OUR VIDEOS GALLERY MEMBER SPONSORSHIP VENDOR SPONSORSHIP

User Tag List

Results 1 to 7 of 7

Thread: Negative Earth V Positive Earth

  1. #1
    Expert
    Join Date
    Aug 2011
    Location
    River Heads Q
    Posts
    445
    Thanks
    196
    Thanked 342 Times in 137 Posts
    Mentioned
    4 Post(s)
    Tagged
    0 Thread(s)

    Negative Earth V Positive Earth

    This will probably open a can of worms.
    We had a very experienced (older) maintenance bloke come over to the Island to fix our generator and he commented on how much rust was evident on the outside. It sits out in the weather and considering lack of proper maintenance it receives, the 23,000 + hours running time is amazing.
    He also commented that the old American cars that were positively earthed did not rust as much as negatively earthed vehicles from the rest of the world. How is this so? There must be a scientific answer for steel and electricity to make rust. I wish I studied chemistry at high school instead of just attending class.
    If this is true, I can understand why they changed to negative earth because if a car did not rust away, they would not sell more new cars
    At the end of the day, all you have is yourself and all you need is your friends (and in our case our Patrol)
    2006 GUI1 4.2TDi Coil Cab "almost" standard

  2. The Following User Says Thank You to Wizard52 For This Useful Post:

    MB (23rd February 2021)

  3. # ADS
    Circuit advertisement
    Join Date
    Always
    Location
    Advertising world
    Posts
    Many

     

  4. #2
    Advanced Truckus's Avatar
    Join Date
    Feb 2021
    Location
    Central Coast NSW
    Posts
    59
    Thanks
    12
    Thanked 54 Times in 26 Posts
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Interesting considering cathodes and anodes used on ships hulls for corrosion prevention, normally the anode (positive charge) would erode instead of the cathode (hull), so if anything positive earth or in vehicles case positive ground points would likely encourage corrosion in the copper wire, same principle as cathodic protection..anyhow, too many beers and dead brain cells ago to debate so have a read here

    https://mgaguru.com/mgtech/electric/et098.htm

    and draw your own conclusions.
    2005 Y61 GU rebuilt 2020. 6.5 L turbo inter-cooled Diesel, SupENG Superflex 4 Inch Lift Kit 2,0 Remote res Fox shocks, offset trunions, 315/75/16 Maxxis Razr, 16 x 12 steels rims, SupENG drop box, Stedi Spots & bars, 12000 lbs winch,rear locking bars with duel tire carriers, 4 XtremeENG S/S snorkel, rock sliders, SME UHF, ARB Hard mount Air compressor, ARB fwd & rear air lockers,Rhino roof racks, Duel battery set up, 12 V dist swbd ,

  5. The Following User Says Thank You to Truckus For This Useful Post:

    MB (23rd February 2021)

  6. #3
    ......... MB's Avatar
    Join Date
    Nov 2015
    Location
    Yarra Valley
    Posts
    6,434
    Thanks
    16,286
    Thanked 7,738 Times in 3,594 Posts
    Mentioned
    361 Post(s)
    Tagged
    0 Thread(s)
    Selfishly, this is a cool thread to read/learn hopefully answering my questions too Legends
    Some 25+ years ago I was given a task from the boss then (hard yakka Irish mentor :-)
    Ran his DitchWitch dead straight under contract required along the Maribyrnong City River perpendicular to Melbourne’s west gate bridge.
    Sucks when we don’t get to fully backfill and complete a job but was slip/told it was an anodey/cathodey thingy going in to protect some serious infrastructure underground & above


    Sent from my iPhone using Tapatalk

  7. The Following User Says Thank You to MB For This Useful Post:

    mudnut (23rd February 2021)

  8. #4
    Expert Brissieboy's Avatar
    Join Date
    Jul 2015
    Location
    Brisbane, Qld
    Posts
    214
    Thanks
    62
    Thanked 197 Times in 114 Posts
    Mentioned
    8 Post(s)
    Tagged
    0 Thread(s)
    Telephone exchanges used 50v with positive earth to avoid problems with electrolysis. The positive earth system means that the ground side of things is the side that gets depleted (the anode) which matters when dealing with things like the very fine wire of the relays and electromagnets etc which were the basis of the old telephone 'step-by-step' technology. This started with the poms who probably had a much bigger problem with moisture (based on their climate) which is a key ingredient for electrolysis - if it is kept dry then there is little issue either way.

