Bob, etal,
That is not the purpose of having a condenser (or two in the case of a
dual point unit). Although the ignition coil is charged by DIRECT CURRENT,
it charges and discharge so rapidly, the circuit behaves similar to
characteristics seen with ALTERNATING CURRENT...in fact it is "seen" as a
square wave: on-off-on-off...
Consequently, there is a component of INDUCTIVE REACTANCE (XL (little L)
the opposition to the flow of alternating current or pulsating current by the
inductive reactance (ac resistance) of a circuit: this puts voltage and
current OUT OF PHASE.
The equation: 2 pi fL.....where f is in hertz and L is in Henrys
The consenser/s (capacitor/s) is/are chosen to RESTORE the phase
relationship of current and voltage, using CAPACITIVE REACTANCE, (Xc The
capacitive reactance (ac resistance) a capacitor offers to alternating
current or pulsating direct current.
The equation: 1over 2pi fC......where f is in hertz and C is in farads.
Inductive reactance and capacitive reactance are INVERSELY PROPORTIONAL
to eachother: THEY CANCEL EACHOTHER OUT...and that is the goal.
Jim Leach, PTC Seattle
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