Thursday, April 19, 2012

Only Two Thermocouples Remaining to Measure Reactor 2 Pressure Vessel Temperature?

TEPCO's "Status of TEPCO's Nuclear Power Stations after the Tohoku-Chihou-Taiheiyou-Oki Earthquake (Daily Report as of 3:00 pm, April 19)" states:

On April 18, we evaluated the reliability of the thermometer (RPV bottom head 135°) which was monitored for reference based on safety regulations 138 through direct current resistive measurement. We evaluated the thermometer broken down based on the increase in direct current resistance. No large swings confirmed at other thermometers, monitoring posts, and PCV gas management system indicators. We will continue monitoring PCV temperature by thermometers (RPV bottom upper head 270° and RPV upper skirt junction 135°)

The failure of the thermocouple "69H2" (at RPV bottom head at 135 degrees) was noted in the blog post on April 15. So now there are two thermocouples left on the RPV of Reactor 2 - 69H3 and 69F2 - to measure temperatures to make sure the reactor is in the "cold shutdown state".

(Pay attention to the word "state", which makes this "cold shutdown" uniquely Japanese.)


Hélios said...

Hello Ultraman,

OT, an article in Enenews about pollen in California, Arnie Gundersen :

Thank you for your work. I follow you every day and translate on my blog.

Chibaguy said...

Here is my insight from living here over a decade; the NRC and IAEA et al are fuming. Thank you NISA/TEPCO for exposing the nuclear industry! No one that can critically think will ever say Fukushima is under control for decades. Penetrating the Japanese culture is even beyond the IAEA.

Anonymous said...

This may very well be a dumb question, but here it goes anyway:
If there is such trouble with the thermocouples in reactor 2 AND reactor 2 is the least problematic one, then how does TEPCO figure that reactors 1 and 3 are also in the socalled "cold shutdown state"? (Agree with elbows that the term is abused in describing the Fukushima situation, but just to stick with their terminology.) I mean, any temperature measuring "thingies" working in those reactors?

elbows said...

Reactor two is only the least problematic one in the sense that the building didn't explode, and the contamination at various useful places within the reactor building isn't very high. In many other ways its just as problematic as the other reactors, and in some ways perhaps more problematic. In terms of temperature measurements that, at a minimum cause bad PR its certainly been the most problematic this year.

Anonymous said...

Thank you, elbows.
But given there were explosions in the other reactor buildings AND the radiation is higher, how can TEPCO (or can they?) ascertain that the thermocouples in those are working correctly? Or how else can they claim the "cold shutdown state" of reactors 1 and 3?

Atomfritz said...

I just guess they'll refrain from the cooling adjustment they tried at #2 that went so bad, causing so many thermocouples to "fail" for some mysterious reason.

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