Mimir Warm-Up Procedures v1.0 (DPC) 2017016
Steps to follow to safely warm up Mimir from cold operations conditions.
Contents
Mimir Warm-Up Procedures
Restart Yggdrasil telemetry of Mimir temperatures and pressures
Set the detector on a warming ramp from 33.5K to 80K
Change the Yggdrasil crontab to cease BA Vacuum Gauge measurements
Trap gunk in the Cold Head
Set the Compressor Data Logger to not send email/text warning messages

Restart Yggdrasil telemetry of Mimir temperatures and pressures

If Mimir has come off the telescope, or the telemetry has stopped because of power outage or similar, restart may be necessary, as follows:

  1. Check if the temper program is running
    1. On Yggdrasil, "ps –ef | grep temper".
    2. If it is not running, then in the camera home directory, enter "start.temper"
    3. Check again to see if it is running.
  2. Check if the program to serve out the Mimir status web page is running, restart if necessary
    1. On Yggdrasil, "ps –ef | grep idl"
    2. If it is not running, go to the directory "/home/camera/Web/status/wwwfiles"
    3. Remove all the html and png files
      1. "rm *.html"
      2. "rm *.png"
    4. Change directories to "/home/camera/Web/bin"
    5. Launch the web page server by entering "./mimirwww"
      1. Check that it is running by entering "ps –ef | grep idl"
      2. If it is not running, then invoke IDL by entering "idl", then after it launches, exit IDL and retry launching mimirwww.
  3. Verify all is running by looking at the Mimir status web page on lux, then from a computer looking at iar.lowell.edu for the web page. If both work, all is well.
    1. Occasionally, the lux Mimir web page is good, but it is not being served from iar.lowell.edu. This generally indicates problems with iar or problems with communications off the Mesa. Consult the Lowell IT folks in this instance.


Set the detector on a warming ramp from 33.5K to 80K

On the Lake Shore LS331 unit (the temperature controller), set the temperature ramp rate to 0.2 K/min and the setpoint to 80K, by doing the following:

  1. Press the "Loop" button (lower right on the LS331 panel) until the "Control B" light turns on. (It may already be on)
  2. Press the "Control Set-Up" button (left, top row on front panel)
  3. The display will read: "Select for Loop 2" in the top row and "Control w/ Input B" in the bottom row.
    1. If the bottom row reads something else, press "Escape" and do step 1.1.1 again.
  4. Hit "Enter". The display bottom row will now show "SP Units Temp K".
  5. Hit "Enter". The display bottom row will now show "Control Mode Closed"
  6. Hit "Enter". The display bottom row will now show "Power Up Enabled"
  7. Hit "Enter". The display bottom row will now show "Setpoint Ramp On"
  8. Hit "Enter". The display bottom row will now show "Ramp Rate 0.1K/m"
  9. Press the "0", ".", and "2" keypad keys to change the ramp to 0.2 K/m and hit "Enter".
  10. The display bottom row should change to "Ramp Rate 0.2K/m"
  11. Press the "Setpoint" button (left, bottom row)
  12. The display bottom row should show "Setpoint 33.5K"
  13. Using the keypad, enter "80.0" and hit "Enter"
  14. The display should change to "Setpoint 80.0K"
  15. The "Ramp" light should slowly flash to indicate that the control Setpoint is now moving at 0.2K/min from 33.5K to 80K, and the instantaneous value of the setpoint temperature is shown in the display bottom row next to the "S:". (the power being supplied to the detector heater is indicated in the bottom row as the "L2:" value in percentage of 1 Watt.


Change the Yggdrasil crontab to cease BA Vacuum Gauge measurements

The Yggdrasil computer normally turns the BA vacuum gauge on for 15 min around 5pm and 7am, using the crontab. This must be reconfigured to not do so while Mimir is warm (and the vacuum is likely not present, or at least not adequately deep).

  1. Log into Yggdrasil, via the camera account
    1. If VNC does not work:
      1. Log into Yggdrasil with putty or equivalent, using the camera account. If on Saturn, open a terminal window and "ssh camera@yggdrasil"
      2. When logged in, type "vncserver" and hit enter. It should come back informing you that VNC connections are now open on port 1 (aka 5901).
  2. View the current crontab, by entering "crontab –l" (crontab minus ell). There are two sections, one that is 'live' and one that is commented out (for cooldowns).
  3. To edit out the live part, enter "crontab –e" (to edit the crontab)
    1. This is a VI-like editor. When done, enter ":wq" (colon write quit). Crontab automatically updates and continues.


Trap gunk in the Cold Head

The goal here is to keep any gunk in the helium system trapped in the cold head, so as to keep the rest of the helium system clean and pure. Once the detector temperature is at 80K, it is safe to turn off the cooling system.

  1. Find two box wrenches (NOT adjustable spanners) used for removing helium hoses from the cold head (they have yellow tape around one end of their handles).
  2. Do the following in quick order (no dallying!)
    1. Unplug the power connector to the cold head motor (located above and between the two helium hose fittings on the cold head). The motor will cease moving.
    2. Using the two wrenches, unscrew the green, supply helium line fitting with one wrench while using the other wrench to keep the hose from turning.
    3. Do the same for the red, return helium line fitting
    4. Turn off the helium compressor
    5. Cap the helium hoses


Set the Compressor Data Logger to not send email/text warning messages

The data logger in the compressor shed is normally set to send error messages if the compressor stops or the shed gets too warm or too cold. These messages need to be suppressed when the compressor is turned off.

  1. From within the Lowell.edu domain, open an instance of the Hyperware-II software
  2. Select the "Logger" option on the top row, then in the pull-down menu, select "Logger Connection"
    1. The Compressor connection should be the only line shown in the table in the pop-up window
    2. If this is a new install of Hyperware-II from Logic Beach, the connection to the logger must be established.
      1. Click the "Add" button.
      2. Enter the name and IP address of the logger
        1. "Compressor" and "10.12.100.112" and the port number is "4660"
  3. In the pop-up window, click the "Connect" button
  4. Rather than edit the running program, it probably makes the most sense to just stop the program by clicking the "Stop" word on the picture of the logger in the displayed computer window.
  5. This requires double-clicking with the mouse over the "Stop" button, then answering "Yes" to the pop-up.
  6. Note that Mimir status web page will now have stale values for all of the compressor shed annunciator line (the lines with colors just below the Detector/Optics/Vacuum line of colored bars).
  7. Select the "Logger" option on the top row again, and "Logger Connection" and then click the "Disconnect" button and the "Close" button.
  8. Select "File" and then "Exit".
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