How to Fuse a Solar Panel Array for a DIY Camper Electrical System

[@WillProwse]

This is why I do single series string arrays haha I never put panels in parallel these days for this reason. I am too lazy to wire up a ton of breakers. Super good video! I will just direct my viewers to this video. Thanks

[@EXPLORISTlife]

Thanks, Will! Pure series makes things SOOOO much easier from a design, wiring, fusing, and nearly everything else standpoint. I 100% totally agree.

[@JjMn1000]

Ok!

[@jay-rus4437]

LOL....I ended up over here already because you didnt have a video on this Will. I watch all of your vids, and have your book, but you failed us all on this one 😂😂😂😂 Keep up the good work young man.

[@ziggystardog]

Sometimes you have to go parallel or series-parallel if you don’t have high enough voltage or current capability in the charge controller. Shading can be an issue in mobile applications. In these cases it doesn’t pay to be lazy.

[@gabakusa]

but in that case if you have connect them directly to the controller right?

[@FarqueKnowsWhere]

Watched this video again and remembered and learned some more. 😗

[@ruralsolutions825]

OMG!!! Your presentation has just cleared one of the biggest confusion i have been having on PV module installation . Keep up the good work. Thank you friend

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@nomadicconquistador7-5-39]

Hey Nate, As I watch your videos to better my solar education, my girlfriend is listening in the background. She made a comment that should flatter you and your channel. She stated that your voice is soothing to the ear with good clearity and great vocalization of your words. Anyhow that tou should know. Love your channel

[@EXPLORISTlife]

Haha! I've heard that more than once.

[@LonnieWormley]

I just wanted to thank you for your efforts in explaining how to wire up a van. I have been watching your KZbin channel for about two years on how to build a van. I use to have a 5th wheel, but when I retired from being a higher education IT system admin and fix it all networking dude on 1/31/2020 my wife and I decided to get a van instead of another trailer. So in April 2021, we bought a 2017 Ford Transit 350 PowerStroke high-top extended. I downloaded your plans to add to my collection of two other van plans. I wanted to support folks who take the time to share accurate and easy-to-understand information. So anyway, I have a lot of van equipment in my dining room. I am working to get a minimal install in the van for our first trip in September. The van is not going to be completed, but I have a sliding bed and I installed two MaxAir fans. I told my wife that my goal was to get the fans installed, have a bed, and have batteries charging off of our van battery. When I was watching your Airstream build for the third or fourth time I realized that I had calculated my solar incorrectly and I had to order a different solar charge controller. I like the way you explain things in detail without glossing over what is important. Thanks again for all of your hard work.

[@Urge38]

I must say, (and this is NOT a brown nose exercise) I find your PV calculator the easiest to use BY FAR

[@outbackeddie]

Wow - I have been figuring this whole fuse issue wrong. Thanks so much for posting this information.

[@barbm.4301]

These videos are going to save me a lot of anxiety and trusting others who may or may not be competent. Thank you so much for producing all of these instructional videos and blogs.

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@ewetoob6369]

If you are providing good content then you deserve all the ad revenue you receive.

[@Kevin_Aus]

Glad to see another video !! This gives me something else of yours that I can share when people ask me questions about setting up electrics/solar/wiring/etc.. in a van.

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@billhooghuis6819]

Awesome! As an Electrical Engineer, I am quite impressed with your knowledge. Thank you!

[@GeneralKP]

Ask far your videos are the most complete and simple to understand I’ve seen. Thank you!!!!

[@EXPLORISTlife]

No problem. Happy to help!

[@fernandovicente8232]

Thank you for all information! Congrats from Brazil!🇧🇷

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@waynehobbs5175]

You make so much sence. I really don't need another source of information. Thank you from South Australia.

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@TimothyMurray-z5p]

Hi Nate, Do short circuit issues only apply when panels are in parallel? I read all (most) of the comments before asking and it is not explicitly stated, but implied by several messages and your graphs. This is my understanding so far; a) Panels in series - no issues since amps are not added (only voltage is added in series). b) Panels in parallel - fuses may be required since amps are added (in parallel) and total amps may exceed short circuit amperage rating of of the panel (fuse rating). c) Panels in series-parallel - fuses may be required for same reasons as above. It appears only the panels in parallel when the amps are added is where the fuse question becomes an issue. Can you clarify? BTW, you have the knack for educating people on complex topics. Strong work. Tim

[@Downgrader]

I think this answered the question I posed to your other video. 🙂

[@JohnSmith-qd8po]

Great explanation for a very confusing subject.

