Suggested answer:
(1) Electric is typically used to refer to things that are powered by electricity, e.g.
...his electric bedside clock...
The electric drill had not yet been invented...
(2) Electric is typically used to refer to things that are produced by electricity, e.g.
(C) does not generate electric energy...
...preventing the passage of an electric current...
Although less common, electrical also has been used in similar contexts, e.g.
...engines which supplied electrical power...
(3) Electrical is typically used to refer to the use of electricity as a whole as opposed to other forms of energy, e.g.
The trouble is in the electrical system.
...Katie married an electrical engineer...
(4) Example of electronic referring to equipment in which the current is controlled by transistors, valves, and similar components:
Machinery, such as the electronic computer...
There are no occurrences of electronical in the corpus, which makes it an unlikely word form in English. Incidentally, it is not recorded in the "Webster Dictionary Online" either.
Read about adjectives ending in -ic and -ical here
Terminology: adjective
Dictionary: Webster Dictionary
