diy solar

diy solar

Low harvest problem

My setup is:
450W x 10 panels in series
Voc = 49.6V, Vmp = 41.0V
I have an MPP Solar 5048GK. Max Solar Voltage or Voc is 500VDC.
Iiih, the voc of the panels is dangerously approaching the Vin max of your SCC
If you catch a cold very sunny day, you may be above the tolerances.
If Y where you I would rather use a 5S2P configuration, or a SCC that accepts 600V Vin.
 
Iiih, the voc of the panels is dangerously approaching the Vin max of your SCC
If you catch a cold very sunny day, you may be above the tolerances.
If Y where you I would rather use a 5S2P configuration, or a SCC that accepts 600V Vin.
Despite the opening, I don't think they actually have a 10s system. They wrote this a bit further down:

New info. Installer confirmed that panels are connected in 2 parallel strings of 5.
When they currently have is a 5s system with 5 panels doing nothing / not connected. That fits with the actual production they are seeing.

5s2p would work just fine.
 
Taking a break from the discussion to say thank you to all who have contributed lots of helpful thoughts and ideas. Hoping to continue. :)
 
View attachment 100745
I'm talking about this.

So I'm seeing Max 60A, Default 30A. Not sure what this means. I know Max is max, but what is Default?

More info. I've only seen max 30A battery charging when charging from PV. But when charging from line, I've seen battery charging go up to around 50A.
 
The 'Default' setting is what is preset from the factory, but it can be set to other value up to the max per customer's need.
My MPPT Solar has 80A (60A default) solar charging and 60A (30A default) utility charging so I can charge my batteries up to 140A if I want to.
 
So I'm seeing Max 60A, Default 30A. Not sure what this means. I know Max is max, but what is Default?

More info. I've only seen max 30A battery charging when charging from PV. But when charging from line, I've seen battery charging go up to around 50A.
I've checked the manual and it doesn't list the setting for the battery PV charging current, only mains. You need to check on the inverted itself or in the manual that came with it.
In the manual it has only this:
02 - Maximum charging current (Max. charging current = utility charging current + solar charging current)
11 - Utility charging current
From the manual it looks like the PV charging current cannot be set.

I think it's time to call your installer.
 
#02 setting: Maximum charging current: To configure total charging current for solar and utility chargers. (Max. charging current = utility charging current + solar charging current). Max is 80A total.
#11 setting: Maximum utility charging current Note: If setting value in program 02 is smaller than that in program in 11, the inverter will apply charging current from program 02 for utility charger. Max utility charging is 60A.
The solar charging current will be affected by the setting of #11 setting.
I.E. you set #2 to 80A, #11 to 50A, that means batteries will get 30A from solar and 50A from utility.
So try setting #11 to 2A, #2 to 80A and see what happen.
 
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Update: I was finally able to get my panel connections tested again. It turns out that one string in my 5s2p setup was not functioning. The MC4 connector was plugged in but the metal pin inside did not make good contact. It is now plugged in correctly and I'm now seeing much much better harvest. I was not considering this option earlier because I already had the connections checked once and the guy told me that the continuity testing showed no problems. ;-)

Thank you to all who help with ideas. I appreciate it very much!
 
Glad to hear you found the cause of the problem, this is where DC Clamp-on Amp meter is good for troubleshooting the issue.
 
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