[@EXPLORISTlife]

Awesome! Glad it helped. Thanks for watching!

[@buildingourdaydream9804]

Excellent description explaining what was, at first, completely over my head. You are an excellent instructor sir! My journey through your series continues!

[@EXPLORISTlife]

Glad it was helpful. Cheers!

[@evil17]

Enjoy ur vids, ur a great teacher, good info & content. Cheers

[@FarqueKnowsWhere]

Thank Nate, understood after a few repeats.

[@witharebelyell2762]

Yes, but HOW do you know what your TOTAL short circuit current is of your entire array? Do you add up each one in series or parallel?

[@esmaponda]

In series current does not add up, it remains the same, however in parallel you add the currunts

[@izdats0]

Let's see if I understood correctly: I have two panels connected in parallel both with short circuit current = 10.269A, would short circuit current be added, too, for a total of 20.538A? Max series fuse on the panel is 20A, so would I need a 20A fuse on both panel's positive cable before they go to the parallel connector? Loving the videos btw, I'm learning a lot and found I did a couple things right on my starter system!

[@ttirrell]

Thanks Nate! I have 2 panels wired in series with no fuse. I THOUGHT that would be ok, but now I have the data to back it up.

[@EXPLORISTlife]

No problem! Good deal! Pure-series wired arrays RARELY (Never?) need fuses.

[@dwighthapeman6590]

Your videos are so complete and so easy to follow! Thank you so much for all the time you spend making them.

[@treemaniscool]

Amazing videos, I've been looking at battleborn batteries and some local suppliers of panels to try and offgrid some appliances but there was so much information and much of it conflicting. This entire series puts it all together in easy clear ways with fantastic visuals!

[@gohoop]

This was very helpful. Thanks!

[@sailor7025]

Great to see you're back Nate! Your videos regarding solar anything are absolutely the best. Additionally, the interactive diagrams and associated ordering list are waaaaaay cool! Hope you and Steph are doing well.

[@EXPLORISTlife]

Hey Sailor70, Thanks so much! Doing good here. Just wrapping up some big projects that have pulled me away from KZbin for a bit, but doing good. Cheers!

[@MarkMettler]

Something I agree on. Thank you for enlightening the DIY group. I have yet to get serious about the 4S4P solution with my panels and inverter. I have a Growatt 80A with a 60-145V range. The panels are 260W 30.6V 8.5A and knowing the fuse solution leaves me cautious with a 3S2P. I could do 4s4P-5P even. 122.4V at 34A - 42.5A but then where goes the fuses? Brave men burn down their homes. I shall wait until I've absorbed more knowledge. Of course, there is always the wire to consider.

[@winginitwithjohn8451]

Great timing. This video I hoped would clarify, but, maybe it went by me too fast? I'll read the blog post too. Thanks. I was in the process of fusing my Lynx distributer, I'll send those Q's to the EL private crew.

[@EXPLORISTlife]

Thanks! Yeah, downstream of the charge controller will be covered in an upcoming video

[@KENZIIE_lol]

Do the fuses in a combiner box pretty much do the same thing?

[@markhouse9570]

THANK YOU for these extremely instructive videos! They've given me enough knowledge to get most of the way into design on a motorhome roof 1200W 12V array. Panel: Newpowa 210S-12H. Vmp 16.77 V, Imp 12.48 A, Max Ser Fu rating 15A. Two 3-panel banks, S/P I see (2) series circuits producing 50.31V @ 12.48A. Paralleling them I calculate final out of 50.31V @ 24.96A (not adding for temp). Do I understand correctly that I need to fuse before or after the Y branch parallel cable(rated 30A) up on the roof, and if so, what fuse size in each leg? (figuring the Isc for the entire array is 39.27 x 1.25=49.1A and the Max Ser Fu rating is 15A) I'll be dropping to a breaker/disconnect before the Victron MPPT 150/85TR.

[@arecibo1974]

This information is awesome, thank you!

[@EXPLORISTlife]

Glad it was helpful. Cheers!

[@sergioriveros5873]

Hey Nate... nice video... thank you for sharing. Speaking on sharing... would you share with us the excel spreadsheet ?

