Re: power-grid physics

[Rick Tarara <rtarara@SAINTMARYS.EDU>]

Having had a short power outage in our home area on Saturday and knowing
that some customers were back up within minutes while we were down 3 hours,
I think that John is correct that there are multiple switches at the load
end.  I don't know if these are at substations or even on area transformers
(some evidence of the latter) but such would explain why it takes a while to
get everyone back up.  I'm envisioning that the service people have to drive
around the effected area and reset switches.

Rick

----- Original Message -----
From: "John S. Denker" <jsd@AV8N.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Wednesday, August 20, 2003 3:17 PM
Subject: Re: power-grid physics


> On 08/20/2003 03:37 PM, Rick Tarara wrote:
>  >
>  > Power is off. Two generating plants, each with a max output of 1000
>  > Watts--generators at 100 Volts. One transmission line at 1000 volts.
>  > A load (still switched on) of 1600 Watts--say two factories each
>  > wanting 800 Watts at 100 volts.
>
> Interesting scenario.
>
>  > OK--how do you turn the power back on?
>
> You'd better hope that there is a switch in
> the circuit diagram between the two factories, so
> that they can be brought up separately.  If not,
> this is a deadlock scenario:  if the power goes
> out it will never come back on.