12v battery/ 12./24v MPPT ~ 24v PV Panel
This question troubles the Old and Slow mind. I have a 24v/120w Cynergy PV panel. I would like to use it for duel purpose. For my 24v e/scooter and my 12v RV, not at the same time. The MPPT states (15...
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PT
I do not believe I said all Blue Sky controllers were cheap - what I said is that the one I had the misfortune of looking at had a "JUNK" MPPT tracking system with a user adjustable pot nothing more - to me that's cheap junk
A bit of a correction / explanation is needed for your earlier statement
"The higher the input voltage the more of the energy will be wasted as heat inside the controller--so it still behooves one to use lower voltages unless you wish to save on the cost of #4 wire to the controller from the roof."
The losses in a properly designed buck conversion stage is negligible at best with higher voltages, the advantages far out way any potential loss. Smaller more flexible wire, lower cost wires, easier to hide out of sight, far less line losses, P=I(squared)*R half the current 4x less line loss. Lijne losses at high current say 30 amp array current even with 4 awg wire can be 3 to 4% if running long lines - a proper buck conversion stage might have 1% loss difference between the input voltage range
I do not believe I said all Blue Sky controllers were cheap - what I said is that the one I had the misfortune of looking at had a "JUNK" MPPT tracking system with a user adjustable pot nothing more - to me that's cheap junk
A bit of a correction / explanation is needed for your earlier statement
"The higher the input voltage the more of the energy will be wasted as heat inside the controller--so it still behooves one to use lower voltages unless you wish to save on the cost of #4 wire to the controller from the roof."
The losses in a properly designed buck conversion stage is negligible at best with higher voltages, the advantages far out way any potential loss. Smaller more flexible wire, lower cost wires, easier to hide out of sight, far less line losses, P=I(squared)*R half the current 4x less line loss. Lijne losses at high current say 30 amp array current even with 4 awg wire can be 3 to 4% if running long lines - a proper buck conversion stage might have 1% loss difference between the input voltage range
