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solar sizing

data from Victron Shunt to built system

I put in the shunt to get real data before just guessing. so i have some good data but not sure how to turn this data into sizing the right system for my camper. is there a good calculator out there that I can plug thus data into so I know what i really need?

chadd-warwick asked
kevgermany answered ·

1 Answer

Mix Match Solar components

Hi All ,

I have existing components , thrown in with a recently purchased boat. Unfortunately the components are a mix match of different manufactures. I hope to glean advice on how to install to make this system work .

Eventually I will upgrade to all Victron . But for now I have to make this work .

Component list :

- Victron BlueSolar MPPT 150 I 70 -Tr charge controller

- Xantrex Freedom invertor

- Xanbus System control panel SCP FGA 809 0921

- 8 Renogy RNG 100D SS 100 WATT SOLAR PANELS


Any advice will help .

Diagrams and pictures say a 1000 words .

Thank You Kindly


wind-sun asked
wkirby answered ·

1 Answer

Upgrading a solar flex 200 on a Springdale travel trailer

Have a 200watt panel on the roof and a Victron 15amp charge controller with two 24 group lead acid batteries. Looking to upgrade to eventually run the whole camper and the roof ac unit. It’s a 30 amp trailer. Not sure where to start. I’m trying to learn as I go. I would Imagine adding a 30w charge controller/ inverter would be a great place to start? I currently don’t have a inverter installed. Suggestions on how to proceed with upgrading ?

jlw201 asked
jlw201 edited ·

0 Answers

Correct sizing of solar panel for float charging

I am going to add a solar panel to my boat just for providing float charge to my starter battery (12v 240ah) and bow thruster battery (24v 240ah). I will use a Smartsolar 75/15 controller and an Orion 12/24 to step up to the 24v battery.

My question is this: what current do I need the panel to provide to enable float charging of these batteries? I'm think a 115w panel will provide typically 8 amps in the sun but rather less most of the day and, of course, nothing at night.

Not worried about bulk charging - the alternator will do that and these batteries will only discharge at start or when the alternator is running



rob-dean asked
kevgermany answered ·

2 Answers

Pairing panels with 150/70 smart solar mppt

Good day, I am looking at adding some panels to my house.

I am however struggling to understand the mppt charge controllers ratings from Victron data sheet.

I am looking at putting 6 * 460w panels.
Voc= 50.01

Vmpp= 42.13

Configuarion would be (2x3) so we would be running at Voc = 150.03 and Vmpt= 126.4

With a Smart Mppt 150/70 charge controller.

In the manual, it says the MAX solar voltage is 150 (Absolute max in bracktes). Now I need to try and understand. Does that mean I can run this panesl on this unit? My understanding is that the mppt controller when running wouldn't ever really let the voltage get that high.

I know Victron is generally pretty good at under specing In their data sheets and over-delivering in the product.

Do I run any risk with this setup?

dylan-hyslop asked
Anold Pande answered ·

1 Answer

Victron Smartsolar 100/30 - Overpaneling with these panels?

Can I use 2x of these panels in series on a Victron Smartsolar 100/30?

Polycrystalline STC rated at 260w
Peak Efficiency 15.76%
Number of Cells 60
Imp 8.5A
Vmp 30.7V
Isc 9.01A
Voc 37.8V
NOCT 45.7°C

offroad asked
kevgermany commented ·

1 Answer

Do I need a DCDC charger using just a solar MPPT?

Do I need a DCDC charger using just a solar MPPT?

4WD canopy and I want to try 100% solar charging without using the car alternator

Battery is a single 110ah lithium battery

Solar panels have yet to be purchased but I want to buy a single fixed panel approx 350W, hardwired, and a 180W blanket. When I run them both, via a switch I expect to run them in series as I understand this is the most efficient option for unbalanced panels.

Is there a 'perfect' sizing for a Victron MPPT and panels?

Peter asked
kevgermany commented ·

3 Answers

PVsyst Simulation

Hi All,

Have any tried simulating the energy yield of the system using the PV system with Multiplus, Bluesolar charger on the pvsyst ?

Earl asked
Kendall commented ·

1 Answer

PVSyst Victron OND files

Hi all, seems there's is no such info available (OND files) to upload Victron products data base to PVSyst. It turns that there is a lot of demand on those products but is not possible to run simulations with out data.

