yes, you can connect two modules (of the same nominal voltage) in parallel to one controller.
no, blocking diodes will not be necesary.� the charge controller will provide that function, and the series overcurrent protection in the combiner box will further protect the modules, provided the overcurrent protection is sized appropriately to the max series fuse size of each module.
to do it properly, a combiner box with appropriate series string protection would be the way to go.� this box would go next to the modules and allow you to leave the array with one positive (ungrounded-red-), one negative (grounded-white-), and one equipment grounding (green) that would go to your pv disconnect then charge controller.
here is a schematic from a package of a system that is likely similar to yours (at least the array with two modules in parallel).� to see the schematic, scroll down to a picture of a cabin and click on it.
http://store.altenergystore.com/Kits-and-Package-Deals/Off-Grid-Systems-Cabin-Systems/Off-Grid-Cabin-Special-Pkg-1-170W-PV/p5692/cheers,
james
altE staff
