[Astro-mdm-trouble] MDM Trouble Report for 2020 Feb 19

[obs13m at mdm.kpno.noao.edu]

MDM Trouble Report for 2020 Feb 19

Telescope: 1.3m
Observer(s): Yuming Fu (PKU)
Instrument: CCDS

Problem(s) Encountered:
Main Trouble: Failed to home telescope in the morning

The observation went well, except that I got slew error every now and then 
(while switching to a new target a bit eastward (within 2 hr in RA)). 
This error was also accompanied by message in the TCS panel: 
Send failed for command track: Network operation timed out. 
And sometimes the tracking got off. I re-enable the tracking and redo the 
slew telescope several times and things were solved. 

In the morning, I first pointed the telescope westwards the zenith to get 
sky flat and everything was fine. Then I turned off the tracking and 
followed the the shutdown checklist to bring the telescope to zenith with 
command [point ha=0 dec=31:57:12 nodome], but got error saying 
[point not converging]. So I tried to use home button to home the 
telescope’s ha axis but still got error “ERROR where m_ha not homed”. 
As it was getting bright outside, I closed the mirror but could not get 
dome homed and closed due to the error. After some unsuccessful tryings, 
I used “home force ha” at last and got avoid of the error temporarily. 
At this point, I managed to close the dome. I wanted to use offset command 
to bring the telescope back to zenith and zero the pointing but ended up 
with a mistake which was to offset ra=3600. That was how things became worse…

At last Eric came and fixed the problem. His comment on the error messages:
When you get timeout errors, or “point not converging” errors, simply try 
issuing the command again.  But make sure that tracking is running—if you 
try to point using an ra coordinate (or JSkyCalc) when tracking is off, 
it will give you an error.

I admit that the “point not converging” error got me in a panic. If anyone
also encounter this problem, first try issuing the command again, just as
Eric had suggested. If you're on the remote mode, it might be better to get
help from the local staffs when you have trouble closing the dome.

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Submitted on 2020 Feb 21 [7:06:00]

Observer Contact Email: fuym at pku.edu.cn
(Note: thiswill not appear in versions of the trouble report archived online)