I'm not an expert, but I can offer some real-world data. We use a Blue Sky 2512iX with 216 watts of Kyocera panels
(1x130, 2x43). The panels are mounted above the bimini
, with space underneath for airflow. Ours are wired in parallel so that shading doesn't effect the entire circuit. We ran 12-gauge wire from the panels, through the water-tight through-deck fitting, to a set of terminal posts. Then #4 cable to another set of terminal posts adjacent to the Blue Sky unit, mounted inside the nav station. Then #12 into the Blue Sky unit itself.
Within a couple of hours after sunrise we see 12.5 amps of charge from the Blue Sky unit. This is the panels' rated power, meaning that the MMPT controller is stepping the voltage down from roughly 17.5 to 13.5 with minimal loss of current
. We often see 13.0 amps on a cool day. This appears to confirms Cal40John's point that parallel wiring
is adequate for most 12V systems, and you don't need to wire in series to realize the benefits of MMPT.
By the way, we use the Blue Sky remote
display, mounted next to the Link 1000 at the nav station. By comparing the two displays you can instantly assess the solar charger
output (on the Blue Sky remote
display), net battery
charge (on the Link 1000 - actually this is simply current
flow across the battery
bus), and electrical system consumption
(the difference between the two).
Hope that helps!