Press conference live link is here.
Reactor 2 RPV's thermocouple that's been going up seems to have finally broken. (0r else...)
15:00 285.4 degrees Celsius
Screen capture from the press conference screen:
The last time this particular thermocouple went to that level, it was March 2011.
TEPCO was measuring the electrical resistance of the thermocouple before the temperature suddenly shot up to 285 degrees at 3PM.
Resistance 500 to 530 ohm.
The instrument has totally failed, says TEPCO's Matsumoto.
Interesting question from a reporter from Nico Nico: Are you going to test the other two thermocouples at the bottom of the RPV?
Yomiuri: Did measuring the resistance break the thermocouple?
A: We don't know why the temperature shot up after we finished the measurement.
Yomiuri: Do you know when this thermocouple broke?
A: At least, until the end of January it was showing the same trend as the other two. We want to carefully compare with other thermocouples.
Jiji Tsushin says right before 3PM, the temperature was 342.2 degrees Celsius.
Q: Who decided that the thermocouple was broken? Was the manufacturer consulted?
A: TEPCO decided. We have experience in maintenance of the thermocouple. (Matsumoto sounds very testy.)
Q: Is there a possibility of a thermocouple showing temperature lower than what really is and therefore it is broken?
A: If this thermocouple were correct, there would be other thermocouples that would show higher temperature. The other temperatures are trending down. So we think this particular thermocouple is broken.
Q: The temperature rise in early February - was it related to the instrument failure now?
A: We think so. But we didn't know at that time whether it was actually a rise in temperature or the instrument failure. The temperature did go down after increasing the water injection.
Q: How reliable is it to judge "recriticality" by xenon-135?
A: We think it is a reliable indicator.
Q: When was 342.2 degrees Celsius recorded?
A: We finished the testing at 2:54PM. So it must be between that time and 3PM. We'll have to check.
Q: How high did the temperature go? (looking at the graph that was provided)
A: It went overscale, so the graph shows temperatures like that [over 400 degrees Celsius].