Teledyne Princeton Instruments Lansis, Системное руководство

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Appendix E Troubleshooting 91
EAR99 Technology Subject to Restrictions Contained on the Cover Page.
E.2 Cooling Faults/Errors
This section provides recommended troubleshooting guidelines for cooling-related
issues.
E.2.1 Temperature Lock Cannot be Achieved or Maintained
CAUTION!
!
The most probable cause of a failure to lock is the setpoint
has been programmed for a temperature lower than Lansis
can achieve. Return the temperature setpoint to the default
value. Protracted operation with an unachievable setpoint
may accelerate TEC failure.
Possible causes for not being able to achieve or maintain lock include:
• Ambient temperature greater than +25°C. If the ambient temperature is greater
than +25°C, either cool the camera’s environment or raise the set temperature.
• Airflow through the camera and/or circulator is obstructed. The camera needs
to have approximately 2” [50.8 mm] of clearance around the vented covers. If
there is an enclosure involved, the enclosure needs to have unrestricted flow to
an open environment. The camera vents its heat out the vents near the nose.
The air intake is near the rear of the camera.
• If using liquid cooling, additional causes for a failure to achieve and/or maintain
lock may include:
— A hose is kinked. Unkink the hose.
— Coolant level is low. Add coolant. Refer to
Section E.2.4, External Coolant
Circulator: Low Coolant (Air in the Hoses) , on page 92.
— There may be air in the hoses. Add coolant. Refer to Section E.2.4, External
Coolant Circulator: Low Coolant (Air in the Hoses) , on page 92.
— Circulator pump is not working. If you do not hear the pump running when
the external chiller is powered on, turn off the circulator and contact
Customer Support. Refer to
Contact Information on page 100 for complete
information.
— The circulator is higher than the camera. Reposition the circulator so that it
is 6” [150 mm] or more below the camera. The vertical distance should not
exceed 10 feet [3 m]. Typically, the camera is at table height and the
circulator is on the floor.
• The camera's internal temperature may be too high which may occur if the
operating environment is particularly warm or when attempting to operate at a
temperature colder than the specified limit. Lansis cameras are equipped with a
thermal-protection switch that shuts the cooler circuits down if the internal
temperature exceeds a preset limit. Typically, camera operation is restored
automatically after approximately ten minutes. Although the thermo-protection
switch will protect the camera, it is nevertheless advised to power down the
camera and correct the operating conditions that caused the thermal-overload
to occur.
• The camera vacuum has deteriorated and needs to be refreshed. Contact
Customer Support. Refer to
Contact Information on page 100 for complete
information.