Voltage Drop (1 Viewer)

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In researching my intermittent start issues, I came across this article explaining voltage drop and the effects of bad ground connections. It's a worthwhile read for those of us still learning. What I couldn't figure out is if the age or use of the wire changes voltage/impedence/current. I understand corrosion and breaks will negatively effect the circuit.

Voltage Drop

Please post additional resources or experiences with bad grounds below.
 
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Wire age doesn't effect the impedance, but corrosion is more prevalent with age. corrosion occurs when two dis-similar metals touch, (like a copper wire and a tin/silver connector pin, or the steel frame of your truck) and is accelerated when current is running through the metals. Corrosion is often proportional to the current that the conductor is carrying, so your battery terminals will corrode alot faster than your radio power connector.

in terms of bad grounds... their are no 'bad' grounds, only high impedance grounds. A perfectly snug connector, or cable lugged to the frame will have an impedance of <1 ohm. this is sufficient when the impedance of the load is a couple hundred ohms or more. But when your wires are getting corroded, the impedance of the ground connection rises, and reduces the amount of power that is delivered to the intended load.

Mathematically, ( if you're into that sort of thing) Power can be:
P= current * voltage
or
P= current ^2 * Resistance
or
P= Voltage^2 / Resistance

in every case, when your ground connection is corroded or loose or whatever, you have a higher impedance. This higher impedance is robbing your intended load of power because the current has to flow through the corrosion to return to ground, essentailly consuming the power that you intended for the load.
 

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