There are several machines at work that have emergency shut off switches in case of an accident, like a centrifuge and an X-ray generator. I always figured they worked just like the normal power-off button, but I’ve been told to avoid using them unless it’s an emergency because it is a pain to get the machines up and running again. Then tonight during a Futurama rerun Leela had to cut off the ship by hitting the “Emergency Shut Off” button (since Fry was using the ship as a hair dryer), and she then said “Fry, do you have any idea how long it will take me to realign the engines” or something like that.
How does this button work, and why would cutting the power to a machine require hours to fix?
I don’t know how those particular ones work, but if it really is an emergency, to cover all the bases you want to de-energise everything, and stop all moving parts immediately. A sudden stop can affect precision stuff, and ruin current operations; if the emergency system uses special measures, resetting them might involve some work for a technician.
I don’t have any specific examples, but I’ve heard that the first hard drives (really really big and heavy things, the size of a table and as heavy as a car) sometimes had claws that would stick out and stop the disks real quick (but with, of course, great injury to your data). I’ve also heard that in some mainframes that button caused the main power cord to be cut with something nonconductive.
Does no-one else there know? Got an instruction manual handy?
EMO (Emergency Manual Off) buttons shut down all of a machine’s critical functions (moving parts, high voltages, over pressure) . Never be afraid of using one in order to prevent loss of life or limb. If you have just entered a wrong command and are worried about the boss finding out, that’s another matter. If there is the remotest chance of injury or harm, shut the d@mn machine down and be sure that a good boss will praise you for being safety conscious.
Any supervisor who would demote you for being concerned about a safety related issue is not one you want to work for. NO PAYCHECK is worth risking one’s life over.
I work for Australia Post. Our mail processing machinery has big red buttons all over. They are of two types. There is a transport stop button, and an emergency stop button. If you need to stick your fingers into the machine to clear a jam, you press the transport stop button. This stops the moving parts, but the machine is still powered up. If a person’s safety is at risk, or the power starts fluctuating (like in last year’s bushfires), or something weird happens like the ceiling starts leaking water onto the machine, then you hit the emergency stop button. This kills the three-phase power to the machine, and the entire machine goes dead. Pushing this unnecessarily will require the machine’s computers to be rebooted. The older machines would take about 45 minutes to come back on-stream. The newer ones take about 15, but that still represents roughly ten thousand fewer letters being sorted, so the employee can expect an arse-kicking.
And what Zenster said. I am the (Homeresque) “Safety Guy” at work, and spend a disproportionate amount of time reassuring people that it is ok to use the emergency stop if you need to, and that if they get an unjustified arse-kicking from the supervisor, I’ll be reporting said supervisor to the appropriate govt. agency.
A lot of 80’s and 90’s disk drives could die if the power was instantly cut also. These drives relied on the motion of the platter to let the head ride on a small cushion of air. During shutdown the head was parked to a safe area on the drive. If you removed the power without parking the head then the head would scrape along the surface of the platter as it spun down.
In cases where there are computers and/or drives set up on the line you will have to reset all of the equipment, the breakers, and the shutdown system in order to get the stuff up and running again. Then you have to reboot the computers the drives and other interlocks and resets. This could involve a handfull of technicians, the electrician and the lead person on the line.
Youre interupting power to the equipment without an orderly shutdown and that throws everything out of whack. Most EPOs have the electric cut instantly, others have other things like water and pnuematics and gas cut also.
Editor: [reading Homer’s restaurant review] Not bad, not bad at all! We’re going to run this on page one … of section H-2.
Homer: Whoo-hoo! Stop the presses!
[Man hits stop button, wrecking havoc in the plant]
Homer: OK, Start the presses.
Editor: That takes four hours!
Homer: Whatever, I’ll be at Moe’s.
When pressing the emergency stop in some meatal machining processes, you can almost count on turning the part you’re working into scrap, ruining the tools or inserts, and possibly misaligning the jig holding the part in place.
So it could take considerable time to recover.
BUT as stated, do not hesitate to use it if you feel you’re in danger.
Some of the electronic equipment I work with is liquid cooled, and when you hit the Emergency button, everything is shut down, including the coolant flow. In such cases, some stuff will just melt. After a big shutdown, we have to send everything back to get tested and recalibrated, which eats up a lot of time and money. However, the culture in my company is such that I don’t remember anyone (in 19 years) receiving flak for hitting one of the (big, red, fist-sized) buttons.