[P @ F]

Well if those readings of 13.5 and 13.3 are at rest without the engine running then it looks like you have it cracked too !

I was getting concerned when i was getting readings of 13.2 at rest , then in the morning seeing that it had dropped back to 12.9 , but that is seen as full , but then you have the drive to the first job , which is in my case at least 5 mile , but most of the month is 10 mile , and that will boost them right back up again .
I am getting to the point already where im feeling that i dont even need to check the voltage , maybe getting a little cocky if you like .
My test is coming soon , large commercial retirement home that takes about 5 hours straight , the ideal situation would be a poor day of solar , being that the van moves only once for 100m tops i would then see to what extent the alternator puts juice back into the battery , if i get home on this day with 13.2 and it doesnt drop stupid amounts over night then that would be what i consider to be the setup i have been looking to achieve , wish me luck !

And good luck with the MOT on Friday , its always one of them malteser arse moments on the calendar 

[nathankaye]

Well if those readings of 13.5 and 13.3 are at rest without the engine running then it looks like you have it cracked too !

I was getting concerned when i was getting readings of 13.2 at rest , then in the morning seeing that it had dropped back to 12.9 , but that is seen as full , but then you have the drive to the first job , which is in my case at least 5 mile , but most of the month is 10 mile , and that will boost them right back up again .
I am getting to the point already where im feeling that i dont even need to check the voltage , maybe getting a little cocky if you like .
My test is coming soon , large commercial retirement home that takes about 5 hours straight , the ideal situation would be a poor day of solar , being that the van moves only once for 100m tops i would then see to what extent the alternator puts juice back into the battery , if i get home on this day with 13.2 and it doesnt drop stupid amounts over night then that would be what i consider to be the setup i have been looking to achieve , wish me luck !

And good luck with the MOT on Friday , its always one of them malteser arse moments on the calendar 

If i remember I will take battery readings in morning and see what they settled down to.
All the best with the final test then, might be a pack lunch day with engine running for half hr whilst ur eating to perhaps give an extra boost

[P @ F]

Nah mate , i like to live life on the edge 
Im hoping its overcast and dull to be honest , now that would be a true test you see !
As it is so far solar intake has been dire , mostly 10 Wh per working day lately , and the battery has not needed the bench since 15th Jan , Im not that brave though as will have my old van battery stored in my pump box should the worst happen i still get home

[Spruce]

Nah mate , i like to live life on the edge 
Im hoping its overcast and dull to be honest , now that would be a true test you see !
As it is so far solar intake has been dire , mostly 10 Wh per working day lately , and the battery has not needed the bench since 15th Jan , Im not that brave though as will have my old van battery stored in my pump box should the worst happen i still get home

10 wh isn't even one amp; its 0.83 amps.

[P @ F]

Nah mate , i like to live life on the edge 
Im hoping its overcast and dull to be honest , now that would be a true test you see !
As it is so far solar intake has been dire , mostly 10 Wh per working day lately , and the battery has not needed the bench since 15th Jan , Im not that brave though as will have my old van battery stored in my pump box should the worst happen i still get home

10 wh isn't even one amp; its 0.83 amps.

What !!!!
What is the conversion Spruce , the app has changed it all for me , with the meters it was easy , i had amps in and amps out ,
Now i only have W in Wh in and nothing for out , via app anyway .
Looks like i need to do some conversion now 

[P @ F]

It does make sense though as i was moaning when winter came  that i was getting less than 1 amp in all day from a possible 6.75 amps per hour

[P @ F]

Bit of panic there !
So every 10 Wh is 0.83 Amp
Im going to need 50Wh to run my pump for 1 hour then , at a draw of about 4 amp which is usual for me ?

[nathankaye]

My leisure battery, though everything connected to it is turned off once I've finished work is also showing 12.9 this morning after resting all night

[P @ F]

Yes mine is pretty much the same !
Way better day of solar today , had 50Wh in which is just over 4 amp .
I only had 9 go out so the alternator must have put at least 5 back in too !

[Spruce]

I stumbled across this today.

https://www.youtube.com/watch?v=1qD3mN8VotQ&t=9s

https://www.gonewiththewynns.com/Sailboat-Solar-Series-Parallel-Shading

So maybe if you have 2 panels you need to have 2 MPPT controllers to ensure that 1 shaded panel doesn't 'kill' the other..

[P @ F]

Dont think you can run 2 mppt with series can you ?
And with parralell as they work independantly it doesnt require 2 as the feed from the good panel will just go in with the feed from the bad , im not really sure on it really .
I have not really had a problem with shading yet , depending on where i can park i am either in the sun  or not , not much i can do about that side of things .
As the solar is getting a bit better now i will have another look at series and parralell again , it will be easier now that i have them quick connectors , it was always a chore before with terminal blocks !

I will check when the sun is out again how the shading test goes with my panels , a nicely folded microfibre and my pole should do the trick !     

