Short Circuit (Parallel):

Whenever a parallel circuit becomes short circuited, the similar effect occurs as in a series circuit: there is a sudden and extremely large increase in circuit current that was display in the Figure.

Figure: Shorted Parallel Circuits

Parallel circuits are more likely than series circuits to develop damaging short circuits.  This is since each load is connected directly across the power source.  The resistance among the power source terminals is practically zero if any of the loads becomes shorted.  The resistance of the other loads keeps the circuit resistance from dropping to zero if a series load becomes shorted.