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Electronic Ballasts

Does that wiring diagram seem TOO simple? Why are they are only showing one wire to each end of a four pin fluorescent bulb?

Retrofitting a duel bi-pin (an F40CW, for instance) fluorescent tube fixture with T-8's and an electronic ballast requires an 'old-dog' electrician to learn new tricks.

Instant-start electronic ballasts require that the lamp tombstone sockets have both leads shorted together. Old-fashioned ballasts used to energize a filament on the end of the fluorescent to which required a two-wire circuit to each end of the fluorescent tube. Electronic ballasts don't work the same way. Both pins on the tombstone socket are not really necessary.

No doubt you've installed hundreds of flourescents in your life.  But, it's time to pick up the instruction sheet that you just tossed on the floor. . . . and read it.