Rule 1: In bad weather, close the Robodome before shutting down the software.

This is the quickest way to protect RoboDIMM from humidity or precipitation.  The software takes longer to
shut down and there are no serious consequences from having RoboDIMM running inside a closed dome.
However, as soon as you can, shut down the software using "stoprobot".


Rule 2: Close the Robo-dome when there is RH>75% at any of the ING telescopes.


Marco's statistics show that if humidity reaches 75%, it is most likely to soon rise to >90% (correct me if I'm wrong, Marco).
At present there is no %RH measurement at RoboDIMM, so this policy is the best way to ensure that the equipment is not exposed to
high humidity. Another advantage of this policy is that Robodome will already be safely closed when it comes
time to decide whether to close the WHT dome.

Snow and/or Ice

Rule 3: If you are at the telescopes when snowy or icy weather begins, day or night, please follow the same procedure
as detailed for "Lightning" below.

Reasoning :

Following ice or heavy snowfall, it may become impossible to open the Robodome for several days. Therefore, as soon as this
kind of weather appears, RoboDIMM needs to be prepared for a long term shutdown. It is preferable to individually power down
delicate items of RoboDIMM hardware, in case there is an electrical storm during this time. However, we recomment leaving the dehumidifier switched on because this keeps %RH inside the Robodome below 75%.

Additional comment:

In conditions of high humidity, low temperatures and wind, ice coverage can become quite severe, covering not only the dome opening
but also encasing the dome motors in ice. After such an episode, the ice should be allowed to fully melt before attempting to open the Robodome. Someone must inspect it during daytime, preferably RoboDIMM Project Manager, Carlos Martin. It must never be assumed that the Robo-dome is free of ice just because it becomes safe to open the WHT dome, following an ice episode.


The telescope shakes a lot even in moderate wind, resulting in the star image not appearing completely inside
the CCD sub-window during a seeing measurement series.  This is easily observed on the new GUI display.
Besides making it (near) impossible to measure seeing, this amount of movement may be damaging to the
telescope drive mechanisms.

Therefore we recommend closing the RoboDOME if Wind speed or Gust read > 35 kph on either the WHT or
JKT mast readings.  You may also close if you observe so much image motion that seeing is not being

Carlos is currently working on improving the isolation of vibrations in the central "Serrurier" tower, coming from
the access platform, by changing the humidity-sealant material between the two.


Rule 4: If the WHT has to stop observing because of cloud, definitely close the Robodome. It is much more important
to protect RoboDIMM from rain than to take data through cloud. Note that RoboDIMM may have no problems
observing even when cloud is too thick for the observing program at the WHT.

We plan to install a rain alarm next spring.


Rule 5: if an electrical storm is observed anywhere in the sky, even if this is currently on the horizon and the WHT
can still observe (as can happen), we recommend that delicate systems be powered down, using the procedure
detailed below.


Electrical storms are particularly dangerous because RoboDIMM is a possible lightning conductor. The cables
that link it to the WHT building have lightning protection built in, but RoboDIMM itself is still vulnerable.  Since such storms are
usually accompanied or shortly followed by wet weather, RoboDIMM should in fact be prepared for a long term shutdown.
This procedure is designed to safely shut down the RoboDIMM hardware prior to a possible decision
to shut off RoboDIMM power at source, to be taken by the Incident Officer.

Procedure for long term shutdown: