During the "not so modern days," it was called a generator. As its name suggests, the
alternator turns mechanical energy into an alternating current (AC) electrical energy.
The battery keeps the engine working in an internal combustion engine. And then, the
alternator keeps replacing the power that is utilized by the battery.
Electricity is generated by an alternator when there is a change in the magnetic field
around a conductor. Most automotive alternators use a rotor or the rotary piston in a
rotary combustion engine where a rotating magnet inside the conductor induces the
And because of a voltage regulator, the conductors which are coils wound around an
iron core also allow the voltage of the current generated to be controlled. The rotor is
usually mechanically set in motion.
The size of an alternator is the usual determinant of its efficiency, which is very often
affected due to problems in the bearings, inadequate cooling by the fan or even copper
and iron loss.
Majority of the present day alternators operate at about 55 percent efficiency. But if
you augment its range, this conversion of mechanical energy in your car into electrical
energy can be increased.
During the time in memoriam, the alternator only had to power the lights and a horn.
But today, we have heating, stereos and fancy headlights that need much more power.
This is the reason why we have high-output and high-amp alternators, and most of
them are made with high-quality magnets, bearings and windings.
Technology has greatly evolved many of today's equipments. But despite such fact,
the alternator still remains a fairly simple piece of equipment and is relatively easy to
replace as compared to other sophisticated car parts.
The question is: How do you know when it needs replacement?
An alternator needs to be replaced if the battery does not retain its charge, even when
it is charged from an external source. Another sign is that when you hear a loud
grinding noise that seems to be coming from the region of the alternator.
A voltmeter needs to be invested to accurately detect if your alternator needs
replacing. It is actually used to measure the voltage and can get for a few dollars, but
it is definitely worth your money. And if were to take it to your automobile mechanic,
he could test it and tell you whether you should replace it or not - just make sure you
got the right mechanic.
So now you know how your Saab alternator works. The next thing to know is how to
protect and maintain it.