What do I need to connect two or three solar panels in series? Some sort of junction box? Also, just to make sure the positive from the controller goes to the battery monitor shunt and the negative from the controller goes straight to batteries? Where do I put the fuse? - Jack
In this diagram, notice how the positive of one panel goes to the negative of the other and so on. This is quite similar to wiring a 12 Volt battery from (2) 6V golf cart batteries. A series connection is really one circuit where all the current needs to go through all the items to complete the connectivity. Parallel connections offer multiple paths for current.
Let’s recap, a shunt is NOT a load. Therefore it does NOT have a positive or negative wire connected to it. Doing so would make either of the battery cables melt or perhaps blow-up your battery. A shunt is an inline device to be wired on the negative connection to the negative post of the battery. The fuse is located at the battery between the battery and the MPPT controller. - Jeff