[@WoodandWild]

Hi Nate, thanks for the very informative videos. Could I use the x 1.25 rule to size the fuses for the panels? I gather you use the maximum fuse rating as the panels components can handle that amount of current and is probably simpler to do, but I've already bought a bunch of 10a fuses for solar panels with a 5.51a short-circuit current, would they still be ok to use? Just out of interest, why do you place the fuses before the branch connectors and not afterwards? Just I noticed alot of places like Renogy specify placing fuses after the branch connectors. Does it mean that in the case of a short circuit and the fuse is blown, that just the one panel would stop working rather than all 3 tied into that branch? Many thanks in advance! Joe

[@etibo6]

Hi, you make one of the best learning videos. Question for you, on the back of my panel, the max series fuse rating is not written, Do you know how to get it if it's not possible to talk with the fabricant?

[@iamnegan1515]

Excellent explanation.

[@EXPLORISTlife]

Glad it was helpful. Cheers!

[@carrottop3454]

So I have 8-200 watt rich panels that I plan on wiring in 2 series strings then connecting those in parallel so I can max out my watts input for eco flow power station. The short circuit current for each panel is 10.2. So that would stay the same for each string but when I wire them in parallel it would then be 20.4. Would I need to fuse these at the Y branch connectors?

[@memilanuk]

Great videos, they are very helpful. I especially like the way you break things down into appropriate bite-sized chunks 👍 That said... I think you may have wrong video linked in the show notes for determining short circuit current. The URL provided goes to the series-parallel video a couple of episodes back, not the one linked elsewhere from fall 2019. A minor quibble, otherwise you're doing great!

[@MyGoogleYoutube]

So, my solar setup doesn't require fusing based on your video. Does it also not need a DC breaker? Could I just use a DC isolator? Love your content - thank you.

[@cardinhamkilligrew9712]

I am looking at a 600 watt solar array. (sailboat with some shading possible) 100 watt panels. 2 x 100 watt panels in series. the the 3 sets in arrays. The panels have this rating: Open circuit voltage 21.6 V Maximum power point voltage 18 V Short-circuit current 6.11 A Maximum power point current 5.55 A Would I need a fuse in this scenario? the set up i believe would be: SERIES PARRALELL 3 solar banks (each 2x100 watt panels) 3 - 200 watt solar banks in series then parallel 600 watts (40 volts at 15 amps) 100/50 charge controller 10 Gauge Wire Am I correct on all this? These videos are AMAZING!!!!! Best Ive seen

[@loganreynolds4396]

Awesome information. Appreciate all the work you do. Quick question, I have 4 550w panels I plan on adding to the top of my bus. I need help determining between parallel or parallel series, and then sizing my fuses. IMP: 13.11 VMP: 41.96 ISC:14.01 VOC: 49.9 I cannot find max series fuse rating ANYWHERE, only maximum system voltage which is 1000 I calculated the short circuit (14.01) x 1.56= 21.86.. so if doing parallel I would need 30a inline fuse prior to the 4 to 1 mc4 connectors. What I then am getting confused about is after the 4 to 1, that would be (21.86 x4) 87.44 amps running thru that connector and would not be able to handle it, right? Or would a 100am pv isolator be after the 4 to 1? Any and all help would be appreciated.

[@Kylosgrande]

The example you first showed if it was wired in series parallel what it need a fuse? - I am doing exactly that, 4 12v 100w panels in series parallel,

[@christopherschulteshinesth1415]

Keep up the good work!

[@EXPLORISTlife]

Hey Christopher Michael, Thanks so much! Cheers!

[@thomasansieta2639]

Good videos I have learn a lot question I am starting a system for my cabin have 4 panels 300watts each panel is better parallel or serial

[@EXPLORISTlife]

Hey, thomas ansieta! I appreciate you taking the time to ask your question, but unfortunately, I don't have enough info about your specific question to provide an accurate answer, but here is a playlist that, if you watch all of the videos start-to-finish (and take notes 😉), you'll have a REALLY good idea of how to design a solar array: kzbin.info/www/bejne/gJzFpGtqqKd7qck Alternatively, I have some of my most common solar array setups pre-built here: shop.explorist.life/product-category/all-products/camper-wiring-kits/solar-charging-wiring-kits/

[@zonaverde-ranchosai3106]

Can I use vehicle fuses? Am really really off grid for specific components

[@sovereignsoultribe]

Question : I am installing 6 x 150w solar panels to my bus in parallel. each panel has a 15A rating. Am i right in saying I DO need individual fuses installed for each positive connector? Thank you in advanced :)

[@gaborjakab3030]

Hi! Thanks for the video. I am far away not an electrician. What would be the functionnof the bypass diodes on the panels? Is there any additional protection from the inverter side? Thanks

[@jonathanxing2843]

Great Video, Can I please ask what software do you use to make the diagrams? I would like to design my own system and looking for the software to do sketches.

