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Cram Switch: [from The Nuclear Power Industry] N. An Emergency-power-off Switch (see {Big Red Switch}), Esp.

:scram switch: [from the nuclear power industry] n. An
emergency-power-off switch (see {Big Red Switch}), esp. one
positioned to be easily hit by evacuating personnel. In general,
this is *not* something you {frob} lightly; these often
initiate expensive events (such as Halon dumps) and are installed
in a {dinosaur pen} for use in case of electrical fire or in
case some luckless {field servoid} should put 120 volts across
himself while {Easter egging}. (See also {molly-guard},
{TMRC}.)
-- The AI Hackers Dictionary

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