Hi Brian, I am going to install my first 100W solar panel on my 2018 Class C Forest River RV. I guess I missed the part where you actually attached a panel. Should I use 1" self-tapping screws to install my 100W solar panel? Btw, I had a RV place install my solar system 2 yrs ago but I got hooked on solar watching you and Will and a bunch of others here on You Tube. So I changed out the Go Power PWM and put in a 30A Epever MTTP controller with its MT50 meter. My 100W panel that I will be installing is a Renogy.
Very helpful
Brilliant ... first clip i begin to understand.
I have just bought a solar system for my camper van.
1x 20amp MPPT solar charge controller
1x 150v VOC 22.5v , VPM 18v, ISC 9.00A , Imp 8.33A
1X100v VOC 21.30v, VPM 17.8, ISC 6.07A, Imp 5.62A
2x 110ah V12 Batteries
SO i am wondering because the solar are different voltages etc what is the best configuration ???
Many thanks and great work on your channel . DJ
Thank you very clear explanation
Can I ask where you got those really nice disconnects, thank you for the video, very helpful for the system I am putting together.
Which ones? Those are old-style MC3 connectors. MC4 is the standard now.
@@RVwithTito Oh sorry I should have been more specific, I mean the ones you used to disconnect the battery and solar leads quickly, they are red. Thank you
Thank you for answering my question!!! BTW, where are you? looks wonderful. I live in Vancouver so would love to know about another beautiful place to dry camp. thank you
Vancouver WA? This video was done near the John Day Dam along the Columbia River on the WA side.
@@RVwithTito Thank you Tito... I had thought that maybe it was by the John Day Dam. Take care and thank you for alllll your videos. Yes... Vancouver, WA
Not exactly the greatest info:
at 8:22 for instance, you do get 100V, but with the maximum current of the smallest panel!
So if you these panels have a max current of 4A, 8A and 3A, you get 100V with only 3A...
Exactly.
I think I'm going to go with parallel. I have a lot of cells and want to keep the voltage under control. The amperage is usually not that big of a problem with solar as I can deal with max 80 amps with a thicker cable.
That works. As long as you have the right sized cable.
@@RVwithTito How much can you safely push through 10mm2 solar cable? the connector MC4 is rated at just 30A though...
great video man much appreciated and nicely explained thank you!
Hey. You're welcome!
: ) way over my head. I guess I am stubborn and electricity is just too scary! : ) great video!
tHANK YOU!!! We need help with this!! wow. your videos really help! I need to find one for installing the solar panels on the roof so this entire system on our trailer is automatic or close to it.
Parallel miss matched panels just add the wattage. 100w panel and a 80 watt panel will be 180w delivered.
If they are in series then you will have a weighted amp value.
So helpful. Cheers mate.
You might have placed examples of series in both the cases since in first you put together two panels of 20 volts each receiving 41 volts. In second example you added 4 panes receiving 80 volts. Isn’t it?
As you get same results, it's better series.. because wiring is cheaper :)
I plan on getting identical panels and hooking up in paralell to the same tie in inverter.
No solar charge controller?
Good information, thanks.
Thanks for the video. I want to install 5 x 100 W panels (17.5V each) in Series on my boat with a Victron MPPT 100v/50A charge controller. I like the idea that a) I can use thinner wire b) only have two wires coming through the deck for the 500W array, but I worry about potential partial shading by the rig and lines on the boat. What are your thoughts on the best solution for partial shading?
Great video, question for you, do you think in series that since it puts out a higher voltage, it would start charging sooner/stay charging longer into the day because the panel voltage stays above the minimum to charge for longer? Or does the voltage curve of the solar panel/power of the panels at lower voltages make that a moot point?
Not moot if you have an MPPT charge controller. Higher voltages give the MPPT controller more to work with. So it makes sense that might begin crankin out more power sooner.
Great question, this is what I'm interested in. I just switched my panels from parallel to series this morning and i did see a difference. I was getting 36v 1.5a in parallel right as the sunn was coming up and 68v 3.8a in series but i don't know if i would've got anything a half hour before cause there was no sun and I'm interested in how it'll do late in day. I have 4 300w panels, 6 230ah 6v golf cart pro batteries and a 60a mppt controller which does great all day with little to no clouds (1100w 36.7v 52a) but i usually stop getting good output around 4-430 in parallel (around 150w 36v 2-7a) which sucks cause i don't have anywhere near enough battery storage to maoe it through one night even witout using any power except some chargers (phone, latop, aa battery charger) and a mini fridge so I need to extend the amount of hours I'm bringing in a high amount of power (around 300w 14v 30a+)
He didn't say that if your panels are connected in series and any shade on one panel will affect all panels. But if they are connected in parallel and one panel is shaded all other panels are not affected.
Thanks for explaining this. I am trying to decide whether to connect four 100 watt panels in parallel or series to charge a battery bank of four 6v golf cart batteries connected in series parallel which are about 50' from the panels, or I could use two 190 watt panels in series to reduce the cost of connectors. What would you do? BTW, your wife is gorgeous!
If you've got room for 2 x 190 watt panels, I'd definitely connect them in series given the distance to the controller.
I am still not convinced to go hands down with series on an RV. First, the wire runs are under 20 feet for most RVs, I would think, so more amps from panels with higher voltages should not be necessary. I say this considering that all I need is about 14.5 volts at the battery from the panels and the controller regardless of what they are capable of providing. I believe that if I find that voltage at the battery, the amps have done their job pushing the power along.
While I do understand larger gauge is needed with parallel, by the gauge chart, it is still possible to stay with smaller wire with few panels and shorter runs as in the case of most RVs, and, the system is 12 volt. The other concern is that, because the panels are in series, what happens to one impacts all of them. If one panel ends up shaded in a camping spot, it messes up all of them I believe. One advantage I see with series is that while the wattage climbs beyond the needed amount, an MPPT is needed and, that change provides, with series wiring, sooner charges with sunlight rather than waiting for 14.1V to be harnessed before starting.
On my small camper, I have one large panel on the roof - 150 watts/22.5V/9.05A rated. I have a 10.5 foot run of 10 gauge copper to the controller. I was told to purchase a PWM even though I planned to add another panel or two in the future as I was told "your system is small with small runs so it does not really matter. With the space you have left you probably could only add 200 watts at most." I have 21.66 volts at the controller from that panel. Now, I have two 100 watt solar suitcases. They each have their own controllers. I went back and forth with solar experts on how to use the three together. Some say one MPPT controller with a mixed series suitcase, direct roof panel connection. Others say having the three with their own controllers does not matter; they will regulate power accordingly. This either or thinking has led me to researching and ultimately to your site as well.
The real reason to connect panels in series is you reach charging voltage (14.5 volts) sooner as the sun is rising (or setting) and you have lesser amps to the controller meaning you can use smaller diameter wire which costs less and less IR drop. IR drop is Amps x Resistance in the wire which is energy loss.