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chara:trouble_shooting [2021/11/04 18:59]
charaobs [Metrology and Homing carts]
chara:trouble_shooting [2021/11/04 23:53]
charaobs [Can't find fringes]
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   * Were the clocks synced? Make sure the [SYNC CLOCKS] button on Cosmic Debris has been pushed to start the night. If the OPLE server does not display the correct CHARA time and the errors don't read (0) or (1), the clocks were not synced.   * Were the clocks synced? Make sure the [SYNC CLOCKS] button on Cosmic Debris has been pushed to start the night. If the OPLE server does not display the correct CHARA time and the errors don't read (0) or (1), the clocks were not synced.
-  * Did the Astrolib update on OPLE? If the job queue is stopped too soon after slewing on Cosmic Debris, the correct calculations for the carts will not be done by OPLE and you may be searching for fringes with the wrong star data. Hit STAR ACQUIRED on CD to update ople. The proper star can also be entered by typing hd #### into the OPLE server and hitting ENTER.+  * Did the Astrolib update on OPLE? If the job queue is stopped too soon after slewing on Cosmic Debris, the correct calculations for the carts will not be done by OPLE and you may be searching for fringes with the wrong star data. Hit STAR ACQUIRED on CD to update ople. The proper star can also be entered manually by typing hd #### into the OPLE server and hitting ENTER.
   * Are the PoP's correct? After a PoP change, the PoP's are sometimes not updated in CD or ople.   * Are the PoP's correct? After a PoP change, the PoP's are sometimes not updated in CD or ople.
-  * Are the carts behaving or are there vibrations or jumps of 100 or more microns every 3-6 seconds? Restart the ople server if they persist.+  * Are the carts behaving or are there vibrations or jumps of 100 or more microns every 3-6 seconds? How are the metrology signals? Are they strong and staying white? Red signals mean one or more metrology signals may have gone too low and homing carts is necessary.  The METDATA function on the ople gui can be used to sample the metrology signal and may show noise spikes that can be disruptive to the smooth cart motion. Push the METDATA button on the configure tab and then again about 6 seconds later.  Plots will pop up to show the frequency and power of any noise.
   * Is the target a high proper motion star? Red dwarfs are close stars and can have high proper motions. Scan a wider range to see if it is outside of the usual calculated scan range. Binaries can also have very high offsets from the expected position due to mistakenly using astromod calculations from the companion star.   * Is the target a high proper motion star? Red dwarfs are close stars and can have high proper motions. Scan a wider range to see if it is outside of the usual calculated scan range. Binaries can also have very high offsets from the expected position due to mistakenly using astromod calculations from the companion star.
-  * Do you have enough flux from each telescope or on each baseline?+  * Do you have enough flux from each telescope or on each baseline?  Is the telescope tiptilt struggling with low flux?  Can the camera gain be raised or the exposure made longer to help hold the star?
   * Did you get the same star in each telescope? Sometimes a busy star field and poor pointing of the telescopes can lead to the wrong star being acquired and locked by tiptilt. View the stars in the finder window to see if all the stars match.   * Did you get the same star in each telescope? Sometimes a busy star field and poor pointing of the telescopes can lead to the wrong star being acquired and locked by tiptilt. View the stars in the finder window to see if all the stars match.
   * Check the CHARA time on the GPS server. The "Ext-CHARA," "CHARA-Sys," and "Ext-Sys" time offsets listed on the GPS server should be small (< 0.01 sec). If there are large time offsets, then a GSYNC might be needed.   * Check the CHARA time on the GPS server. The "Ext-CHARA," "CHARA-Sys," and "Ext-Sys" time offsets listed on the GPS server should be small (< 0.01 sec). If there are large time offsets, then a GSYNC might be needed.
   * Check the time on the OPLE server. If the time is off or there are any lost ticks/seconds "Lost T/S" listed, then MSYNC ople using the GPS GUI and type "syncople" into the ople server.   * Check the time on the OPLE server. If the time is off or there are any lost ticks/seconds "Lost T/S" listed, then MSYNC ople using the GPS GUI and type "syncople" into the ople server.
   * Are the [MAN] buttons pressed (gray) for the moving carts on the OPLE Control gui? (The reference cart will remain green.)   * Are the [MAN] buttons pressed (gray) for the moving carts on the OPLE Control gui? (The reference cart will remain green.)
-  * Check that the carts are within delay line range (-1 to 44 meters) and errors are small. Were the carts homed before the first slew of the night? Did any carts go to the front switch after slewing? This can cause them to lose their position. Turn off the OL button to send it back to zero. If it does not track on the home switch when displaying a zero position (0.000000), it was lost. Is the E2 cart stuck at 27.97m? How are the metrology signals? Are they strong and staying white? Red signals mean one or more metrology signals have gone too low and homing carts is necessary. See section on homing carts in __OPLE and Metrology__  section below.+  * Check that the carts are within delay line range (-1 to 44 meters) and errors are small. Were the carts homed and checked before the first slew of the night? Did any carts go to the front switch after slewing? This can cause them to lose their position. Turn off the OL button to send it back to zero. If it does not track on the home switch when displaying a zero position (0.000000), it was lost. Is the E2 cart stuck at 27.97m? See section on homing carts in __OPLE and Metrology__  section below.
   * Are the LDC's working?   * Are the LDC's working?
       * Is the glass position within allowable range (-10mm to 49mm) on all beams?       * Is the glass position within allowable range (-10mm to 49mm) on all beams?
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       * If LDCs are working correctly, the LDC positions (in mm) should roughly match up with the reference cart positions (in meters).       * If LDCs are working correctly, the LDC positions (in mm) should roughly match up with the reference cart positions (in meters).
  
-  * Check the instrument alignment. Is flux getting through to the detector? How long has it been since the last NIRO camera alignment? Classic and CLIMB programs can run for about an hour before the light will drift from the central pixel. Use the Classic or CLIMB gui to view the light on the pixels by clicking the PICTURE tab and then the PIXEL AREA button. Turn the camera off after a few seconds to avoid crashing NIRO. Is the right dither power turned on? CLIMB 1 and Classic use different dithers. If Classic or CLIMB fringes are found in a scan, but not when in recording mode, the dither powers are likely not on. Are the camera settings correct for the seeing conditions and flux levels?+  * Check the instrument alignment. Is flux getting through to the detector? How long has it been since the last NIRO camera alignment? Classic and CLIMB programs can run for about an hour before the light will drift from the central pixel. Use the Classic or CLIMB gui to view the light on the pixels by clicking the PICTURE tab and then the PIXEL AREA button. Turn the camera off with the STOP button. Is the right dither power turned on? CLIMB 1 and Classic use different dithers. If Classic or CLIMB fringes are found in a scan, but not when in recording mode, the dither powers are likely not on. Are the camera settings correct for the seeing conditions and flux levels?
  
  
chara/trouble_shooting.txt ยท Last modified: 2024/06/18 00:21 by charaobs