[@davebenz8271]

They are great. I’d like to know, too.

[@5chips]

Hello Nate, I am a new subscriber and find your videos very informative. I have a question about fusing. Do two 160 watt solar panels connected in parallel have to be fused. Both have a short circuit current of 8.37 amps, optimum operating current of 7.92 amps and a max. series fuse rating of 15 amps? I think the answer is no, but not sure. Much appreciated, thank you.

[@EXPLORISTlife]

Does your array short circuit current exceed your max series fuse rating? Here's how to figure out your array amperage: kzbin.info/www/bejne/gXuYq3aPaqp1m7M

[@joe84bmw]

I have one panel that’s 15a and came with the rv and adding two more that are 20a rated. All are renogy 200 watt panels, would I use a 15a and 2 20a fuses or make them all 15a? Im not very good at this 🥴

[@chriscourtney5692]

*quick rundown* I have 4- 100w panels, p30L charge controller, 2- 200AH deep cell agm batteries, and a 1000w pure sine wave inverter charger, with 4 outlets run in parallel, that will be hardwired into the inverter charger. Do I need a breaker box anywhere? Or will properly placed fuses between components provide adequate protection.

[@CharlesLangSamuel]

Very well explained thank you.

[@jeffdidit8740]

Question: when figuring out if you need fuses and also wire size, do you use the stc wattage, or the maximum wattage for calculation? I have renogy 115w bifacial panels that have a max power stc of 115w, but it has a capability of 149w under optimal conditions. So in my calculations do i calculate using the 115 or 149? Thank you and I'm glad i found your channel as I've been struggling getting a straightforward answer on many applications even from renogy customer service itself.

[@EXPLORISTlife]

Whatever the max stated wattage is.

[@madcow3417]

You just saved me from doing it wrong. Thanks!

[@esliemarcelo2963]

most helpful tips.thnx..

[@whitesamarrow733]

Hello, nice video. ISC of my solar array is 22.44A Maximum series fuse is 20A Must I put 20A fuse on each Double 2 in 1 MC4 combiner? Thanks in advance

[@nikolasdassis]

Hi I want to make a setup with 6 solar panels total. They will goi either in 2s3p or in 3s2p. The maximum series fuse rating for the 1 panel is 15A, my question is, if I go to the 2s3p configuration or the 3s2p what kind of fuses should I install? Thanks for any help.

[@tonym2540]

You're presentation of what the current does when a short appears in 3 panels connected in parallel was very helpful. Thank you, thank you, thank you! But once I understood it, I tried to apply that reasoning to the 3 panels in series and got confused. I came to the conclusion fusing in any pure series arrangement would never be needed since the currents never add. Is that right? (Still learning...)

[@EXPLORISTlife]

Fusing in a purely series array is indeed never needed. Nice work!

[@BurnProcessMedia]

I am using the same Rich Solar 200w 12v panels as shown above. They will be wired in 3S2P. Each sting will produce the 9.8a but the strings when parallel will be 19.6a exceeding the individual panels 15a max fuse rating at the combiner. Where (if at all) would I fuse this array and what fuse capacity would I use? This is an amazing video btw. Thanks for all you do. You and Will Prowse have become my Gurus.

[@andresjoubert]

I have the exact same array setup I am preparing to install. 6 Rich Solar 200W 12v panels in 3s2p configuration. Was this question ever answered, and if so, what was the verdict? Fuse required or not? If so, what rating fuse?

[@BurnProcessMedia]

@@andresjoubert nope, it wasn’t answered unfortunately.

[@EXPLORISTlife]

I didn't give this one a personal answer as the video answers the question. 🙂👍 If the array amperage exceeds the max series fuse rating, it needs fuses.

