power

[ajhill]

I work at a glass plant. pg&e supplies power from a station in los banos, and another in fresno ca. the way the system works is when there is a disruption of power from one then a transfer switch is automatically operareted but there is an power outage that still occurs. My idea is we would install a system that would have both services online at all times and the only thing that happens is the demand on one service would increase when someone hits a power pole again, or some other condition that would interupt the service either from Fresno or Los Banos. I dont think it is cost effective but the plant produces up to 1400 bottles a minute priced anywhere from 2 to 7 dollars a bottle. so what is your knowledge or opinion.

 

[zog]

What you are asking for is a very typical system for manufacturing plants, refered to as a secondary selective substation. Could be simple or very hard depending on what you have in place already. Can you be more specific about your current system? A one line perhaps.

 

[rcwilson]

Paralleling the two utility feeds from different substations is probably not allowed by the utility. There are fast solid state transfer switches that operate at uitlity voltage (13.8 kV for example) that could safely do the transfer faster than a mechanical switch. S&C Electric and other ocmpnaies make them. Check it out on line.

There will still be some voltage disturbance becasue the switch won't transfer until it detects a problem with the incoming voltage. A rotary UPS system might help keep the voltage up enough to prevent loss of production.

But paralleling the two uitlity feeds is probably not possible, unless you put in a lot of switchgear and relaying and pay for a few changes at the utility substations.

 

[stew]

In Seattle there is a long tunnel that connects to our floating bridge over Lake Washington. The power comes in from 2 different sources and mates up in the master control room. There is also a large battery backup there as well. Transfer from one utility to the other is virtually seamless.