diy solar

diy solar

Panels in series - how much loss??

skykidnv1000

Curious
Joined
Sep 18, 2021
Messages
14
I'm working with an MPP1012 all in one controller with 4 200W panels
Each panel individually tests about the same from a watts perspective on the system (130W at time of testing)
When I hook two panels in series, I get the increase in Watts as expected (230W at testing)
However when I add additional panels, the Watts seem to stay the same (Amps and Volts go up as expected )
With 4 panels (at testing time) I'm showing 80v, 8A and 280W
I expected the watts to me more, but understand the loss's involved.
How much should I expect??? I'm only running abut 50' of wire from panel to controller
 
"MPP1012 " Is it MPP Solar PIP-1012LVMS?
"I'm showing 80v, 8A and 280W" What is 8A reading from? Is that the battery charging current or PV panel current?

How are you adding the panels, all 4 panes in series?
What are the spec of the panels, I.E. Voc, Vmp, Imp, isc?
 
Last edited:
Yes MPP Solar PIP 1012LV
Right now its reading 15A (battery charging current) from the MPP panel
80V from the from the MPP panel
225W from the MPP panel
Panels are in series
Panel specs: Rich solar Voc = 24.3, Vmp=20.4v, Imp=9.8A, Isc=10.2A
 
After some more experimentation I see it is very load dependent as to what shows up on the MPP panel display.
It seems only to display the watts necessary for the current load, or battery charging requirements.
Right now my batteries are fully charged and the PV watts show in the 200's. As I add more loads the PV watts goes up and down depending on the load and/or sun availability. I'm guessing as I increase the load the PV watts will continue to increase on the display to some max amount from the panels accounting for the loss's from the connectors. wire length etc.
 
After some more experimentation I see it is very load dependent as to what shows up on the MPP panel display.
That would be the case for an off grid setup. In the case of a Grid Tie system the grid presents an infinite load and the inverter outputs the maximum it can convert from the solar production.
 
Back
Top