[@melaniecollins4045]

Hi Nate, we are wiring 840 watts of solar in series/ parallel and am wondering if our short circuit amp is 10.86 per series would we only need a 15 amp fuse or 20 amp fuse? our specs our for a 20 amp fuse. Thanks

[@lavaredwards3170]

are these concepts usable with home installation

[@FarqueKnowsWhere]

Hi Nate, i have 2x190w Enerdrive solar panels (type SP-EN190w) I want to connect in series. It has no max series fuse rating on the label or website. I emailed Enerdrive for this information and they replied they don’t recommend series connection for 12v systems, and max series fuse rating is for grid connection and they don’t do this. Is there a reason they don’t recommend series connection for a 12v system? And I was given the formula W/V=Amps to work out the fusing I assume. Can I connect these panels in series and how or can the MSF rating be determined? Thanks

[@minceym]

Hey Nate I'm still a beginner and some of this went right over my head 😳 Any who can you tell me if I need to fuse these two panels for my solar generator in parallel? JA SOLAR JAM54S31-395/MR RATED MAXIMUM POWER (Pmax) [W] 395 OPEN CIRCUIT VOLTAGE (VOC) [V] 36.98 MAXIMUM POWER VOLTAGE (Vmp) [V] 30.84 SHORT CIRCUIT CURRENT (lsc) [A] 13.70 MAXIMUM POWER CURRENT (lmp) [A] 12.81 MODULE EFFCIENCY 20.2 The specs reads as: Maximum Series Fuse Rating 25A not sure if this is what you were referring to. Thx!

[@Supanova70]

Ok so if i got this right i have 2/100w panels @5.5 a short circuit ratings each. A 10 amp fuse each panel is what i need wired in paralell?

[@jaffasoft8976]

What size fuse is needed? Is the fuse for each panel the same size fuse as the max fuse desciption on the panel and then how do you size a fuse into an array ? I got Short Circuit Current 11.39amp and Maximum Series Fuse as 20 amp, 2s2p . Will i use 20amp fuse in each panel and 40amp fuse in each series fuse then into the charge controller??

[@leoclarkin5944]

If Voc panel voltage is an issue, i.e., it exceeds solar charge controllers max input voltage, does it make some sense just to install an additional MPPT vice putting up to parallel wiring issues?

[@davidniquot6423]

Nice info, thanks.

Hi Nate. Great video. My 3s3p short circuit rating is 16.8 (5.6x3) amps My Fuse rating on panels says 15amps. Will I need to fuse it is that not much over to not worry? Regards Phillip

[@EXPLORISTlife]

Like mentioned in the video: is your short circuit rating more than the fuse rating? If so... it needs to be fused.

@@EXPLORISTlifethanks Nate. Appreciate your advice

[@robertpeyton5534]

First of all, thank you for your videos. I have eight 400 watt Solar panels, the Voc is 49.3 volts. my charge controller is a tracer 4215 BN maximum voltage 150 input. I am running an off grid 12 V inverter to make my 120 v. My question is, will I need 4 charge controllers like this one to handle the solar panels and stay with 10 gauge wire. I think that’s what I have to do..I’m just double checking. Thanks, Rob

[@EXPLORISTlife]

There is indeed a pretty strong chance you'd need 4x charge controllers.

[@marklandry8706]

Nate....all great info...quick question on future solar expansion...any reason to not oversize solar controller with expansion of panels and batteries down the road...?

[@EXPLORISTlife]

That's a good idea. Set up an 'end goal' and work backwards from there.

[@kirbyspencer538]

Just keep an eye out for the possibility of over-currenting your battery during bulk charging.

[@walterschilling4512]

Hello Nate , Being consistant with your example of the panels in parallel , with those same specs can I use a 16a breaker on each panel .

[@EXPLORISTlife]

I'm not sure I follow... Are you asking if you can use a fuse size larger than the max series fuse size listed on the panel?

[@shimpiden]

what about matching panel VOC to the controllers stated maximum VOC input ?

[@leonelhernandez3618]

Hello, thanks for share this video. BTW how did you build that pretty diagrams, can suggest any software for do that?

[@EXPLORISTlife]

Glad it helped! I use Microsoft Visio to make all of my diagrams.

[@bertweeb1989]

I don't have an RV but solar power is quite interesting.

[@EXPLORISTlife]

Hey Bert weeb, No problem! Glad it helped! :)

[@aysensvoboda2274]

Great video. May I ask which tool you use for those drawings? Thank you

[@EXPLORISTlife]

Microsoft Visio

[@aysensvoboda2274]

@@EXPLORISTlife Thank you for such a quick answer!!