[Spruce]

Dont think you can run 2 mppt with series can you ?
And with parralell as they work independantly it doesnt require 2 as the feed from the good panel will just go in with the feed from the bad , im not really sure on it really .
I have not really had a problem with shading yet , depending on where i can park i am either in the sun  or not , not much i can do about that side of things .
As the solar is getting a bit better now i will have another look at series and parralell again , it will be easier now that i have them quick connectors , it was always a chore before with terminal blocks !

I will check when the sun is out again how the shading test goes with my panels , a nicely folded microfibre and my pole should do the trick !   

You're right. You can't run 2 controllers if the panels are wired in series.

I was thinking more about Nats setup with one panel angled toward the sun and the other facing the opposite direction. I wondered if the 'shaded' panel (the one not getting the fully rays of the sun) was pulling down the other panel exactly as these 2 yachties found with blocking just one cell on one panel. Shading the one single cell 'killed' the output of both panels.

The installers who face panels on different sides of the roof, say facing east and the other array west, split the array into 2 different sections with an individual controller/inverter for each array.

Your panels are both flat so this shouldn't be an issue for you Rich.

.

[nathankaye]

I am seriously considering running 2 mppts.
The reason being;
On each panel I can see how much wattage/ampage is being produced, from that i decide which way Im running my panels. Either in series or parallel.
So im averaging 20v on one panel and 10 on the other. Now if i turn these panels on individually my MPPT controller will confirm this input before it brings it down to about 14v.  Yet, in this example if I turn both panels on, i expect the MPPT controller to confirm the initial input at 30v.  It doesnt, it shows at 20.   Now as of yet I havent the dongle to see specifics but it would appear that its only taking the strongest input.

[P @ F]

I did a bit of testing today as the weather was pants , totally overcast with light drizzle, i thought i would retest my reason for being in series during the no sun times .
First i had the full 120w  of  panels in series , this gave me 5w.  =  1/24
Then i had the full 120w  of panels in paralell ,  this gave me 3w. = 1/40
Then the 80w on its own , i got 2w.  = 1/40
Then the 40w on its own  , i got 0w. =  Feck/all 

So that for me reconfirms that series is the way to go during these times , this is obviously when having the MPPT comes into play , i had averaged 30v over the day , so 15v of overvoltage must have been the boost i got .

I think i need to do the same on a sunny cloud free day now , just to be sure on both counts .
The shading aspect as i say is not a big concern for me , if i have to park in bad light so be it , after all i am out there to clean windows not harvest free energy , more so now that alternator results are so good alongside the solar .

I will do the shade test on a sunny day though to to see how i am affected in series/paralell . 

[P @ F]

Nath , how is your alternator performing now its in the mix , as much as i hate to say it , i think that i am getting more benefit from the alternator than i am from solar 
Although , the alternator is useless if you are parked up , so it is the best of both worlds having both sources .

[nathankaye]

Nath , how is your alternator performing now its in the mix , as much as i hate to say it , i think that i am getting more benefit from the alternator than i am from solar 
Although , the alternator is useless if you are parked up , so it is the best of both worlds having both sources .

Agree with you, having both during these not so good days is beneficial.
I checked my van battery yesterday to be sure it was ok, after resting 24hrs and it showed 12.6. So today i didnt use the alternator and checked my battery not long back and its resting nicely just over 13v.   Thankfully quite sunny here in donny so i didnt do too bad from solar. My leisure bat is about 12.9.

Just a question about ur mppt.  On mine, it shows the source input in volts, so if i turn one panel on it will show 20v and after about 30 - 40 seconds it will reduce the volt to 14.  Is this normal?  Im guessing it is from what ive seen on some videos.
But my concern is, when i turn off that panel and turn on the 2nd panel which may show 15v at the time.   When i turn both panels, im thinking the MPPT should show 35v before dropping the volt.(?)   but it doesnt. It will just show the strongest voltage.  Does this mean its blocking the extra 15 from the 2nd panel altogether ??
Because if not I should be yielding more from the MPPT and meter after it,  than the meter before the MPPT

[P @ F]

Are you wired paralell when this is happening ?

[P @ F]

You are wired paralell aint ya !
I see what you are doing matey 

If you are in paralell , only the highest voltage from  1 of the 2 panels will be recognised by the MPPT , so if you have 20 from one  and 15 from the other only 20 will go to MPPT this will then get dropped to the 14/15 that is needed to charge the battery , the other 5 or 6 then gets coverted to extra amps and sent to the battery.

If you are set in series , the combined voltage of the 2 panels gets recognised , anything from 0 to 48 volt i believe , so my series system today was taking in  around 35volts , 15 went to charge the battery and the other 20 got converted to amps by the MPPT and then got sent to the battery .

MPPT is only really a real benefit when you have a fair amount of overvoltage hence why series is better in the gloomy weather , it can work better to have paralell when you have sun because you are grabbing the higher amps from the word go without having to worry about voltage so much .

I think Spruce put a vid on this thread showing that your model of MPPT used a fair lump of power to actualy get the over voltage conversion going , it may well be worth looking back and watching it again (Solar shed guy) 

[P @ F]

See , look along  the Vmax columb , 15 went to battery , the rest would have been converted by MPPT .

[P @ F]

Here you go

https://www.youtube.com/watch?v=YowgBCl1F1I