Expected watts from solar panels.

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I have acquired a Victron Smart Solar and so can now use the app to have a look at what the panels and battery are up to.
What is the typical wattage reading and Amps I should see from the solar if my 2x 90 watt panels connected in parallel are working okay? One panel almost new, other panel unknown age so out of interest would like to know if they are both still performing well?
 
You’ll never achieve maximum output unless the sun is directly overhead and it’s mid summer day

I’d suggest 150w maximum in the summer which would be around 10A
 
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Remember you will only get maximum current if there is somewhere for it to go. If the batteries are fully charged you might only see an amp or so. If you want to find out you could cover the panels then run the batteries down a bit then uncover the panels. Do this on a sunny day at noon. The readings you see should be close to the maximum but it may only last a few minutes depending how discharged the batteries were.
 
Remember you will only get maximum current if there is somewhere for it to go. If the batteries are fully charged you might only see an amp or so. If you want to find out you could cover the panels then run the batteries down a bit then uncover the panels. Do this on a sunny day at noon. The readings you see should be close to the maximum but it may only last a few minutes depending how discharged the batteries were.
Thanks. Battery fairly full and only seeing 18watts / 1.2 amps from solar today. Will drain battery down a bit over night.

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Slightly off topic this...
Just googled "Victron Smart Solar" and got this page...

20200913_200613.jpg


Clicked on the link circled in red and got this on my screen...

Screenshot_20200913-200055_Chrome.jpg

Anyone reckon it's safe to click the blue "update" button. Never seen anything like this?
 
Today I was getting 4.5 amps out of a 100 watt panel with an inverter running a laptop charger, 12v hair straighteners and battery under load showing 12.3v
 
Thanks for the reference points. I deduced one of my panels was doing nothing. Badly wired MC4 connector before Y fitting meant only one panel's juice made it to controller.
 
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Remember you will only get maximum current if there is somewhere for it to go. If the batteries are fully charged you might only see an amp or so. If you want to find out you could cover the panels then run the batteries down a bit then uncover the panels. Do this on a sunny day at noon. The readings you see should be close to the maximum but it may only last a few minutes depending how discharged the batteries were.

All lights and small fan on overnight and now all turned off and taken screenshot of readings at 9:50am before sun is properly above my panels. Can you explain the different Ampage readings from panels and battery? Thought the solar amps would be higher than battery?

Screenshot_20200915-094943.png

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The watts are the same so if the voltage changes the amps has to go the other way, Watts = Volts x Amps,

16.98x3.7=62.82

12.64x4.9=61.93

So other than a little bit of loss for possibly heat in the regulator some decimal rounding it balances.


Martin
 
As above. With an MPPT controller solar voltage will be higher than the batteries but amps will be lower. :)
 
DBK funflair Many thanks for the information. Needed to check all working okay before I pop MH back into storage and this new information screen whilst very useful, didn't make sense to me at first. (It did help me nail that I had a connection problem though, didn't notice I had not pushed the MC4(?) pins properly into the plastic plug surrounds).
 

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