[@frankt7769]

Hi I have 2 parallel solar panels running to my victron 100 20a than to my battery box the battery box has a 16a circuit breaker do I still need to put a fuse on my battery box

[@danielreger5463]

Great videos. Best help I have found. I cannot figure out the fuse between battery and controller. Manual of Renogy Rover 40 amp Mppt states to match the rating of the controller, so 40 amps. I am running two 160W renogy flex panels in parrallel. 8.88a short ciruit current. 20 amp Max Series fuse rating. Is it even possible to achieve 40 amps of current with that setup? Thanks for what you do!

[@EXPLORISTlife]

A 40A charge controller is indeed capable of putting out 40A. As for why Renogy recommends that; I cannot say. I know that Victron and most other quality charge controller brands recommend the fuse be somewhere in the ballpark of 125% of the capacity of the charge controller given proper wire sizing so the fuse won't blow under normal operating conditions.

[@thomasansieta2639]

my solar controller is a renogy 100 Amps and pure inverter 2000w renogy have eight batteries 192 amps gel planning on installing them on 24 volts series batteries based on your knowledge is this ok or you suggest something different, thank for your input lived up north in Canada not much sun in the winter in ONTARIO

[@EXPLORISTlife]

Hey, thomas ansieta! I appreciate you taking the time to ask your question, but unfortunately, I don't have enough info about your specific question to provide an accurate answer, but here is a playlist that, if you watch all of the videos start-to-finish (and take notes 😉), you'll have a REALLY good idea of how to design a solar array: kzbin.info/www/bejne/gJzFpGtqqKd7qck Alternatively, I have some of my most common solar array setups pre-built here: shop.explorist.life/product-category/all-products/camper-wiring-kits/solar-charging-wiring-kits/

[@wilfredomarino3413]

Idol how about in batery connection.parallel connection also need to fuse?if how.thanks

[@tullgutten]

I have 1 string and a fuse on both poles right before the DC over voltage shunt so if Lightning strikes and the over voltage gets tripped i hope the fuses blow BEFORE any fire starts or the inverter blows up. Grid tie Solar Edge inverter and panels. Don't "need" it but want it 😁

[@billm6852]

When is the "next video" coming out? I am looking for info on the breaker between the solar panels and the charge controller. I checked your web page but did not see an article there yet either. Looking forward to it !

[@EXPLORISTlife]

This Sunday if UPS gets here tomorrow with a few parts I'm waiting on! 😆

[@mallorymcguire833]

What's a little unclear is you're saying the short circuit current of the "entire array." Does that mean if we have two panels that have 10.2a on the sticker, the "entire array" would be 20.4 amps? Because if we wire in series the amps stay the same, right? So my short circuit current on the sticker shows 10.2 and the max fuse rating is 15. Does that mean I don't need to fuse, or does the "entire array" mean 20.4 amps? Or does the entire array term apply only to panels wired in parallel?

[@Nuke553]

This might seem like a silly question.. I am getting ready to install my panels. I plan on adding tilt bars, does it matter when laying them out if they tilt lengthwise vs width? If I lay them out to tilt up lengthwise (taller vs wide) I can fit more panels in the future. I can still fit all 4 width wise but it leaves little room for expansion later on down the road.

[@EXPLORISTlife]

It shouldn't matter. :)

[@kingaspis]

Hi Nate, I"m having a hard time finding the max series fuse rating for my panel as it's not on the back sticker and can't find it on the manufacturer's website. Can you help? Newpowa model NPA180S-12H (180W mono). Thanks!

[@johnboling]

What do you use to make your wiring diagrams? Always so clean.

[@EXPLORISTlife]

Thanks! I use Microsoft Visio for all of my diagrams.

[@leemobai762]

Great video. Love the schematics. May I ask what do you use to draw them.

[@EXPLORISTlife]

I use Microsoft Video for my diagrams.

[@leemobai762]

@@EXPLORISTlife Thanks - you got to hate spellcheckers. I know you meant Visio.

[@WiSeNhEiMeR-1369]

HOWdy E-l-DIY-C, ... Thanks COOP the WiSeNhEiMeR from Richmond, INDIANA ...

[@adventure_onthedaily9851]

Hi there, might be a silly question but my solar panels don't have the maximum series fuse rating on the sticker. I'm in Australia and purchased them here, if that matters at all. i'm using 2 x 200w panels wired in parallel, with a short circuit current for the array at 22A. If it's not listed on my panels, how do I know if I need inline fuses? thanks so much for any advice!

