Brought to you by Water Star Motors 
Your Serene, Green Auto Repair TeamWritten by Henry & Lisa Carter
The charging system keeps the battery alive and kicking. Alternators, generators, and voltage regulators are the common components of your cars’ charging system.
Since the late 1960’s most cars come equipped with a 12 volt alternator with a built in voltage regulator.
What is the difference between an alternator and a generator? Simply defined: They both are turned by a drive belt and generate electricity, but they create different types of current. A generator makes Direct Current (DC) (same as the battery.) It then uses a mechanical regulator to control the amount of electricity that flows to the battery. An alternator makes Alternating Current (AC) (same as in your house at home.) It then uses an electronic regulator and diode assembly to convert the AC current to DC current.
Do alternators come in different sizes? While today’s cars all use 12 volts, the output or amperage may vary depending on your car. For a small car with fewer electrical components there are low amperage (35 Amps) alternators. On today’s bigger luxury cars there may be two batteries and an alternator putting out up to 150 Amps when needed.
What can you tell me about electricity? There are three basic components that describe (or define) electricity. The amount of electricity is measured in amperes (or Amps). In using a water analogy, amperage is similar to how much water is in the reservoir. The force or push is measured in Volts, similar to the water pressure. The other factor that is involved is Resistance. This would best be portrayed by the handle on a faucet. You can adjust the resistance. More water = less resistance, less water = more resistance. The relationship of these three things is defined as OHMS LAW.
Ohms Law states; the power available is Volts x Amps = Watts. Any excessive resistance will reduce the watts (i.e.; the amount of power available to work with).
Any extra resistance in your cars’ electrical system will eventually lead to some sort of problem. Slowing the flow of electricity creates heat at the point of most resistance. The most common cause of extra resistance is a corroded battery cable. Have you ever opened your hood and discovered a beautiful blue green ‘science project’ growing on the posts of your battery? (Looks something like mold.)This corrosion commonly creates resistance causing stress on your alternator and interferes with charging. This problem should be dealt with in a timely manner, for it may leave you stranded at the most in inopportune time.
How can I clean my battery terminals? An old home remedy for this is to clean the battery with Coke Cola or baking soda mixed in water and a tooth brush. CAUTION this colorful stuff is not for your skin or eyes to make contact with, and make sure you throw away the brush when done. Also rinse the battery with plenty of water to keep the ants away.
Other possible sources of charging system failure are; worn drive belts, fluid leaks on and into the alternator, loose electrical connections and a weak or low battery. Regular inspection and servicing of your battery, charging system and its components will lengthen the life of your alternator and battery.
Water Star Motors is at 318-A River Street, Santa Cruz, CA 95060. 831-457-0996
We want to answer your car questions through Rock, Paper, Car.
Send questions and comments to: Henry&Lisa@WaterStarMotors.com
