Date: Fri, 30 Jul 1999 23:16:30 -0600 (MDT)
From: Ellyne Kinney
Subject: 2.5m obslog 990730 ( MJD 51391 )
                          FRIDAY JULY 30, 1999
                     APACHE POINT OBSERVATORY SDSS 2.5m
                              OBSERVING  LOG
	Observers:	Ellyne Kinney		(APO)
			Dan Long		(APO)
                        Stephanie Snedden       (APO)
The weather was clear at the beginning of the night, so we planned to get
a pointing model.  As we opened were rolling the building off the
telescope, the building suddenly stopped moving about 2 feet from the east
stops.  The panel on the Rolling Enclosure Drive Cabinet was reading the
error code OH.  We called French and he advised us to open up the cabinet
and look for the manual to look up the error code.  The manual was
missing.
PLEASE!  Whoever borrowed the manual for the Rolling Enclosure Drive
please return it to the inside of the Cabinet.  We need this document for
troubleshooting.  Thanks.
French remembered that OH stood for Overheat, and suggested we try power
cycling the drive.  We had no luck with the first attempt.  French
suggested waiting to let the motors cool down.  We waited ~15 min and
power cycled again, no luck.  We waited a few more minutes, no luck.  Then
Dan open the cabinet and reset the 4 breakers.  We're not sure if this was
what fixed the problem, or if the motor had just cooled down enough, but
the fourth time we power cycled the drives, The error code cleared and we
were able to move the building.
We were able to set the fiducials with a little bit of fiddling.  The Alt
fiducial was registering, but giving the wrong elevation reading at first,
so the first time we set the fiducials it set the altitude to 28 degrees
when we were near 15 degrees.  We reset the Alt back to ~15 degrees and
re crossed the fiducial and this time to worked.  The Az fiducial was set
without problems.  The Rotator was initially off by -10 degrees, so we
could not get a valid fiducial crossing at first.  We had to set the
rotator by hand to ~0 degrees and then we were able to get valid fiducial
readings.
We homed and relaxed the primary and secondary mirrors, and then tried a
track command in the TCC.  It seemed to work at first.  We had motion in
all three axes, but then all three axes died.  We got the error message
Bad Data: ERR: semMEIUPD.  We tried and axis stop ant the rotator ran
away.  When we tried to use the Menu again the MCP had died.  We needed a
hard reboot to bring it back to life.
We stowed the telescope at this point and then call Charlie, to let him
know the status.  Debugging and testing will continue tomorrow....
Ellyne