[@EXPLORISTlife]

If the Max Series Fuse Size isn't listed, you can take the short circuit current x 1.25 and then round up to the nearest interval of 5.

[@mikenkaried4543]

GREAT VIDEO! It seems very hard to really get that design conversation laid out for discussion... One Advanced Question I have on that "in-series" fuse layout Idea. Let's say you have two in-series banks, each bank is 3 panels and each panel has an open c. volt rating of 49.8v and a short c. amp rating of 10.36amp, and directly at each panel connection in the series you use an MC4 connector that contains a cheap replaceable 15amp fuse so that it is closest to the source and slightly greater than nominal just in case one panel has a short circuit problem preventing damage to the rest in that series, if one single fuse (6 total) blows I believe that shuts off that entire 3 panel series, but my question is.. since that series is parallel to another 3 panel set will it cause any issues using the remaining 3 panel series for charging at only 10 amps and 150v, vs 20amps at 150volts? I know some MPPT chargers want sufficient amps to even begin charging efficiently. I have periodically detected some volt fluctuations back fed up the wire when only charging 12 volt batteries using this array when only one series is switched on, so either its a MPPT charger issue or this tiny fuse "in line" in a series is a bad idea for some electrical current reason.

[@EXPLORISTlife]

I'm not sure I entirely follow, but if a fuse blows...I recommend replacing it as soon as possible after the problem that caused it to blow is fixed. I don't like playing the 'what if' game with halfway broken systems. I'd rather just fix it so it works as designed.

[@mikenkaried4543]

@@EXPLORISTlife was trying to decide proper fuse placement by looking at what happens if a fuse pops. Does it cause other things to break by imbalancing sets or just kill the series and if so what are the ramifications moments later if it takes hours or days to get a replacement fuse.

[@EXPLORISTlife]

@@mikenkaried4543 I see. If a fuse blows, it just disables that series string and isolates the fault to that series string which would then continue to operate (not connected to the charge controller) at it's short circuit current, which the panels are rated for without the other series strings adding to the problem. The other series strings would continue to provide power to the charge controller.

[@giuliobaecker5476]

What do you think about the Eco Worthy boxes?

[@EXPLORISTlife]

I don't have any first hand experience with them. I recommend Victron components for a high quality system that will last.

[@giuliobaecker5476]

@@EXPLORISTlife thanks, I’m going with a Victron 150/60 charge controller. Will be running 4, 340w (48v) panels to charge a 12v battery bank. Sound ok? My understanding is I can have high voltage into that controller under 150v and 60amp, and it will down the V to charge the 12v battery bank

[@EXPLORISTlife]

Not quite. The 2nd number of a charge controller is the amperage OUTPUT; not input. More info: kzbin.info/www/bejne/gJzFpGtqqKd7qck and this: kzbin.info/www/bejne/g6ndmnuBq7mFnpo 1360W of solar charging a 12V Battery Bank at 14.5V is 93A (1360W / 14.5V = 93A), so you'd actually need the larger MPPT 150/100: shop.explorist.life/shop/all-products/solar-charge-controllers/victron-smartsolar-mppt-150100/ You could use this kit, just substituting in your 340w panels, and omitting one panel per series string: shop.explorist.life/shop/all-products/camper-wiring-kits/solar-charging-wiring-kits/1440w-solar-charging-wiring-kit-6x-240w-12v-battery-bank/

[@giuliobaecker5476]

@@EXPLORISTlife thanks so much! Really! Thanks I put in a small system 5 years ago and it’s time to actually upgrade to something more substantial

[@giuliobaecker5476]

@@EXPLORISTlife Do you ship to Canada?

[@CountryBoyMoto]

my solar panels do not required a fuse but would that give me protection against a lightning strike or would the strike destroy everything anyway due to the power of it

[@EXPLORISTlife]

The only thing that can really protect against lightning strikes is having good insurance with all of your camper electrical equipment on the policy. 😂👍

