Positive or negative earth

Bill from Scotland · Dec 28, 2015

Just wanted to check if Im correct, are late 50's early 60's tractors such as Case, JD and International positive earth. When did most trurn to negative earth?
Bill

Tx Jim · Dec 28, 2015

JD changed from + to - earth on their 12 volt system tractors as a general rule when an alternator was factory installed which was Fall of '68 for '69 yr model. I'm referring to tractors built for sales in N America. I need to research tractors built for European sales to give correct answer. I don't know about other brands you inquired about.

Bill from Scotland · Dec 28, 2015

Sorry i should have said its on the US tractors im interested in. Case 900 and International 660 in particular.

Eagle Beagle · Dec 28, 2015

I have had some luck in the past verifying which way it was new by looking at the parts book if you have one. Often times the battery cables are identified by length.

CNH parts store online, I think, will give you your answer.

Beagle

paul · Dec 28, 2015

Generally when they changed from 6v to 12v, they went from positive ground 6v to negative ground 12v.

I think a few of them ran positive ground 12v with generators, but only a few for a short time?

I believe all alternators are negative ground?

Paul

Traditional Farmer · Dec 28, 2015

I have a 1963 Allis Chalmers D19 that's 12 Volt and its positive ground.

Tx Jim · Dec 28, 2015

(quoted from post at 07:56:08 12/28/15)

I believe all alternators are negative ground?

Paul

There are some positive ground alternators.

Case Nutty 1660 · Dec 28, 2015

on CASE all tractors built at the Racine plant were NEG ground,,,, so your 900 would be as well, the Rock Island units were all POS ground
cnt

buickanddeere · Dec 28, 2015

Ah yes. Earth and ground , the same but different . I was bewildered for a while when working on an electrical system in Haiiti. The jack of every trade and manager of maintenance Irish lady and myself were working on a solar battery charging and UPS system. It took some time before I understood that "earth" in a thick Irish accent referred to grounding the system.

Donald in MN · Dec 28, 2015

IH switched to negative earth on the number series when they went to the 12 volt systems the exceptions were the 100 and 200 the last positive earth IH that i remember was a 340 my dad had the letter series diesels were 12 volt but i dont remember which way they were grounded

WGM · Dec 28, 2015

When tractor builders went from generators to alternators is when ground went from positive to negative.

rrlund · Dec 28, 2015

All Olivers with a generator were positive. They went to negative when they went to an alternator.

rusty6 · Dec 28, 2015

One tractor that always confuses me when I go to install the battery is the John Deere AR. So much that I actually looked it up in the manual and then marked the correct hookup with a felt marker on the underside of the battery case lid. Now just working from memory I am going to say it is positive ground and know it is 12 volt.

John T · Dec 28, 2015

1) All two cylinder John Deeres and the early New Generation that still used Generators instead of Alternators used the tractors iron frame as a return current path and were commonly referred to as POSITIVE GROUNDED as the batteries POS connected to the tractors iron frame.

2) Many (not all) early tractors of the 30's through 60's or so vintage that were still 6 volt were POS ground but when they started using 12 volts many (not all) changed to NEG ground.

Of course, that has nothing to do with nor any reference or bond to Mother Earth lol Our electrical grid distribution system, however, has its Grounded Neutral conductor indeed bonded to good old Mother Earth.

I have no literature to show all the brands and if they were POS or NEG Ground and what years and models were such, SO THE ABOVE IS ONLY A GENERAL GARDEN VARIETY ANSWER..............Take or leave it at your own risk and peril.

John T

IanC · Dec 28, 2015

Arrrr-th, or Air-th? Talking on the phone with my relatives can get real interesting sometimes.

Welding man · Dec 28, 2015

Actually they are not, I have a 6 Volt Postive Ground Alternator on my Ford 2000.

Andy Martin · Dec 28, 2015

(quoted from post at 08:42:45 12/28/15) 1) All two cylinder John Deeres and the early New Generation that still used Generators instead of Alternators used the tractors iron frame as a return current path and were commonly referred to as POSITIVE GROUNDED as the batteries POS connected to the tractors iron frame.

2) Many (not all) early tractors of the 30's through 60's or so vintage that were still 6 volt were POS ground but when they started using 12 volts many (not all) changed to NEG ground.

Of course, that has nothing to do with nor any reference or bond to Mother Earth lol Our electrical grid distribution system, however, has its Grounded Neutral conductor indeed bonded to good old Mother Earth.

I have no literature to show all the brands and if they were POS or NEG Ground and what years and models were such, SO THE ABOVE IS ONLY A GENERAL GARDEN VARIETY ANSWER..............Take or leave it at your own risk and peril.

John T

While I always find John T's posts interesting, This one just hit me funny, the acronym used for Positive is the same as Piece of Sheet. 6 volt were P.O.S. ground can sure be taken two ways. LOF

Dell (WA) · Dec 28, 2015

Bill........while there is an obscure advantage to positive (+) ground, negative ground (-) came about because of 12-volt ALTERNATORS. The alternator is an ALTERNATING CURRENT device that needs to be changed to DIRECT CURRENT by 1-way valves called DIODES to charge a BATTERY. The outer case of the diode is NEGATIVE but needs a HEAT SINK to keeper COOL so the silicon doesn't melt. The case of the alternator acts as an HEAT SINK. While you kenn "insulate" the alternator case from the engine block that is generally a non-starter 'cuz its EXPENSIVE. Wanna blow yer mind? Consider the FIBERGLASS CORVETTE. Bottom line, "earth" (or ground) kenn be positive (+) and negative (-) at the same time. Ain't electrons funny???........electrical Dell, FCC 1st Class License and retired Boeing Flt Test Engr

John T · Dec 28, 2015

Hey that makes sense and I never before thought of POS meanings when I was referring to Positive Ground lol

John T

John T · Dec 28, 2015

But remember Billy Bob and Bubba who wired their garage while consuming a case of beer and by golly they are electrical experts so think we can explain positive versus negative ground to them ??? lol

John T Too long retired Electrical Engineer but enjoy our fun and our sparky chat

guido · Dec 31, 2015

Hello Dell (WA),

Chrysler uses both positive and negatine ground diodes. The outer case is ground on both. But I guess you knew that?

Guido.

Positive or negative earth

Member

Well-known Member

Member

Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Well-known Member

Similar threads