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Modern vehicle ignition systems use a negative ground system.
The reason some older vehicles used a positive ground system was because their manufacturers did not realize that metal erosion caused by sparking causes the center electrodes of the engine's spark plugs to be eaten away by the sparks if that electrode is connected to the negative side of the ignition coil's high tension output.
Such erosion can quickly make the spark-gap too large, causing late ignition problems which can seriously reduce the power output of the engine.
So, when using a positive ground system: a) the spark plugs had to have their spark-gaps adjusted every one or two thousand miles and b) the lifetime of the plugs was only around 5,000 miles or less.
Explanation
It is a fact of physics that, after millions of sparks, due to metal erosion there will be less metal on the electrode that is connected to the negative side of a dc (direct current) ignition coil.
So the center electrode of a spark plug will not erode away due to sparking if it is connected to the positive side of the ignition coil's high tension circuit and will erode away if is connected to the negative side.
As the spark plug's outer casing is much larger in area than its center electrode, if it is connected to the negative side of the ignition coil's high tension output, the erosion of the outer casing caused by sparking is hardly noticeable and this fact has the additional benefit that the spark-gaps of the plugs hardly ever need to be adjusted during their lifetime which, nowadays, can be well over 20,000 miles.
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In which vehicle positive ground system available?
VOLKSWAGEN
Why negative control is adopted in DC system And why DC circuit breakers are kept at the negative side?
The answer is: They are not. Whosoever told you that is off his meds. Alternatively, in some special applications there may be a reason for it. Many DC systems use a common ground where the loads are encased in the ground (like starter motors). Thus all breakers are positive, but some don't. If the loads don't care about polarity and the positive and ground are not common (like with a metal chassis), positive and negative is irrelevant.
Why did automakers switch from positive ground electrical systems to negative ground electrical systems?
negative ground systems have always been in use but some chose to use positive grounds as wires were poorly insulated and suffered from corrosion on negative earth systems but positive earth systems did not suffer as badly to corrosion (i heard somewhere Henry ford came up with the positive ground idea cant say for sure) in recent times insulation is greatly improved and with bridge rectifiers instead of contact rectifiers which caused more uneven power flow to the battery most decided to use the same system putting everything on negative ground for simplicity but you will always have one oddball who uses positive ground just for the sake of being different
A regulated dc power supply contains three terminals.positive negative and ground.a positive terminal for positive connection a negative for negative connection What is the use of ground terminal?
Grounding terminals are used to connect the electrical equipment or wiring system to the Earth. It's purpose is to reduce the risk of electrical shock in the event of a fault current. In most homes, the wiring system is permanently grounded to a metal pipe that connects to an underground water-supply system or to a metal rod that has been driven into the ground.
Do logic circuit have a polarity?
A: ABSOLUTELY Vcc must always be positive to ground reference. That does not means that it will not work if Vcc is at ground and ground is -5 volts. both situation are valid.
Does a 2002 Oldsmobile have a positive or negative ground system?
The system is negative ground.
Is a 1947 Oldsmobile a positive or negative ground system?
it has a negative ground system.
Is red positive or negative on a battery?
red is positive on a negative ground system
Does the farmall A have a positive ground electrical system?
Yes, this tractor has a positive ground system. It may have been retrofitted to 12 volt negative ground over the years though.
How do you jump a positive ground system off?
+ to +- to -+ to +- to -
In which vehicle positive ground system available?
VOLKSWAGEN
Is your 1996 suburban battery a positive or negative ground?
The Suburban has a negative ground system.
Is the battery on a 1983 380sl a positive ground?
I doubt it but I am not 100% sure. It is unlikely in 1983 BMW was using a positive ground system. You can easily find out. Trace the negative battery cable and see where it goes. It is is attached to ground then it is a negative ground system.
Do 1949 dodge pickups have positive ground?
If the 49 dodge truck is still on it's original 6 volt electrical system it is positive ground. All 6 volt auto systems are/were positive ground. All 12 volt systems are negative ground.
Is the battery in an Sl500 battery positive or negative ground?
Batteries are neither positive nor negative ground. It is the circuit itself that determines the common ground. For example: If I have two circuits, one needing 6vdc negative ground and the other needing 6vdc positive ground, the battery would be installed the same way in both circuits (positive terminal on the battery to the positive connection in the circuit, regardless of whether the circuit is positive or negative ground). The reason for labeling the ground as Positive or Negative has more to do with how the circuit is wired up, than the actual voltage source. The explanation for that is beyond the scope of this answer.
Can you hook a negative ground unit to a positive ground system?
Make sure thatit is isolated from other electrical components
How do you tell if a car has a negative or positive system?
Post the year, make and model of the vehicle (in new question) and one of us can tell you if it is negative or positive ground.