[@kevinmatthews2620]

question for you, i am finalising wiring this weekend for a friend of mine he has 2 identical longi panels installed on his shed roof both 445w rated max power,the have a max short circuit current each of of 11.53 a,, current @ pmax of of 10.78 amps, max system voltage of 1500v, max series fuse rating of 20 amps, we wish to wire both together to get the most watts/amps out of them (the voltage pmax is 41.3v ), they will be feeding to a string of 8 12v batteries and in turn the 12v power will be feeding to a victron quattro 12v 5kva system, what fuse do i need i am confused by the series/parellel and the info on the labels ?? pps , these are new current generation Longi panels about 3 months old, they are currently both seperate running 2 charge controllers,here in the uk dc isolaters are super expensive, i was going to use standard mcbs of the correct amperage on both lines to act as a dc isolation, is this right/wrong ??, i have the victron putting out 240v ac with no problem off of 2 rolls batteries that are currently contacted, the remaining 6 lead acid 220ah batteries will be wired for 12v this weekend on the second dc in line on the victron, the victron has a main off box(external to the unit) with 2 lines each already fused with mega fuses of 500 amp times 2, which according to the victron specs exceeds the 800 a min fuse rating, please help :) :)

[@faridmohsini9225]

I have total of 12 panels 100watt renogy solar panels I am about to install 6 panels in series and planning to connect to set of 6 panels in parallel Do I need a fuse. If you answer this will help my project thanks

[@EXPLORISTlife]

This video will teach you how to determine if you need a fuse in your solar array: kzbin.info/www/bejne/qWKzZGSerdF3aas

[@nwlady1844]

Plz help! I just received my two new acopower 120w foldable solar panals. there is no "max series fuse rating"... on the back of the panel.... on the website and... I have emailed the acopower requesting this information.... no response. Should I be sending back these panels? Are they missing something like a fuse that they should have? Thank you for any help

[@mattr7229]

Thanks so much Nate for all the immensely helpful videos you have made... Question for you... in Case study #1 at 3:18, you show panels A, B, C where C is the right most panel and it has a failure causing it to short out. From Kirchoff's current law, you get the 20.4 amps (total from panels A and B) going through panel C. The part I am unclear on is you show the total potential current thought panel C at 30.6 amps. In a real world scenario, if though panel C has a failure (e.g. short), it is *possible* for it to still be operational to produce current? I have no knowledge of the mechanism of solar panels and hopefully I will learn something but it would seem if the panel fails, it wouldn't be capable of producing current. However, even if the 20.4 amps were the only current, based upon your example, the fusing would still be required. Thanks!

[@stevengiraldogarcia8117]

I have the same question!

[@powderdayallday]

It depends how the solar panels fails... they are basically made up of multiple smaller cells connected together. The "Maximum Series Fuse Rating" on the panel is the upper limit of what the internal connections between the solar cells INSIDE the panel can handle before failure. If one of these internal connections fails, the individual cells inside the panel are still capable of producing power (individually, just not exporting it from the solar panel). There is a chance that the fault could result in an internal short (and maybe an external return path? frame?), and when connected in parallel, the external fault current will contribute to the internal fault.

[@qquizz]

I take it if you just have a single panel, no fuse is needed, and that it doesn't even offer redundant protection...correct?

[@maninavan.2043]

Please, help I have three 100wt solar panels and keep being told to fuse them independently. And some say I don't. I have the three going into one and a breaker leading from that (+) cable. And a circuit breaker on it leading to my charge controller.

[@chrisbroom8418]

Hi. I have 4 X 100w renology solar panels wired in series parrallel.I have a renology 60A mttp. do i need to use fuses and if so what size do you suggest.

[@EXPLORISTlife]

Hey, Chris Broom! I appreciate you taking the time to ask your question, but the video you just watched will teach you how to determine if your solar array needs fuses and what size. I've provided the information; now you need to put my information to use. 🙂👍 Alternatively, I have some of my most common solar array setups pre-built here: shop.explorist.life/product-category/all-products/camper-wiring-kits/solar-charging-wiring-kits/

[@chrisbroom8418]

@@EXPLORISTlife Thank you for your help.

[@jprabago1714]

I have 3 panels connected in parallel, the total Short circuit current for the 3 panels is 34.14. And the maximum series fuse of my panel is 25amp. So i need to put an inline fuse of 25amp per panel, right?

[@EXPLORISTlife]

Yep!

[@CountryBoyMoto]

It sounds like fusing in parallel is just a good thing (cost vs possible repercussion)

[@EXPLORISTlife]

The voltage of a parallel wired array is rarely high enough to properly charge the battery bank. Series parallel or series is generally the better option.

[@CountryBoyMoto]

@@EXPLORISTlife I will watch your instructional videos “again” once my components arrive