It is possible as with all complex instruments and electronic systems,
that a time will come when the user encounters a problem, a hangup or a
crash. This section details known problems and how to recover from them
cleanly. Please seek the help of your SA or TO when a problem occurs!
It is likely they have `seen it all before'.
WHIRCAM REFUSES TO STARTUP
THE ALICE OCCAM/TRANSPUTER SYSTEM HANGS/DIES
BDS_ERRCHK> Error while getting ackn from CORE of GO completion - BDS_CORE_SERVER> ERROR: Channel comms timed out on tag receive WFG_OBEYW> Error completing action COMPLETE in 4^^1 task. BDS_CORE_SERVER> ERROR: Channel comms timed out on tag receive !! AIM> After INTEGRATE TASK_DONE SAI-I-ERROR, Error %SAI-I-ERROR, Error 148013867or
BDS_ERRCHK> Error while sending parameter block - BDS_CORE_SERVER> ERROR: Channel comms timed out on tag send WFG_CONFIGURE> Action SEND_PARAMETERS in BDS task failed. - BDS_CORE_SERVER> ERROR: Channel comms timed out on tag send !! ALICE_DONE> Action failed to complete in WFG : STATUS = SAI-I-ERROR, Error ! ALICE_DONE> Returned OUTVAL =BDS_CORE_SERVER> ERROR: Channel comms timed out ! on tag send !! AIM> After CONFIGURE TASK_DONE SAI-I-ERROR, Error %SAI-I-ERROR, Error 148013867
What is happening is that the BDS gets a command (to say, GO) and sends
this onto the CORE transputer system. This should be, and is,
acknowledged. When the observation completes, the CORE has to send an
acknowledgement to the BDS that the (GO) completed successfully - it is
this acknowledgement that the BDS never receives (e.g. ackn from CORE of
GO completion). This is a sure sign that the Occam is hanging for some
reason - the subsequent error:
(starting BDS_ERRCHK;SPMgt; Error while sending parameter block ...)
is a further indication that the Occam side cannot communicate with anything else.
ALICE_CONFIG <CR> ALICE_OCCAM <CR>This will re-load the Occam/Transputer side.
THE ALICE/TELESCOPE LINK HANGS/DIES DURING A SLIDE
If no flashing light, then type SET PROC/PRIV=ALL in WHIRCAM's SMS window,
then type UCX. At the UCX prompt, type `ping cgs' which checks for a response
from ALICE. If no response, then something is likely wrong with either
the ethernet, the B300, or IRCMVX ethernet. Call a duty tech.
THE WHIRCAM MOTOR DRIVES FAIL
Replacing the failed motor drive is the obvious solution, but so as
to avoid losing a large fraction of the night, there is an option of
running WHIRCAM without motor control, in which all the other functions
will continue as normal, but filter changes will have to be done by hand.
In this case, close down WHIRCAM, and restart with `whircam_manual'
instead of `whircam_start'. The motor drives sit on the back of the
WHIRCAM cryostat, and when not powered (switch off the drives in
the GHRIL console area), can be rotated by hand. The datum position
(position 1) is marked on the drive wheel, and each new position (in the
direction of the arrow) can be felt by hand as you rotate the wheel.
While this may be time consuming and laborious, real astronomers prefer
this than to going to bed early.
HIGH DARK CURRENT
If any temperatures aren't nominal, then the He in the closed cycle
cooler may be low, and needs to be topped up. Call the Duty Tech.
HIGH READOUT NOISE
Display_port = 1 Data_area = DATA Number_of_bins = 50 X_step = 4 Y_step = 1 Smooth_size = 0 Soft_or_hard_copy = SOFT Display_whole_area = FALSE _xstart_if_not_whole = 1 _ystart_if_not_whole = 1This should plot a histogram of the first transputer readout in the upper left quadrant of the image display. To display the second transputer readout, reset Display_port to 2 (shifts to the next display quadrant in upper right) and _xstart_if_not_whole to 2. Repeat for the third and fourth transputer readout. You should then end up with 4 histograms, one per display quadrant. They should be all about the same mean, with widths of typically a few counts. If one is noticeably wider, then check the cable for that transputer (in the ALICE rack in the GHRIL control room) to make sure it isn't loose. If the SA doesn't know which cable belongs to which transputer (eg the brown cable is channel 4), you'll have to disconnect each in turn, repeat array_tests and re-plot the histograms to see which one changes.
If all cables seem to be OK, then it may be that one of the ADC cards is
broken. Spare cards exist, so call your Duty Engineer.
MISALIGNMENT OF WHIRCAM AND/OR DICHROIC
If the dichroic was moved, then you must tweak the micrometers to re-align it: