Use of DIMMs during Stand-down 8
Running the DIMMs during a Stand-down
ING seeing measurements should continue during the WEAVE stand-downs, as they are useful in real time to INT observers (and others) and will later be used for site studies.
- Once started, the DIMMs can, in many cases, be allowed to run after the OSA has gone to bed, as long as the dome is programmed to close at a reasonable time.
- The new DIMM R2D2 will safely stop after the DIMM dome has closed.
- Dome can be programmed to close on the DIMM dome GUI (available on the PC "plcgui") by entering hour and minute in separate boxes labelled "Parameter input" and pressing Enter for each. The registered time is then displayed on the right.
- RoboDIMM should not be run without supervision as it is unreliable.
A reasonable time to close the dome will depend on the OSA's bed time, on weather and on pointing.
- If weather and pointing are good, it seems safe to run the DIMMs unsupervised for say 3 or 4 hours.
- If there are high clouds, it would be best to close the dome when leaving the WHT, to avoid both the risk of rain and of RoboDIMM losing pointing.
- If humidity rises, the dome will close automatically anyway.
- In windy weather, the usual safety guidance should be followed.
- If pointing is not good (particularly if the new DIMM takes an hour to find an object), it would be best to limit unsupervised time to 1 hour.
- The new DIMM will be shut down only if the dimmWatch script is running on taurus.
Check for this on taurus using ps -ef |grep dimmWatch. If the result is only one line (the same grep process) you need to restart the script.
- Restart the script as user whtobs by entering runDIMMwatch&
If the script is not running, the telescope will safely stop anyway but the PC will crash. If not contactable next day, it needs a power cycle.
- RoboDIMM stop time is entered in the RoboDIMM GUI (./ru& to run it).
- Configuration (Simple mode) -> time tab -> enter value in end (hh:mm) and press Enter.
- If you cannot see Enter button you can safely use Tab key to get there and press Enter.
- Note that local time is used both by RoboDIMM and the Dome PLC.
- Software for both DIMMs is recommended to be restarted before running them the following night.
- Use the status pages to keep DIMM status updated