The breaker on the Z1000 is connected to the common side on both the 14V accessory terminals and the 20V barrel jack, so a short between either output's hot and common will trip the breaker. The unprotected route is between both hot connections. Shorting the hot of the barrel jack to the hot screw terminal will give you a 50amp+ short circuit with no breaker/fuse. If your brick is wired "correctly" this is a somewhat unlikely short. If yours is wired the same as the one I bought, however, it is much more likely, and becomes a problem. "correctly" wired or not, I recommend placing a 8-10 amp fuse between the hot accessory terminal and your load if you are also using the 20v output. This fuse should never blow, but in the event of an unlikely short between hots, it could keep you from a catastrophic failure.
JGL
