Re: Explain 3 Phase

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>" <A123X-at-aol-dot-com>

So does that mean that between the hot holes in each set of two outlets there 
is a 240v difference?or is that not the way it works? 


In a message dated 4/27/01 5:18:08 PM Eastern Daylight Time, tesla-at-pupman-dot-com 
writes: 


  One more time.....  The electrical service supplied to 99.9% of American 
>
> homes is single phase, 120/240 volt, 3 wire service.  Single phase means ONE 
> phase...period....not 2 phases 180 degrees apart.  The service enters the 
> house via a cable comprising two insulated (hot or line) conductors wrapped 
> around an uninsulated, grounded, neutral conductor.  The neutral conductor 
> is connected to the midpoint of the secondary winding on the distribution 
> transformer on the pole or the pad and connected solidly to ground.  The 
> voltage between the two line conductors is 240 and between either line and 
> neutral is 120.  The function of the neutral conductor is to carry the 
> unbalanced portion of the load.  If you had only identical 100 watt, 120 
> volt light bulbs as the only loads in your house, and they were evenly 
> distributed so the same number of bulbs ran on each line conductor, the 
> neutral conductor would carry no current.  The two line conductors are of 
> opposite POLARITY compared to the neutral conductors.  The same situation 
> exists on a Y connected 3-phase bank.  The neutral is grounded for safety 
> reasons.  One of which is that the maximum voltage from line to ground in 
> your home is 120 volts.  So, even if you stuck your finger in a 240 volt 
> dryer outlet, you would feel a 120 volt shock, provided you had good contact 
> with the ground.  To experience 240 volts you have to stick both fingers in 
> the outlet.  DON'T TRY THIS!  Hope this helps.  Coil safe!