WHY are Nortons Positive Ground?

My head hurts, I will have to go down the pub now!

As an addition to what Dave said early Goldwings have two coils with two leads apiece. If you run plugs long enough they errode differently on each side, one from the center, one from the electrode. I've never noticed any difference in running.

It was just a tradition, with some very flaky "pseudo-science" invented to justify it. Another British peculiarity is that their airplane engines rotate the opoosite way to US ones, a tradition that still applies to Rolls-Royce big jets. I have no idea how that one started - it doesn't apply to other engines.

[/quote]

If you look at old tube circuits, the plate voltage was B+ (positive) and the cathode negative, the electron flow was from the cathode to the anode or minus to plus, this is theory and that is how tubes work, current will not flow if tubes are reverse polarized, a spark can and will occur wheter the center electrode is positive or negative, now the Brits having invented the tube must have felt compelled to make ignition systems comforming to his theories and that is probably why they used a positive ground :wink:

Jean[/quote]

I guess I was confused about your use of "electrons prefer", kind of like maybe sometimes the electrons flowed the other way. Actually I have seen tube circuits where the plate is at ground (positive ground) and the cathode is very negative like -250VDC. The electrons will flow just as good in that circuit as a slightly negative or grounded cathode and a very positive anode. Again, it makes the zener diode easier to deal with, but it was probably tradition too, the early Japanese electronics used positive ground too, especially in the early solid state stuff.

Dave
69S

The early Japanese stuff I saw was often copied from British equipment. Sometimes you would see redundant circuits which made you wonder if the copier had a good grasp, regardless they got it soon enough.

If you look at old tube circuits, the plate voltage was B+ (positive) and the cathode negative, the electron flow was from the cathode to the anode or minus to plus, this is theory and that is how tubes work, current will not flow if tubes are reverse polarized, a spark can and will occur wheter the center electrode is positive or negative, now the Brits having invented the tube must have felt compelled to make ignition systems comforming to his theories and that is probably why they used a positive ground :wink:

Jean[/quote]

I guess I was confused about your use of "electrons prefer", kind of like maybe sometimes the electrons flowed the other way. Actually I have seen tube circuits where the plate is at ground (positive ground) and the cathode is very negative like -250VDC. The electrons will flow just as good in that circuit as a slightly negative or grounded cathode and a very positive anode. Again, it makes the zener diode easier to deal with, but it was probably tradition too, the early Japanese electronics used positive ground too, especially in the early solid state stuff.

Dave
69S[/quote]

Most Zeners are made with the Anode on the stud, the one used by Norton is actually a reversed polarity zener. I don't think the zener had anything to do with the selection of a positive ground. The choice of early Japanese electronics having a positive common was due to the widespread availibility of germanium transistors, as soon as silicon transistors took over, then the common switched to negative.

Jean

Jean,

Yes, you are right about the zeners and the solid state stuff. I just didn't think there was any difference in a circuit if it was positive ground or negative ground, they really work the same.

Dave

Another tidbit of British electrical history...

In the early days of electrical power distribution, a switch was a hinged blade called a "knife switch". We've all seen them, exposed copper bars etc. The British convention was to make up off and down on, probably as arbitrary a decision as positive earth. Some bright American decided that if a switch should fall from gravity, it should fall to the off position for safety reasons. So the American convention was up on, down off. The Brits followed suit eventually.

Hortons Norton said:

I feel the reason there are so many negative feelings about positive ground is that we have seen many more devices with negative ground. This makes us positive that we must use negative as ground, Positive ground should not be seen as a negative. Positive has been used for many years without negative effects, And negative has been used also with positive results. :roll:

Click to expand...

Are you positive? (sorry)

Is there positive and negative smoke too? Maybe they are a different colour.

Dave

DogT said:

Is there positive and negative smoke too? Maybe they are a different colour.

Dave

Click to expand...

Don't try to throw a monkey wrench in this mess, there HAS to be both positive and negative smoke otherwise nothing would work, now what I can't figure out is: does positive smoke rise or fall :?: and does it work the same way in Autralia and New Zeland :?:

:shock:

Jean

Some of Mr. Lucas's notes should shed light on this subject. LOL LOL.

DogT said:

Is there positive and negative smoke too? Maybe they are a different colour.

Click to expand...

POSITIVE smoke will be RED, and NEGATIVE smoke will be BLACK (obviously!)

Positive smoke swirles the other way in the southern hemisphere.

Here's a non electrical engineer question, it will posibly be a dumb question to the rest of you boffins,,,,

When it was time to rewire my Mk3 I was intent on rewiring it negative earth, then I was asked why, what is the advantage?
I couldn't answer with a valid answer. (apart from led's )
So after many hours on the web I wired it positive earth as I could not find a good reason to change.

Question. Assuming this is a Positive Earth System .
When the positive goes to one side of a bulb (for example) and the bulb is lit as the other side of the bulb (negative) goes through the "made" (closed circuit) light switch, then to negative on the battery, is there less current going through the light switch than if it was a negative earth system and positive current was going through the switch before it went to the light bulb ??????

After the positive has done it's work by lighting the bulb and gone through the high resistance of the filament is there less current or "fizz" going through the flimsy switches ??

This theory was the only benifit my tiny over medicated mind could think of as to why positive earth was an advantage. (no fuses)

I stand ready to be heckled.

graeme

An electronic engineer answers.
No difference at all Graeme. Same circuit resistances, same voltage source thus same current flows regardless of polarity.
And yes, you must take the Coriolis force into consideration when analysing the smoke. Absolutely.

GRM 450 said:

Question. Assuming this is a Positive Earth System .
When the positive goes to one side of a bulb (for example) and the bulb is lit as the other side of the bulb (negative) goes through the "made" (closed circuit) light switch, then to negative on the battery, is there less current going through the light switch than if it was a negative earth system and positive current was going through the switch before it went to the light bulb ??????

After the positive has done it's work by lighting the bulb and gone through the high resistance of the filament is there less current or "fizz" going through the flimsy switches ??

Click to expand...

It really makes no difference, the electrical system works the same either way, as long as polarity sensitive items are connected correctly.

GRM 450 said:

(no fuses)

Click to expand...

You still need fuses.

yes, basic electrical rules
voltage can be + or -, current flows in the opposite direction of voltage
amount of current will not change regardless of the voltage's polarity

Thank you sirs,

and I did fuse everything, just in case.

Forever? How long just is that? Seems about as long as I have been married.

Are we not riding enough? Is that why this thread went on so long? Give me some time this winter and I'll be ready this spring.

Dave
69S