Yesterday's Tractor Co.
Shop Now View Cart
   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
Classified Ads
Photo Ads
Tractor Parts

Discussion Forums
Project Journals
Tractor Town
Your Stories
Show & Pull Guide
Events Calendar
Hauling Schedule

Tractor Photos
Implement Photos
Vintage Photos
Help Identify
Parts & Pieces
Stuck & Troubled
Vintage Ads
Community Album
Photo Ad Archives

Research & Info
Tractor Registry
Tip of the Day
Safety Cartoons
Tractor Values
Serial Numbers
Tune-Up Guide
Paint Codes
List Prices
Production Nbrs
Tune-Up Specs
Torque Values
3-Point Specs

Tractor Games
Just For Kids
Virtual Show
Museum Guide
Memorial Page
Feedback Form

Yesterday's Tractors Facebook Page

Related Sites
Tractor Shed
Ford 8N/9N Club
Today's Tractors
Garden Tractors
Classic Trucks
Kountry Life
Tool Talk Discussion Forum

Re: Basic AC Power Systems

[Show Entire Topic]  

Welcome Guest, Log in or Register
Author  [Modern View]

04-23-2013 16:45:06

Report to Moderator

When you talk about some of these ungrounded systems, you use the terms float and floating. I have heard that before and cannot wrap my mind around what it means. John T or others can you explain it to a neophyte?

Thanks, Garry

[Log in to Reply]   [No Email]
John T

04-24-2013 04:25:00

Report to Moderator
 Re: Basic AC Power Systems in reply to GarryinNC, 04-23-2013 16:45:06  
Can do, A Float or Floating AC power distribution method system simply means ITS NOT GROUNDED. By the way GREAT QUESTION

For example, in your household 120/240 Volt Single Phase Three Wire system that uses just one transformer (perhaps say 7200 or 9600 etc VAC down to 240 VAC) the center of that transformer is tapped, serves as the Neutral, and that point is tied to a #4 Bare Coper Wire that leads down the pole to MOTHER EARTH GROUND. Its a Grounded NOT floating system. Likewise at the main service entrance the Neutral is again tied to a Grounding Electrode via the GroundING Electrode Conductor # 4 bare copper wire.

LIKEWISE In a typical say 208 Y 120 Volt Three Phase Four Wire commercial system, the common tie point where each of the three transformers are all joined together, ALSO SERVES AS NEUTRAL AND IS ALSO TIED TO MOTHER EARTH GROUND (perhaps via a driven into the earth rod or rods or perhaps other suitable Grounding Electrodes), A GROUNDED (NOT Floating) System.

HOWEVER and as used a lot in the thirties through 60's, if three transformers are connected in a Delta configuration (usually 240 or 480 line to line) and theres no connection to earth ground (or any Grounding Electrodes), THEN THAT SYSTEM IS FLOATING. NOTE Im talkin a 240 or 480 Three Phase THREEEEEEEEEEEE Wire here, not 3 phase FOUR wire where (Red/High Leg system) one transformer is center tapped and that point is tied to a grounding electerode.

So in theory if you ignored capacitive and inductive coupling you can be standing barefooted on the ground and touch any lead and not receive a shock since there shouldnt be any voltage with respect to mother earth ground in a floating system. Similar in a plant if one leg got shorted out to a machine or building steel or conduit etc the motor keeps running THATS A FLOATING SYSTEM

That help?? that what you were looking for??

Again GREAT QUESTIONS YALL Hope I helped and didnt confuse by use of my technical jargon, but thats sort of inbred after Purdue and 40 + years lol

John T

[Log in to Reply]  [No Email]
Dusty MI

04-24-2013 06:53:24

Report to Moderator
 Re: Basic AC Power Systems in reply to John T, 04-24-2013 04:25:00  
Quoting Removed, click Modern View to see

I got nailed once on one of those systems once where one leg had unintentionally gone to ground. That hurt worse than 277.


[Log in to Reply]  [No Email]
John T

04-24-2013 08:40:34

Report to Moderator
 Re: Basic AC Power Systems in reply to Dusty MI, 04-24-2013 06:53:24  
Yep, after one leg gets unintentionally grounded (machine or conduit or steel etc) on a Floating Delta, then there exists Line to Line Voltage from the 2 other Legs to conduit or machinery frame or building steel etc OUCH THAT CAN KILL YOU DEAD

John T

[Log in to Reply]  [No Email]
[Show Entire Topic]     [Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:

Fast Shipping!  Most of our stocked parts ship within 24 hours (M-Th). Expedited shipping available, just call! Most prices for parts and manuals are below our competitors. Compare our super low shipping rates! We have the parts you need to repair your tractor. We are a company you can trust and have generous return policies. Shop Online Today or call our friendly sales staff toll free (800) 853-2651. [ About Us ]

Home  |  Forums

Copyright © 1997-2016 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters