What must be done to reset the cryogenics?

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jmc2000
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Joined: Sun May 08, 2011 2:51 pm

What must be done to reset the cryogenics?

Post by jmc2000 » Fri Aug 19, 2011 12:29 am

If there is power cut causing an upset for the cryogenics, what must be done to bring it back onlline when the power returns?

Kasuha
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Re: What must be done to reset the cryogenics?

Post by Kasuha » Fri Aug 19, 2011 9:57 am

If there is any damage to the cryo machinery, repair it or use redundances. Start it all up and wait till all parts that need to be cool are at their nominal temperature.

adam_jeff
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Re: What must be done to reset the cryogenics?

Post by adam_jeff » Fri Aug 19, 2011 11:55 am

Yes, the main delay is in cooling everything back down again. The cooling plants come online fairly quickly after a power cut, but if the cut was for more than a few minutes then the helium inside the cryostats will have started boiling off and the components start to warm up. They need to produce a lot of liquid helium to replace the stuff that boiled off and cool everything down again. That's what takes time.

pjotertje
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Re: What must be done to reset the cryogenics?

Post by pjotertje » Fri Aug 19, 2011 7:25 pm

Problems with sector 45 again

jmc2000
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Re: What must be done to reset the cryogenics?

Post by jmc2000 » Fri Aug 19, 2011 7:42 pm

pjotertje wrote:Problems with sector 45 again
Yes, and I was just about to the ask a question: " Sector 45 is not showing any indication of cooling down right now, yet the LHC dashboard claims the beam will be back tomorrow afternoon - how?"

Kasuha
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Re: What must be done to reset the cryogenics?

Post by Kasuha » Sat Aug 20, 2011 7:48 am

jmc2000 wrote:the LHC dashboard claims the beam will be back tomorrow afternoon - how?"
Keeping these messages up to date is not their primary concern. It's just 'operator chat', important information goes through different channels.

jmc2000
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Re: What must be done to reset the cryogenics?

Post by jmc2000 » Sat Aug 20, 2011 6:42 pm

Kasuha wrote:
jmc2000 wrote:the LHC dashboard claims the beam will be back tomorrow afternoon - how?"
Keeping these messages up to date is not their primary concern. It's just 'operator chat', important information goes through different channels.
Well I can't comment since I don't have direct access to what their policty is over there, nor would I want you to reveal too much about what's going on over there since it's appreciated you giving useful information here.

On the other hand, it wouldn't surprise me that no one saw the sector 45 temperature suddenly shoot up off the cryogenic's operator screen because of a new fault during a period when they were trying to get all the sectors to cool down after a power fail. Which is understandable given the unique circumstances they were under.

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