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Topic: Solar check (Read 777 times) previous topic - next topic

Solar check

Seems like I may have some panel issues - I'm just not developing enough Voltage these days. I have three old BP 50W panels and a 30 watt 'something else' - tied to a Blue Sky 25iX MPPT controller. On a full sun day I can barely get 2.5 amps. Last year, 7-8 amps was no problem.
I've got my eye on a pair of Kyocera 135W panels if one or more of this group is acting up...
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Solar check

Reply #1 –
In a bright day, cover a panel with a blanket or towel to see how it affects total amps.  Also check all wire connections.  Because of voltage drops, largest cable size should be used.  Put a volt meter on each panel without wires connected to eliminate wire shorts. We have 4 panels, two of which are 135 Kyocera and they work fine.

Re: Solar check

Reply #2 –
I had a similiar problem, turned out to be a loose connection at the control box.
David in VA
1994 Unihome Grand Villa U280

Re: Solar check

Reply #3 –
I found two slightly loose connections - one in a panel junction box (showed some signs of overheating) and one at the charge controller. All connections in the panels redone with Stabilant22. Somewhat of an improvement. I think I will probably pick up a 135W after this trip and add it in.
All the panels are at or close to their open/no load Voltage. Officially, they are actually all Siemens panels circa 96. 3 X 48W (black cells) and one slightly smaller 43 watt (blue cells) - looks like it was added later. So a total of 190W.
Theoretically I should be getting 7 to 8 amps.
I also redid the house battery connections with Stabilant. I haven't found where the solar wiring taps into the house circuit yet...
The selected media item is not currently available. Dave Head & Megan Westbrook
Titusville, FL - The Great Outdoors
'98 270 buying this month
Toad is a 2018 F150 XLT

Re: Solar check

Reply #4 –
You mention all panels are near their open circuit voltage.  Solar panels come in different voltages and the mix would be better if all were designed at same voltages. Common are 21 volts open, 17 volts with load.  Since you did not install these, you may want to tweak your MPPT controller for peak amps.