Never push the Big Red Button (New York City subway failure)
Sean Donelan
sean at donelan.com
Fri Sep 17 13:59:28 UTC 2021
Sigh, people often mis-hear this when I say it, so I will try to say it
carefully.
If you have an Emergency Power Off (EPO), the electrical code (and
life-safety code) allows use of several alternative wiring methods. Some
people mistakenly believe the allowed alternatives are the rule, but they
are actually exceptions.
On the other hand....
If you do NOT have an Emergency Power Off (EPO), you are NOT allowed to
use the associated alternatives in the electrical code. Among the
alternatives NOT allowed without the EPO, is almost everything in
Article 645 - Information Technology Equipment rooms (or the equivalent
in international electrical codes). Most people, including licensed
electricians, believe it is the other way around.
Why does Article 645 exist? (and equivalents in other international
electrical codes)
IBM in the 1950s published construction specifications for Automatic Data
Processing rooms for its mainframe computers, which everyone else copied.
IBM wanted to use alternative wiring methods in ADP rooms for its
mainframe computers, so the Big Red Button was born. Also, mainframe
computers used to cost more than the building, so people (insurance
companies) didn't want the mainframe damaged during a fire.
It is possible to design a data center WITHOUT using those electrical
code exceptions, and WITHOUT a "Big Red Button."
You can check, because my data center ideas were copied by several
tech companies world-wide (you know who you are), and don't have Big Red
Buttons. All of those data centers also have water-based automatic fire
sprinklers. Both were very radical ideas at the time, which are now
commonly accepted.
In most cases, you'll need a fully licensed, Professional Engineer
specializing in Electrical Engineering to sign off on the final design.
A licensed electrician isn't enough. Nevertheless, it is possible to
build a safe, code-compliant data center WITHOUT a Big Red Button. The
design also seemed to be more reliable.
Let the misinterpretation begin ...
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