Jkidd288
Member
A very important topic in the world of car audio is the inevitable issue of voltage drop and having the proper electrical equipment installed.
Im going to explain to you the most basic principles to any electrical system and why having an adequate electrical system matters.
First, lets define the three most important variables that make your system possible which are current, voltage, and resistance.
Current(I): the current through a wire is measured in amperage and is simply the flow of electrons through the wire. Think of water through a pipe or river.
Voltage(V): the voltage of a wire is simply the Electric Potential and is measure in Volts. Think of the pressure pushing the electrons or "water" down the wire.
Resistance®: the resistance of a wire depends on length, resistivity, wire guage, and temperature. Think of resistance as a dam in a river slowing down the current. Essentially, the flow of electrons is always the speed of light, resistance only truly limits the amount of current and has an effect on voltage as well.
Now that we have this defined, we can piece them together and we have the most important law of electricity which is Ohm's Law. Ohms Law states that current is directly proportional to the Voltage over Resistance.
I = V/R
R = V/I
V = IR
P(Watts) = VI
These are the four formulas to remember when we dive in about amplifier and performance as well as electrical and battery performance.
Now, all amplifiers really should be rated on how much current and they can push as well as how much voltage can be put to them. Lets say an amplifier is rated at 1,000 watts rms at 1 ohm @12.6volts, this means it needs 80 amps at 12.6 volts. If we raise the voltage to 14.6 volts you only need an equivalent of 68.5 amps. Thats a 15% difference in the amount of current required which reduces strain on the battery, amplifiers, alternator, and the car as a whole.
Now here's where the your increase in voltage makes the power increase as well, 80 amps at 14.6 volts gives you 1,168 watts opposed to that 1,000 you already had. Also the stability of the electrical is better and you wont have to worry about the battery becoming weak as its charge at the terminal is not suffering any significant drop really. Ideally there is no voltage drop but in reality there's always voltage drop.
In order to rid this drop as much as possible, one should note the length of the wire running along the car, the wire size, having enough current supply(batteries) and accommodate for higher temperatures - as this will decrease performance - by running multiple wires or reducing the length as much as possible..
First start with your alternator, this is the primary source for all the vehicles electrical needs, it will supply current as demanded but cannot supply more than it is physically capable of. It is impossible to have too big an alternator.
Next upgrade your Alternator's positive leads with preferably 0 guage and also upgrade your engine block to ground wires.
Now depending on your needs you may want to add a second battery but most definitely make sure you use a new battery along with the new alternator. If your battery supply is not big enough there will still be significant voltage drop. Use the largest wires your amplifiers will accept and the audio sustem should be complete.
Now, one last thing, there's a debate on using battery isolators between batteries. Well i've read my electric circuits book pretty thoroughly and also made an A in the class. If two batteries have a resting voltage between 12.6-13.0 volts which is where all 12 volt batteries will rest, there is no issue when wiring them in parallel. The only thing that will cause a battery to weaken the life of another is having two different terminal voltages. This is why having an Alternator that can keep them BOTH charged is crucial. If you like to park and play, monitor your voltage and try not to let the voltage drop below 12.6. If you can do all of these there's no need to waste money and time on the isolator because it will also cause a drop in voltage to the rear battery.
If you dont take these measures into effect, you will simply beat down the car's electrical and your equipment until it fails. And that defeats the purpose of having them.
Any questions?
Im going to explain to you the most basic principles to any electrical system and why having an adequate electrical system matters.
First, lets define the three most important variables that make your system possible which are current, voltage, and resistance.
Current(I): the current through a wire is measured in amperage and is simply the flow of electrons through the wire. Think of water through a pipe or river.
Voltage(V): the voltage of a wire is simply the Electric Potential and is measure in Volts. Think of the pressure pushing the electrons or "water" down the wire.
Resistance®: the resistance of a wire depends on length, resistivity, wire guage, and temperature. Think of resistance as a dam in a river slowing down the current. Essentially, the flow of electrons is always the speed of light, resistance only truly limits the amount of current and has an effect on voltage as well.
Now that we have this defined, we can piece them together and we have the most important law of electricity which is Ohm's Law. Ohms Law states that current is directly proportional to the Voltage over Resistance.
I = V/R
R = V/I
V = IR
P(Watts) = VI
These are the four formulas to remember when we dive in about amplifier and performance as well as electrical and battery performance.
Now, all amplifiers really should be rated on how much current and they can push as well as how much voltage can be put to them. Lets say an amplifier is rated at 1,000 watts rms at 1 ohm @12.6volts, this means it needs 80 amps at 12.6 volts. If we raise the voltage to 14.6 volts you only need an equivalent of 68.5 amps. Thats a 15% difference in the amount of current required which reduces strain on the battery, amplifiers, alternator, and the car as a whole.
Now here's where the your increase in voltage makes the power increase as well, 80 amps at 14.6 volts gives you 1,168 watts opposed to that 1,000 you already had. Also the stability of the electrical is better and you wont have to worry about the battery becoming weak as its charge at the terminal is not suffering any significant drop really. Ideally there is no voltage drop but in reality there's always voltage drop.
In order to rid this drop as much as possible, one should note the length of the wire running along the car, the wire size, having enough current supply(batteries) and accommodate for higher temperatures - as this will decrease performance - by running multiple wires or reducing the length as much as possible..
First start with your alternator, this is the primary source for all the vehicles electrical needs, it will supply current as demanded but cannot supply more than it is physically capable of. It is impossible to have too big an alternator.
Next upgrade your Alternator's positive leads with preferably 0 guage and also upgrade your engine block to ground wires.
Now depending on your needs you may want to add a second battery but most definitely make sure you use a new battery along with the new alternator. If your battery supply is not big enough there will still be significant voltage drop. Use the largest wires your amplifiers will accept and the audio sustem should be complete.
Now, one last thing, there's a debate on using battery isolators between batteries. Well i've read my electric circuits book pretty thoroughly and also made an A in the class. If two batteries have a resting voltage between 12.6-13.0 volts which is where all 12 volt batteries will rest, there is no issue when wiring them in parallel. The only thing that will cause a battery to weaken the life of another is having two different terminal voltages. This is why having an Alternator that can keep them BOTH charged is crucial. If you like to park and play, monitor your voltage and try not to let the voltage drop below 12.6. If you can do all of these there's no need to waste money and time on the isolator because it will also cause a drop in voltage to the rear battery.
If you dont take these measures into effect, you will simply beat down the car's electrical and your equipment until it fails. And that defeats the purpose of having them.
Any questions?
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