of the spark plugs through the spark plug wires via the rotor and cap.
Figure 4. An ignition coil transforms a vehicle’s 6-, 12-or 24-volts,
into 15-20,000-volt impulses that fire the spark plugs. A coil
operates by creating an electromagnetic field, and the high voltage
impulse is created when this field collapses. “Loading and firing”
the coil is performed by the breaker points.How and why does an ignition coil load and fire? How does it conjure
up 20,000 volts when a vehicle only has a six-, 12-or 24-volt electrical
system? Should you be worried about messing around with 20,000
volts?
To answer the second question first, while the voltage is high, the
amperage is low, and the surge or spark only lasts for a moment. It isn’t
like 20,000 volts flowing out of a downed power line. Getting bitten by
this spark will make you jump and probably say a four-letter word, but it
won’t make you toast. It can make you bang your head against the hood,
or fall off a stool if you’re standing on one.
As to the first question, and without going into a lot of detail, an
ignition coil is able to produce 20,000 volts from six, 12, or 24 volts by