Princeton 4300 User Manual

Chapter 7 

Troubleshooting 

69 

 

 

69 

Operating a PI-SCX:1300 camera with coolant at a temperature colder than specified 

could cause induced condensation in the electronics enclosure and possible catastrophic 

damage to the camera. Damage resulting from this type of operation may void the 
warranty. 

Possible causes could include: 



 

Ambient temperature greater than +23°C. If it is greater than +23°C, you will need to 

cool the camera environment or raise the set temperature.   



 

The vacuum has deteriorated and needs to be refreshed. 



 

The connectors of the cable that interconnects the controller and the camera need to 

be secured.   



 

The target array temperature is not appropriate for your particular camera and CCD 

array.   



 

For cameras that are liquid-cooled or have liquid-assisted cooling, the coolant flow 

rate may be insufficient due to a pinched coolant line, blockages, circulator power 

problem, or pump failure. Check the flow rate and coolant temperature.  



 

For a TE-cooled camera, the camera's internal temperature may be too high, such as 

might occur if the operating environment is particularly warm or if you are 

attempting to operate at a temperature colder than the specified limit.  TE-cooled 

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 in about ten minutes. Although the thermo-protection switch 

will protect the camera, you are nevertheless advised to power down and correct the 

operating conditions that caused the thermal-overload to occur.  

The internal temperature of the camera is too high. This might occur if the operating 

environment is particularly warm or if you are trying to operate at a temperature colder 

than the specified limit. If this happens, an internal thermal overload switch will disable 

the cooler circuits to protect them. Typically, camera operation is restored in about ten 

minutes. Although the thermal overload switch will protect the camera, users are advised 

to power down and correct the operating conditions that caused the thermal overload to 

occur. With some versions of the software, the indicated temperature when the camera is 
in thermal overload (thermal switch is in the cut-out state) is -120° C.

  

With time, there may be a gradual deterioration of the camera’s vacuum. This can affect 

temperature performance such that it may be impossible to achieve temperature lock at 

the lowest temperatures. In the kind of applications for which cooled CCD cameras are so 

well suited, it is highly desirable to maintain the system’s lowest temperature 

performance because lower temperatures result in lower thermal noise and better the 

signal-to-noise ratio.  
Vacuum deterioration occurs primarily as a result of material outgassing in the vacuum 

chamber. Because outgassing normally diminishes with time, the rate of vacuum