Why is Electrical Switchgear Important to Critical Facilities?
(A Non-Technical Explanation)
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| Nick Cage on top of one of the largest critical telco buildings in the world in the movie "City of Angels" |
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| Street-Level View of 420 S. Grand (part of The Madison Complex) |
The Basics:
Electricity ALWAYS seeks the path of least resistance on its way to Ground. By ground, we literally mean the earth that we walk on. It's just one of many physical facts. For example, a lightning bolt will always bypass insulation to try to find conductive metals (or non-pure water or a golfer...) on its way to where it is going.
A Short-Circuit
An electrical short aka "Short Circuit" is a technical term that describes a condition in which the electrical current is provided a short-cut to ground. For example, if we were to place a piece of metal wire between the terminals of a small (e.g. 9 Volt) battery; that condition would be considered a "short". This is simply because the current induced by this battery is meant to flow through the circuit of the device we are trying to provide power to - NOT to go directly from one terminal to the other (the short).
Switchgear
In general, there are two basic conditions that need to be mitigated: 1) Too Much electrical current (or power) and 2) Too Little electrical current (or power). Have you ever witnessed the lightbulbs in your bathroom flicker when using a hair dryer? This is because your hair dryer is drawing a greater amount of current from your electrical circuits that other devices. Switchgear; or more precisely; the circuit-breakers (the GFCI outlet in your bathroom is a tiny circuit-breaker) mounted inside a switchgear panel, regulate the amount of current drawn into what is called a "branch-circuit". (see the Single-Line drawing below)
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| Example Single-Line Diagram (ATS Interlock in Green & Generator in Orange) |
In the above Single-Line diagram, the backward-looking "C"s are symbols for each circuit-breaker.
Critical Facility Power Outages, the ATS, and the Generator
In the event of a loss of Commercial Power (COMM'L SERV depicted top-center of diagram), the integrated and interlocked ATS or Automatic Transfer Switch (interlock highlighted in Green) senses a loss of power, "disconnects" from the commercial power, and "connects to" the Stand-by Generator (highlighted in Orange). While the Generator ramps up to speed, the data center batteries discharge power to the critical circuits (those mandated per code & company regulation: Fire/Life/Safety, etc). Once the Generator is ready, the critical circuits are transferred until Commercial Power is back on-line.
Why should Nicolas Cage Care?
Well, if he were dumb enough to stand on top of the antennas again during an LA thunder storm, he might care that these critical facilities are carefully engineered by one entire company group responsible for ensuring that ALL electrical currents go where they need to go (and nowhere else). [But, I still wouldn't recommend anyone stand near those antennas - for many other reasons]
