Farm Equipment - Positive ground ??

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Positive ground ??

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Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=202572
Printed Date: 22 Sep 2024 at 5:32pm
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Topic: Positive ground ??

Posted By: DougG
Subject: Positive ground ??
Date Posted: 04 Aug 2024 at 7:12am

Can someone please explain the concept of positive ground ? I remember years ago my Uncle and his friends talking about this- I beleive they had a JD B with this setup- seems crazy but Im sure someone thought it was a good idea

Replies:

Posted By: jaybmiller
Date Posted: 04 Aug 2024 at 7:18am

think it comes from British coal mines ,long, long ago.

they used DC electric power for equipment(trains and drills,etc. )

a positive ground reduced the corrosion factor

hay, that's what I was told....1/2 century ago......

generators can be 'flashed' to be either +ve or -ve ground....

When 'solid state' devices(aka transistors....) came out, it was easier to design/build 'negative ground' alternators,radios, etc.

I'm sure DK can explain far better..... !!!

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3 D-14s,A-C forklift, B-112
Kubota BX23S lil' TOOT( The Other Orange Tractor)

Never burn your bridges, unless you can walk on water

Posted By: DougG
Date Posted: 04 Aug 2024 at 7:54am

Thanks Jay, yup that what they were doing - something with the generator, seems like the JD B had a 6 or 8 volt system too?

Posted By: Phil48ACWC
Date Posted: 04 Aug 2024 at 7:56am

I've read, electrons are negatively charged and in a battery the electrons flow from the negative to the positive side. So in the early days of electric start cars, the thought was to hook the negative side of the battery to the starter to get better cranking. It turned out it didn't make any difference. Over time car manufacturers adopted negative ground connections. I believe Ford was the last US car manufacturer to go with negative ground. They didn't change until the late 1950's.

Posted By: steve(ill)
Date Posted: 04 Aug 2024 at 9:00am

Most systems befor 1960 were positive ground and most of them were 6 v systems. Thre is no difference at the generator, the wires, the starter or anything else... Basically all you do is connect the POSITIVE side of the battery to the tractor frame as a GROUND... and the NEGATIVE side of the battery goes to the starter switch / solenoid.. The generator is putting out 6 volts NEGATIVE as the output terminal is connected to the NEGATIVE side of the battery ..... when you switched the cables on the battery..

Phil and Jay have covered the WHY they did this.... Sometime around 1960 everyone started to switch over to NEGATIVE GROUND... When they gave up on generators and went to Alternators, that was the end of the POSITIVE ground for good.

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Like them all, but love the "B"s.

Posted By: DougG
Date Posted: 04 Aug 2024 at 10:49am

Thanks Steve!