Oxford Helium Cryostat

• Wiring Notes

Manuals

On the Internal 11BM Staff staff SVN repository here:

https://subversion.xor.aps.anl.gov/11BMweb/Internal/trunk/staffdocuments/OxfordOptistatCF_HeliumCryostat_Documents/

ordering Liquid Helium

call Mary Berryman (FMS) on 2-3440 by 11 AM the day before to order Helium for next day delivery

normally order 100 L dewer

leave a message if no answer; give name, full cost code, badge number, delivery location (433)

factory default PID info

Wiring Notes

PinDiagram_MaileView_10pin_Winchester.png

Sample Stick A: Auxiliary

Pins A,B,C,D = Phytron Stepper Motor
Motor Phase = Motor Wire  = 10 Pin  = Connector Wire  = Elco  
   1+           red           A           white          A
   2+           blue          B           black          C 
   1-           yellow        C           red            E
   2-           green         D           brown          H
                             
              not used        E
              not used        F
                              
Pins H, J, K, L = Diode Temp Sensor
 Diode   =   Diode Wire  = 10 Pin  = Connector Wire   
  V+        red              H          green       
  V-        white            J          white         
  I+        red/black        K          red         
  I-        white/black      L          black

Sample Stick B: Auxiliary

none 

LakeShore Diode - ITC Sensor 3

Diode = Diode Wire  = DB9 Pin =  ITC  = Connector Wire   
  V+      red           2    Input Low       green       
  V-      white         1    Input High      white         
  I+      red/black     4    Current +ve     red         
  I-      white/black   5    current -ve     black

Sensor 1 Notes

Heaters (x2) + RhFe Resistor

Wiring   
Pin       Function
A  -->    Heater + (x2, running in parallel)
B  -->    Heater -
C  -->    V+ Resistor
D  -->    V- Resistor
E  -->    I+ Resistor
F  -->    I- Resistor
H  -->    ?
J  -->    spare
K  -->    ?
L  -->    ?

Pin Resistance - NEW Cryostat   
Pins        Expected (Ohm)   Measured (April 2011)
A-B  -->    15-25*            36
C-D   -->   30-40             34.5
C-E   -->   < 15              5.2
C-F   -->   30-40             34.6
E-F   -->   30-40             34.6
A-C   -->   > 1 M             open
A-GND -->   > 1 M             open
C-GRN -->   > 1 M             open

* according to Oxford, each heater is 68 Ohm.
Running parallel (1/R1+1/R2 = 1/Rtotal) gives Rtotal expected = 34 Ohms

Pin Resistance - OLD Cryostat   
Pins        Expected (Ohm)   Measured (April 2011)
A-B  -->    15-25             36.5
C-D   -->   30-40             35.5
C-E   -->   < 15              6.0
C-F   -->   30-40             35.5
E-F   -->   30-40             35.5
A-C   -->   > 1 M             open
A-GND -->   > 1 M             open
C-GRN -->   > 1 M             open

Transfer Line

On Cryostat - Inner Dimensions (receptacle on the cryostat)

<------- 38 cm ------->
<- 25 cm -> 
           <- 13 cm -->
///
===========
           ===========
                      ===========
                      ===========
           ===========
===========
\\\

Transfer Line Stick Dimensions (when compression fitting correctly positioned)

<----- 36 cm ----->
       <8 cm > <8 cm >
///
=======
       =======     
              ||====
       =======     ^
=======  ^         |
\\\      |         |
He    return     feed

Python Control Software

SetupCryostat()

in robot.py

Set up Oxford ITC503 Cryostat to default parameters

def SetupCryostat(sensor=2, tries=5)

   sensor: sensor # to control against: 1=gas inlet; 2=cold block (default); 3=spare

   tries: number of repeats to try when sending the command before giving up (default is 5)

GetCryostatT()

in robot.py

Read Oxford ITC503 cryostat temperatures

def GetCryostatT(tries=5)

     input: number of times to attempt read (defaults to 5)

     returns a list of 3 temperatures: sensor1, sensor2, sensor3

SetCryostatT()

in robot.py

Set Oxford ITC503 setpoint and optionally hold for temperature

def SetCryostatT(setpoint, WaitFlag=True, Delay=5, MaxWait=120, DeltaT=2, tries=5):

   setpoint (K) -- desired end T

   WaitFlag (default=True) -- if True the routine will return once the temperature is reached (default), 
                              False means return immediately after setting the ramp to begin

   Delay (min) -- period of time to wait after initially reaching the desired temperature in min (default is 5)

   MaxWait (min) -- maximum period to wait for the selected sensor to reach the Set Point in min.
                    If this period expires, an exception is thrown (defaults to 120)

   DeltaT (K) -- allowed discrepancy between the selected sensor and the desired T to start the delay period (defaults to 2)

   tries -- number of repeats to try when sending the command before giving up (defaults to 5)

SweepCryostatT()

in robot.py

Sets Oxford ITC503 setpoint and optionally hold for temperature

def SweepCryostatT(startpoint, endpoint, sweeptime, WaitFlag=False, MaxWait=1.25, tries=5):

   startpoint (K) -- desired start T for Temp

   endpoint (K) -- desired end T

   sweeptime (min) -- desired time for change from startpoint to endpoint (minutes)

   WaitFlag (default=False) -- if True the routine will return once the temperature is reached,
                               False means return immediately after setting the ramp to begin (default)

   MaxWait (ratio) -- maximum period to wait for the sweep to complete as a ratio of the sweep time.
                      Default is 1.25, meaning to wait 125% of sweeptime,
                      If this period expires, an exception is thrown.

   tries -- number of repeats to try when sending the command before giving up (defaults to 5)

Example Code

s11bmwork% /APSshare/bin/python
Python 2.5.2 (r252:60911, Jan 28 2009, 15:33:22) 
[GCC 4.1.2 20070626 (Red Hat 4.1.2-13)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.path.append('/local/11BMcontrol/MailIn')
>>> import robot
>>> robot.GetCryostatT()
(1.3999999999999999, 407.80000000000001, 273.39999999999998)
>>> 

>>> robot.gui.Sleep(1)
>>> robot.SweepCryostatT(1,2,1)
False
True
False
>>> robot.SweepCryostatT(1,2,1,WaitFlag=True)
True
False
>>> 

Drawings

Oxford_HeliumCryostat_CF1208_drawings.pdf