Cycling Instructions for SPARO Cryostat

Once the SPARO cryostat is cooled to 4He temperature and the external 3He valves have been opened such that the gas has been adsorbed on the pumps(as indicated by a pressure drop on the Ashcroft gauges), the dewar may be cycled. Check to see that the pumped pot is being pumped on and that its temperature is around 1.5K.

Make sure all of the relevant monitoring electronics are connected to the cryocontroller. The standard cryocontroller setup is the following. (See the instructions relating to the setup of the cryocontroller.)

Color Code
TMB 1 Idle - red (solid)
TMB 2 Idle - red (dashed)
TMB 3 Pumped Pot Temperature Ruthenium Oxide Thermometer dark red (solid)
TMB 4 Detector(Inner) Stage Thermometer Ruthenium Oxide Thermometer dark red (dashed)
HWP 1 Half wave plate voltage #1 - cyan (solid)
HWP 2 Half wave plate voltage #2 - cyan (dashed)
Ch. 4 Charcoal pumps temperature Silicon Diode Thermometer orange (solid)
Ch. 5 Idle - orange (dashed)
Ch. 6 OVCS temperature Silicon Diode Thermometer yellow-orange (solid)
Ch. 7 Heater Resistor array magenta (solid)
Ch. 8 Idle - green (solid)
Ch. 9 Idle - green (dashed)
Ch. 10 Pumped pot pressure Capacitance Manometer dark green (solid)
Ch. 11 Detector(Inner) Stage 3He pressure Omega Transducer white (solid)
Ch. 12 Guard(Outer) Stage 3He pressure Silicon diode thermometer white (dashed)

Step 1: Open both heat switches

Step 2: close the valves to the external 3He tanks

Step 3: Heat the charcoal pumps

Step 4: Turn off heaters

Step 5: Close the pumps heat switch

Last Updated February 4, 1999 DTC