Dome Encoder Issues, Fugue State?

Sunday, March 29, 2015 1:22 PM

Problem(s) Encountered:

Had trouble with the dome encoders getting lost multiple times throughout the night, requiring manual reset. See trouble report for details.


Solutions:

Per John Thostensen:

The problem sounded a bit like an intermittent issue we''ve had, which I dubbed the "fugue state*" in which the dome starts to rotate slowly for no reason until it finally decides not to at some random point.  There''s no way  to clear it; one just keeps observing using this procedure:


- disable the yellow button at the bottom of the left computer rack - this gives manual control of the dome.


- read the telescope azimuth on the TCS (or the repeat monitor in the dome)


- In the dome, use the rotation control to manually set the dome to the correct azimuth; match the red reflective tape at the bottom of the dome shutter opening to the red reflective strips every 10 degrees around the dome


- continue to observe.


- After about a half-hour, try re-enabling the dome; if it takes off, wait some more.