  9. The Following User Says Thank You to Brissieboy For This Useful Post:

    MB (24th February 2021)

  10. #5
    Expert pollenface's Avatar
    Join Date
    Nov 2019
    Location
    Perth
    Posts
    154
    Thanks
    16
    Thanked 66 Times in 47 Posts
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Are land rovers still positively earthed?
    2008 CRD Wagon, 192,000kms and counting....

  11. The Following User Says Thank You to pollenface For This Useful Post:

    MB (25th February 2021)

  12. #6
    Patrol Freak
    FNQGU's Avatar
    Join Date
    Jun 2013
    Location
    Cairns, Queensland
    Posts
    1,295
    Thanks
    840
    Thanked 1,550 Times in 567 Posts
    Mentioned
    21 Post(s)
    Tagged
    0 Thread(s)
    No expert at all but the major oil pipelines I've been on all have 'cathodic' protection sites situated regularly along the main lines. I was told this was to help prevent corrosion of the pipeline.

    Not my field of expertise though. Where's @Cuppa?
    Had a beaut GU with 6.5 Chev TD, but sold the soul and now driving a 79 series dual cab. Yes, a Tojo on the Patrol Forum! Also having fun trying to build the ultimate Expedition Grade storage box.
    www.openskytouring.com

  13. The Following User Says Thank You to FNQGU For This Useful Post:

    MB (25th February 2021)

  14. #7
    Travelling Podologist Cuppa's Avatar
    Join Date
    Jan 2011
    Location
    Ballarat, Vic
    Posts
    6,398
    Thanks
    1,847
    Thanked 6,628 Times in 2,765 Posts
    Mentioned
    149 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by FNQGU View Post
    No expert at all but the major oil pipelines I've been on all have 'cathodic' protection sites situated regularly along the main lines. I was told this was to help prevent corrosion of the pipeline.

    Not my field of expertise though. Where's @Cuppa?
    A little birdie tells me you know exactly where I am! Hope you had an enjoyable time out west. I actually went looking on the ‘net for the answer to this question about why cars changed to negative earth. In a nutshell I could find no agreement, only several different reasons repeated many times.
    The cathodic protection thing which I reckon is a bit suss, something to do with a change to alternators with internal diode control which sounded possible even though I didn’t fully understand it, ��, and also suggestions that it was somehow cheaper for the manufacturers... which I also didn’t quite get. Another possibility was the introduction of radios into cars - perhaps anyone who knows a thing or two about radios might comment?
    Last edited by Cuppa; 26th February 2021 at 09:01 AM.

    2006 4.2TDi ex-Telstra Remote area Camper. 425w roof mounted solar, 360Ah Aux batts, BCDC1240, Onboard hot & cold pressurised & filtered water, (25 litre hot water calorifier), ARB fridge, ARB freezer, Built in kitchen, heaps of easy access storage, 240v, 3 Genie exhaust + dynotune, 2 lift, Lovells GVM upgrade, second glovebox, ROH Blaktrak steel wheels, Bridgestone D697's (now Toyo RT's), Redarc gauges/pillarpod, Hema HX-1, Icom 450 CB, dual rear view cameras, Onboard 30amp Victron mains charger, second glovebox, dual seat conversion, Tyredog TPMS, Boss PX7 onboard air with 9 litre tank, 350w inverter, Steel bullbar, Harrop Eaton diff lock (front), Warn winch, Snorkel, Dual spares , 160 litre water tank, 180 litre fuel in two tanks (approx 1200km range) 2010 Tvan Tanami. (incl another 70 litre water tank) with matching wheels/tyres (& 3rd spare)
    A Nomadic Life The Big Trip Blog

  15. The Following 2 Users Say Thank You to Cuppa For This Useful Post:

    FNQGU (26th February 2021), MB (26th February 2021)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •