Practical guide of the temperature switch between nitrogen and helium

Consult beamline scientist before changing any temperatures

The cryocooler is highly sensitive. To obtain an accurate temperature reading, please adhere to the following instructions. Note that the temperature change occurs gradually, so be patient! It requires time to reach the desired temperature.

Temperature panels at beamline

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300K --> 15K : Room Temperature to base (change N2 to He flow)

  • Step 1 : Go to the Gas Prep User Interface tab
  • Step 2 : Look for Gas Prep Macro User Interface tab

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  • Step 3-a : Run prepswitch

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  • Step 3-b : Change the flow_set 12

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  • Step 4-a : Looks at the QM2 dashboad and check until the temperature of the channel A and C is stabilize to ~100K and ~96K

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  • Step 4-b : In User Interface tab, put target temp (te) 240 (# set the sample temperature to 240K)

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  • Step 5: You need to wait until the temperature of the sample is 240K (Make sure you do not have ice)
  • Step 6-a : Turn on the Helium (He) valve and close nitrogen (N2) valve together, as soon as you do that run the next command

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  • Step 6-b : Go to the Gas Prep User Interface tab
  • Step 6-c : Run runninghelium (# it will setup the temperature in the Lakeshore controller)

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  • Step 6-d : Change the flow_set 17

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  • Step 6-e: Spin the crystal at the bottom of the User Interface with Start (# rotate sample 360-->0 and 0-->360 degree in phi directions)

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  • Step 8-a : Wait for base temperature (Input A ~9K Input C ~55K) to stabilize

  • Step 9 : Stop Spin Control

  • Step 10-a : Put target temp (te) 15 (# set the sample temperature to 15K)
  • Step 10-b: Spin the crystal Start until it achieved desired temperature

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  • Step 11: Stop Spin Control

Data Collection in the helium condition

Data Collection 15K --> 110K : in the helium condition

  • Step 1 : Go to Low Temp Scan tab
  • Step 2 : Change Start temp, End temp, Step size, Spin cycle/step - steps in between temperature
  • Step 3 : Click Preview
  • Step 4 : Click Run Low Temp Scan

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15K --> 300K : Heating temperature of cryocooler (change to He to N2 flow)

  • Step 1-a : User Interface 'Gas Prep' tab, Run prepswitch (# it will setup the temperature in the Lakeshore controller channel A = 100K and channel C = 95K)
  • Step 1-b : User Interface 'Gas Prep' tab, target temp (te) 240 (# set the sample temperature to 240K )
  • Step 1-c: User Interface 'Gas Prep' tab, flow_set 13
  • Step 2 : Make sure all the temperatures (channel A, B, C) are above 80 K --->(Input 1 (A) >96 K, Input 2 (sample temperature)>200K and Input 3 (C) 85K in PLD controller)
  • Step 3 : Send message to SLACK channel once all the channels (A,B.C) are above 80K and before switching it to nitrogen from helium

Danger

N2 in all conditions should be above 80K (N2 (channel A, B, C) --> all temperature-->80K)

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  • Step 4 : Turn on the N2 valve and close He valve together
  • Step 5-a : User Interface 'Gas Prep' tab, roomT (# it will setup the temperature setpoints 222K and 220K in the Lakeshore controller Input A and input C and it will to reach the temperature 100K and 146K.)
  • Step 5-b: User Interface 'Gas Prep' tab, flow_set 10
  • Step 6 : User Interface 'Gas Prep' tab,target temp (te) 300 (# increase temperature to 300K or any other desired temperature)

Data Collection in the helium condition

Data Collection 120K --> 300K : in the helium condition

  • Step 1 : Go to Warmup tab
  • Step 2 : Change Start temp, End temp, Step size, Spin cycle/step - steps in between temperature
  • Step 3 : Cick Enable
  • Step 4 : Click Preview
  • Step 5 : Click Run Warmup

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Nitrogen to helium switch : Please use Helium sensibly!

130K --> 15K : Cooling temperature of cryocooler with helium (He)

  • Step 1: FOURC > prepswitch (# set temperature to Input 1 (A): 100K and Input 3 (C): 95K in screen 3; Input 1 (A) > 90, Input 1 (A) >85 are the good number to switch from N2 to helium)
  • Step 2 : FOURC > te 240 (# set the sample temperature (Input 2) to 240K - green plot at screen 1) If the ice did not melt go to te 260
  • Step 3 : FOURC > flow_set 10
  • Step 4: You need to wait until the temperature of the sample is 240K (it might be lower temperature)
  • Step 5 : Turn on the Helium (He) valve and close notrogen (N2) valve together, as soon as you do that run the next command

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  • Step 6 : FOURC > runninghelium (# it will setup the temperature in the Lakeshore controller)
  • Step 7 : FOURC > flow_set 12
  • Step 8 : Wait for base temperature Input 1 (A) ~5K Input 2 (C) ~44K to stabilize
  • Step 9 : FOURC > te 15 (# To go to desired temperature (te) )
  • Step 10: FOURC > spin_xtal_phi (# rotate sample 360-->0 and 0-->360 degree in phi directions)
  • Step 11: FOURC > control C ; you can STOP rotation; DONOT run control C twice, the program will crush

15K --> 130K: Heating temperature of cryocooler (change to He to N2 flow)

  • Step 1 : FOURC > prepswitch (# it will setup the temperature setpoints 100K and 95K in the Lakeshore controller Input A 100K and input C 95K)
  • Step 2 : FOURC > te 240 (# it will setup the desired sample temperature; here sample temperature is 240 K)
  • Step 3 : Make sure all the temperatures (channel A, B, C) are above 80 K --->(Input 1 (A) >96 K, Input 2 (sample temperature)>200K and Input 3 (C) 85K in PLD controller)
  • Step 4 : Send message to SLACK channel, please provide A, B, C channel temperature

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Danger

N2 in all conditions should be above 80K (N2 (channel A, B, C) --> all temperature-->80K)

  • Step 5 : Once Input A, B and C are above 80K, then open the N2 valve and close He valve together

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  • Step 6 : FOURC > te 135 (# increase temperature to 135K or any other desired temperature)

300K --> 500K : Performing experiment at high temperature

  • Step 1 : Talk to beamline scientist, also send message to SLACK channel during temperature change
  • Step 2 : Make sure N2 valve is open and He is closed
  • Step 3 : FOURC > highT
  • Step 5: Make sure in the controller Input 1 (A): 300K and Input 2 (C): 300K, it will to reach that temperature and stabilize close to A 107K and C 196K.
  • Step 6 : FOURC > flow_set 6
  • Step 7 : FOURC > te 480 (# temperature will go tho maximum 480K)

500K --> 300K : Performing experiment at high temperature

  • Step 1 : Talk to beamline scientist, also send message to SLACK channel during temperature change
  • Step 2 : Make sure N2 valve is open and He is closed
  • Step 3 : FOURC > roomT
  • Step 5: Make sure in the controller Input A: 222K and B input C: 220K, it will to reach that temperature and stabilize close to A 105K and C 190K.
  • Step 6 : FOURC > flow_set 6
  • Step 7 : FOURC > te 300

Danger

Talk to beamline scientist before going high temperature

300K --> 500K : Performing experiment at high temperature when compressor need to turn off

  • Step 1 : Talk to beamline scientist, also send message to SLACK channel during temperature change
  • Step 2 : Make sure N2 valve is open and He is closed

  • Step 3 : Physically Turn off compressor (Go to the end of the hutch)

  • Press off in the compressor (see the image below), send a message to the SLACK channel (this will help to track the compressor status and equipment condition)

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  • Step 4 : FOURC > te 300
  • Step 5: FOURC > turn_off_compressor (# increase temperature to 1st and 2nd controller to 300K and 300K)
  • Step 5: Make sure in the controller 1 (Input A: 300K and B input C: 300K), it will to reach that temperature and stabilize.
  • Step 6 : FOURC > flow_set 6
  • Step 7 : FOURC > te 480 (# increase temperature to 400K)

Note: Above 480K, it took long time to go 498K

500K --> 300K Performing experiment from high temperature to room temperature when compressor need to turn off

  • Step 1 : Talk to beamline scientist, also send message to SLACK channel during temperature change
  • Step 1 : Make sure N2 valve is open and He is closed

  • Step 2 : Physically turn on the compressor (Go to the end of the hutch)

  • Press on in the compressor (see the image below), send a message to the SLACK channel (this will help to track the compressor status and equipment condition)

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  • Step 3: FOURC > roomT (# increase temperature to 1st and 2nd controller to 130K and 110K)
  • Step 3 : Make sure in the controller Input A and Input C, it will to reach the temperature 101K and 110K.
  • Step 4 : FOURC > te 300 (# increase temperature to 300K)

Turn off the temperature controller

  • Step 1 : Heat the temperature 300K, 300K, 300K
  • Step 1 : Stop all the heaters manually in Lakeshore controller
  • Step 2 : Turn off the compressor
  • Step 3 : Wait until go to the required temperature
  • Step 4 : Close the Nitrogen valve once A, B, C are 300K

Problem : Ice formation at low temperature

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  • a) Figure 1 : Check the distance between the cryo-stream and sample (it should be as close as possible)
  • b) Figure 2 : Continuously rotate the phi umv phi 360; umv phi 0 at low temperature

  • c) Figure 3 : Check the gas flow and if needed talk to the staff scientist

    • FOURC> flow_set <number>
    • FOURC> flow_get

Problem : High temperature issues

  • a) Figure 3 : Check the gas flow and if needed talk to the staff scientist

Problem : Accidentally closed the temperature controller

  • Step 1 : Open terminal and type StripTool

  • Step 2 : Connect to epics PVs

  • Need to connect to epics PVs that you want to monitor

    • LAKESHORE2:KRDG0
    • LAKESHORE2:KRDG1
    • LAKESHORE2:KRDG2

  • y-axis click “Modify” button (same y axis for all the curves)

Emergency proceduce if the temperature controller fails or Sudden power failure at beamline

Talk to Beamline Scientist or operators --- DONOT TRY THIS WITHOUT ASKING

  • If the your setup is in nitrogen condition (300K - 80K) and suddenly temperature is dropiing drastically and you don't have controls
  • Switch the valve Nitrogen to Helium

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  • Closed the compressor

  • Change the EPIC PVs range