alan-gonzalez asked
Kendall commented ·

0 Answers

Exceeding MPPT wattage limit

Yes, I know this is related to other questions/posts, but I need some clarity. I have four 340 watt (Hyundai HiS-S340Ti) panels, and 1120 ah 12 volt DIY battery (LiFePO4) on & in my travel trailer. My inverter/charger is the Victron MultiPlus II 120x2 12 volt, the charge controller is a Victron MPPT 150/100, and pretty much everything (except for the DIY batteries/BMS) is being managed by the Victron Cerbo GX. Yes, I wish I could have gone with a 24 volt system, but the MultiPlus II only comes in 12 volt, at this time - Victron, are you listening? With the four panels in full/direct sunlight in Arizona in mid March, I'm making 7.5 kwh per day, and consuming around 7 kwh/day - yeah, don't judge me :). I have the panels in a 2s/2p configuration. I want to add two additional panels, since it was my original plan and the cables are already up there - two of the six panels were destroyed in shipping. But, I'm concerned about the max wattage limitation of the MPPT (1450 for a 12 v system). I realize I'll only be clipping/exceeding capacity at the peak of the day when the sun is high in the sky provided I'm in a very clear and sunny environment - and that it a real possibility from time to time. Most of the time, it will stay under that - especially on cloudy days (excluding cloud edge effect), and in places where I have some blockage. Currently, at the peak of the day in AZ, I'm generating just over 1000 watts - Vmax around 85 volts. I just want to be able to keep the system breaking even, or providing a net gain, when I'm in the forest and/or experiencing a lot of clouds. At present, like I mentioned, I'm making only slightly more (about .5) kwh more than I'm consuming in an almost ideal solar generation environment. That said, how big of a risk of destroying something would I be taking by adding the two additional panels in a 2s/3p array? I'm considering getting/making a cover for the extra two panels, when I feel there might be a risk of exceeding capacity, but I'm sure I might miss/forget to put it on occasionally. So, again, how much of a risk would I be taking to add the two additional panels? How fragile are these MPPT charge controllers? Do they frequently burn out when input exceeds the max wattage?

lightful-mind-vet asked
lightful-mind-vet commented ·

2 Answers

Combining different size solar panels on camper

Hi all!

I currently have 2x 175W solar panels from Victron on the roof of my camper (Vmpp = 19.4, Impp = 9.03, Voc = 23.7, Isc = 9.89). I have them in series connected to a 100|30 MPPT from Victron. I have limited space on my roof but would like to extend my grid with one or two 55W panels (Vmpp = 18.8, Impp = 2.94, Voc = 22.9, Isc = 3.22). What would be the best way to connect them to my grid?

I understood that It is not advised to mix different panels - especially in series (high-efficiency loss), but parallel should work (with only a slight loss), right? Or am I missing something? Could you help me sort out the right method in case of:

  1. 2x 175W + 1x 55W
    Can I put all the panels in parallel and still run the same MPPT controller, or do I need to put the single 55W panel on its own controller. If so, which one should I go with (hopefully able to use with the same app).
  2. 2x 175W + 2x 55W
    Should I parallel them all or serie-parallel (175Ws and 55Ws separated) and run them on the same MPPT controller, or do I need to run both sets from their own controller? If so, which one should I go with (hopefully able to use with the same app).

I highly appreciate your help.



durovenia asked
kevgermany commented ·

1 Answer

2 x 350w 12v flexible solar panels


I am about to buy 2 x 350 12v solar panels for my boat to charge my house batteries.


I have no idea what I am doing but I assume I need to buy a regulator & would also like a shunt.

should I just buy the biggest regulator Victron sell ?

I’ve been caught a few times with flat house batteries so I want to get lots of solar to keep them charged & charge them fast when flat.

my boat is a 27ft sea ray. It currently has 2 x 100ah house batteries but I will probably upgrade these as well .

I have read about working out how many amps the boat uses by testing everything 1 by 1 . But not done that yet. Should I do that first ? Or just get lots of big stuff?



businessjett asked
JohnC answered ·

2 Answers

solar array advice

Hi just wondering what would be the best solar array to put on my boat.
i want to put 4 panels on the rear of my boat it has a 12volt dc power system.
i have a Victron SmartSolar MPPT 150/70-Tr series up panels no problem.
please has anyone got some suggestions

rod-clark asked
wkirby answered ·

1 Answer

Connecting an older solaredge inverter and then adding future PV


I'm looking to purchase a Multiplus II - GX, 5000, which I would plan to use with 2 banks of 2 Pylontech 3000C batteries.

We have an existing solaredge inverter limited to 3.2kw output, about 5 years old. Do I understand correctly that I can't put this on the backed up AC side?

In relation to the above, does the factor 1 rule include generation on the non-backed up side - I don't think so from reading about it, meaning that I can add up to 5000wp on the backed up side at a later date - again with another SE inverter due to partial PV shading (keeping my existing solaredge inverter on the non-backed up side). Is my understanding correct?

Thanks in advance,


g1234 asked
wkirby answered ·

1 Answer

MPPT 75/15 - not charging at high battery voltage

Hi all - happy new year.

I have a setup using the MPPT 75/15 to charge a LiFePO4 (12,8V) battery. My load is a low power LED panel for my garden.

Unfortunately I don't see the charger actually charging the battery even though pv voltage increase to Vbatt+5v. See attached photo. Would you recommend a panel configuration with higher voltage potential? In my area the light these days is very low. Would a panel of same size but with a higher voltage potential (i guess more panels in series) allow me to start charging even though we have these low light conditions?

I also had three similar setups with different loads. The one with the highest consumption started charging before the others. I believe this could be due to the lowered Vbatt of this one? They were all in the same area.



Thank you :-)

niive asked
niive commented ·

2 Answers


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