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Fri Apr 4 16:54:06 2008
Weather station is fully alive
After today's trip to the roof of our building the weather station seems to be completely resurrected!
We went to the roof together with Steve Vass, and we discovered that:
(1) Sensors of wind speed, wind direction and the bowl that measures the amount of precipitation do not have any visible defects, so there is no problem with all those sensors even after being outside for seven years.
(2) We discovered that there are cable junctions located on the roof, and those junctions were located close to the rim (edge) of the roof, before the cables go inside of 40-meter lab room. The taping in the place of the junction was not good due to the age, and
the connections between the cables were disrupted
(cable endings were out of the connectors). Therefore, no signal from the roof sensors could be transferred to the 'Weather Monitor'. It was not wise from the person who installed the weather station to leave the fragile cable connections outside, on the roof, because the length of the cables allowed to locate those three connectors inside of the building.
See the attached PDF-file with pictures.
(3) After the cables were plugged into the connectors, these cable junctions were gently pulled into the inside of the 40-meter interferometer room.
These cable junctions should not be located outside of the building!
Immediately after all the above-mentioned steps, the reasonable indications of outside temperature, humidity, pressure, wind speed and direction appeared on the 'Weather Monitor'.
In order to see if there is any problem of communication between the 'Weather Monitor' and UNIX control computers through 'c1pem1', I rolled out two brand new black cat-5 ethernet cables on the floor of the interferometer room (they are on the floor temporarily, the ethernet cable will go from the floor into the ceiling cable tray eventually), connected the two cables together through freshly purchased from Caltech bookstore cable connectors, and thus connected the 'Weather Monitor' to the processor 'c1pem1'.
Now we can see reasonable indications of outside temperature, pressure, amount of precipitation, wind speed and direction on the EPICS screen! Moreover, these indications are changing with time.
As a reminder for everyone: standard atmospheric pressure is about 101kPa, so the indications of pressure as 99900Pa is quite reasonable.
One thing is not clear for me yet: wind speed on the 'Weather Monitor' is fluctuating between 2 and 4 mph, while MEDM EPICS-screen values are fluctuation in the range between 0 and 3mph.
Many thanks to Steve Vass and Alexander Ivanov for their help.