One of the most important aspects of the automobile is the Electrical System. Manufactures add new technology all the time but if you remember the basics, you won't have any problems. Remember don't make it any harder than it is and always remember the Basics
Some Basics in Electronics is always a good thing to remember
Some battery Basics
Types of Curcuits
Using the Digital Volt/Ohm Meter is Critical.
Installing Solderless Terminals
Some Electrical notes
VOLTAGE DROP
1. Voltage drop is measured with a voltmeter while current is flowing in the circuit
2. There will be a voltage drop across each resistor or load device
3. Voltage drop across each resistor load device will be different if the resistance of each load is different
4. Voltage drop across a load device equals its resistance multiplied by current flow
Series Circuits
II. A circuit in which devices that use the current (loads) are connected end to end so that the same current flows through each component
III. Series circuit laws – The current which flows through each load device is the same at any point within the circuit
A. A series circuit is one in which all components are connected one after the other like links in a chain
B. If an open exists at any point, the entire circuit is open and will not work
C. The total resistance in a series circuit is equal to the sum of all resistances in the circuit
1. Total series resistance must be more than the largest individual resistance
2. Series circuits offer the highest resistance to current flow (generally do not allow a lot of current to flow)
D. Sum of all voltage drops must equal source voltage
Parallel Circuits
I. A circuit which provides more than one path or branch for current to flow (if one branch is open, current will still flow through other branches)
II. Circuit Laws
A. Battery voltage is applied to each branch in the circuit
B. Total voltage drop across each branch equals battery voltage
C. Total current in a parallel circuit is equal to the sum of the individual branch currents
1. If resistance of any branch is different, current through each branch will be different
2. Current flows through path of least resistance
D. Total Resistance must be lower than any branch’s resistance
Series – Parallel Circuits
I. A circuit with current flowing in series AND parallel at the same time
II. Some heavy duty parallel circuits use a switch in series to control current flow to parallel branches of the circuit
III. Instrument lights are a series – parallel circuit
IV. Laws of series – parallel
A. An open in the series portion will disable the entire circuit
B. An open in the parallel branch will stop current flow only in that branch
C. Resistance of the load devices in series drops the voltage to the load devices in the parallel branches
D. Available Voltage for the parallel branches is whatever is left after dropping across the series portion, and will be available to every parallel branch.
Formula for Resistance in SERIES/PARALLEL
Rt = Resistance of series portion + Resistance of parallel portion
