Date: Tue, 27 Oct 1998 05:44:26 -0700
From: long@apo.nmsu.edu (Dan Long)
Subject: 2.5m obslog 981026
                          MONDAY OCTOBER 26, 1998
                     APACHE POINT OBSERVATORY SDSS 2.5m
                              OBSERVING  LOG
   We were unable to open the enclosure tonight due to clouds and several
periods of rain, and even a couple thunderstorms.
   Even though we didn't open, there were couple events worth noting.  The
first is a repeat of last night's flood of the enclosure.  This time the
water came in faster than I could mop it up, so the lower enclosure got
quite wet.  I still managed to collect over 5 gallons.  I placed a cover
over the rack containing the mirror support system and the camera UPS.
   I think I may have a better idea where the water is coming in.  While it
was pouring in, I managed to follow it back all the way to the top of the
door.  It may be that water is collecting along the top of the door, then
once inside, coming down the beams either side of the door.
   In any case, there was quite a bit of water dripping down beside the
door.  It was getting several junction boxes wet, so I shut the breakers
off to the door, and to the SW receptacle  ( switches 4 and 16 I believe ).
   The evening's second amusement was the imager turning itself off because
the watchdog received  an over-temperature reading from the trailing power
supply.  After checking things like the glycol loop and the case of the
saddle bag, and noticing that the temperature bounced around on the order
of 10 C in a minute ( while the other supply was rock steady at 22 C ), we
turned the camera back on, and about five minutes later shut itself down
again.
   We talked to Connie, and after we described the situation, she concluded
the temperature sensor was dying.  To prevent the watchdog shutting down
the camera every 5 minutes, Connie wrote some forth code to mask that
particular bit.  If the camera is rebooted, the code will have to be
re-loaded.  A message on what to do follows.
if the micro reoboots, which is signaled by the EXEC_BOOT UNACKNOWLEDGED
error, then you will need to telnet directly to the
camera via
telnet t-g-sdss-2.apo.nmsu.edu 3800
and give a
: FIXKA KAFAULT @ 251 AND KAFAULT ! ;
(the complete line)
then exit the telnet session.
after that, doing a
cc fixka
from IOP will clear the watchdog death timer.
   Note that the camera was run this way for over 5 hours during the
remainder of the night while the trailing power supply "temperature
reading" jumped around between 30 and 130 C.
   At about 5:00 I switched 180 liter dewars.  The empty is still in the
enclosure.
                                   Dan