Fusing solar panel arrays wired in parallel.
Fuse individual solar panels or array.
First between the charge controller and battery bank second between the charge controller and solar panels and third would be between the battery bank and inverter to determine the fuse size needed between the charge controller and battery bank you simply match the amperage rating on the charge controller.
I oversized the cabling between the panel array and the controller to minimize any voltage drop from the panels but i m at a loss as to what size fuse or breaker i should use in this cable run.
Solar panel charge controller wiring intro solar panel charge controller wiring diagram and step by step guide for off grid solar power system wiring.
This means each series needs a fuse breaker placed in the combiner box as shown here.
Fuse you need at least one large fuse at the battery to protect the smallest wire you have connected to it.
There are many fuse wire gauge tables on the web.
Some panels have bypass diodes whose function is to bypass shaded sections of panels but you loose about 8 volts each time they kick in and your array wattage drops.
I also installed a solar charge controller inside the boat.
There are three different locations that we recommend installing fuses or breakers.
My question is about providing a fuse or circuit breaker for the output of the panels.
To understand how wiring in series works in comparison to how parallel wiring works let s think for a moment about how christmas lights used to work.
I assume this is so if a panel shorts internally the other panels don t pump all their current through said short and cause overheating.
In a parallel system a combiner box is used that holds the fuses breakers to each panel plus one or more combined fuse leading to the charge controller or grid tie inverter see figure.
If your panels are smaller than 50 watts and use only 12 gauge wires and 20 amp fuses are required.
Now in the case of 3 panels in series and 4 strings in parallel if one string shorts the max amperage to short is 39 12 which exceeds the 30 amp max current rating of the 10 awg wire.
Maximum power point tracking mppt charge controllers are for wiring solar panels in a series where pulse width modulation pwm charge controllers are used to wire solar panels in parallel.
