This is a typical part in the various solar panel manuals I have seen:
"Under certain conditions, a module may produce
more current or voltage than under its Standard Test
Condition's rated power. As a result, a module’s
open-circuit voltage and short-circuit current under
STC should be multiplied by 1.25 when determining
component voltage ratings, conductor ampacities,
overcurrent device ratings, and the**** size of controls***
connected to the PV output."
(***s added by me) From 3.0 here:
http://www.canadiansolar.com/down/en/Installation_Manual_of_Standard_Solar_Modules%20(UL)_en.pdf
