CryoTel® GT User’s Manual Version 6 P a g e | 14
X. CryoTel® Operation
CRITICAL! – Do not operate the cryocooler without adequate cooling at the heat rejection
site. Overheating the cryocooler will cause permanent damage.
A. Preparation
1. Attach application apparatus or test cap assembly to cold tip of cold finger.
a. Apply a thin layer of Apiezon thermal grease or Indium to the copper tip of the cold finger in
order to maximize conductivity.
2. Attach the customer-provided cryostat by appropriate means if a vacuum is required for the
application.
3. If using a vacuum, make wire connections from temperature sensor and any other measuring
devices inside the cryostat through Dewar feedthroughs.
a. For maximum performance, wires should not touch the walls of the Dewar. Contact with
walls will increase the heat loading (conduction) during use and will yield lower available
cooling power.
4. Seal the cryostat vacuum except for the connection to the vacuum pump (if using vacuum).
5. Mechanically attach the cryocooler assembly to the customer provided mounting device.
6. Connect the wiring from the cryostat feedthroughs to the appropriate test and measurement
devices.
a. The cold tip temperature sensor must be connected to the controller’s mating connector as
described previously using the provided connector (See Figure 10 for controller
connections).
7. Attach the vacuum pump to cryostat, start the vacuum and allow it to reach a vacuum of 10
-4
Torr or
better.
B. Beginning Operation
1. Prepare the CryoTel® GT for testing as described above.
2. Connect the cryocooler power cables for the CryoTel® GT to the controller’s power terminal block.
The orange wire should be connected to pin 2 (OUT +). The white wire should be connected to pin 1
(OUT -). (Controller connections shown in Fig. 13).
a. IMPORTANT! Verify the correct polarity is observed with respect to the CryoTel® GT –
orange power cable wires are positive, white wires are negative. Inversed polarity could
result in damage to the Cryocooler.
3. Connect the controller to a 48V
DC
power outlet. Connect +48V to the power terminal block pin3
(IN+). Connect the power return (ground) to pin 4 (IN-).
a. IMPORTANT! Verify the correct polarity is observed. Inversed polarity will result in
damage to the controller.
b. Note: Crimp ferrules should be used on wire ends connecting to the terminal block. The 14
Gauge ferrules are available at Digikey PN 288-1101-ND. The proper tool for crimping the
ferrules is Digikey PN 288-1163-ND.
c. The controller has a startup sequence that positions the piston in the axial center. This
sequence takes approximately 7-10 seconds once the controller is turned on.
d. The controller then applies a 60 Hz AC voltage to the motor, creating the oscillating motion
of the piston that begins the cooling process.
e. The controller increases the power to the cryocooler based on cold end temperature. The
maximum draw by the controller is approximately 300 W
E
.
4. Allow cold tip temperature to stabilize at desired cold end temperature.
To Next Page
Loading...
Need help?
General
