Andor Technology Zyla sCMOS 4.2 PLUS, Руководство по оборудованию

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version 2.0 rev 18 Feb 2021
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4.3 Cooling
4.3.1 Integral Thermal Protection
Care should be taken to ensure that the camera does not overheat, as this can cause system failure.
Overheating may occur if either of the following situations arises:
Air-cooled Models
• The air vents on the sides of the head are accidentally blocked
• The ambient air temperature is more than 30ºC (Zyla 5.5*), or 27ºC (Zyla 4.2)
*For Zyla 5.5 models manufactured prior to February 2015 max. ambient is 35ºC.
To protect the camera from overheating, a thermal switch has been attached to the heat sink. If the temperature
of the heat sink rises above predefined limit then the current supply to the cooler will cut out and a buzzer will
sound. To reset this, it is necessary to exit the software and switch off the camera, correct the issue, let the system
cool then restart the camera and software.
Water-cooled Models
• The coolant system is not operating correctly
To protect the camera from overheating, a thermal switch has been attached to the heat sink. If the temperature
of the heat rises above predefined limit then a buzzer will sound. To reset this, it is necessary to exit the software
and switch off the camera, correct the issue, let the system cool then restart the camera and software.
4.3.2 TE Cooling (Air-Cooled Models)
The Zyla sCMOS sensor is cooled using a thermoelectric (TE) cooler. TE coolers are small, electrically powered
devices with no moving parts, making them reliable and convenient. A TE cooler is actually a heat pump, i.e. it
achieves a temperature difference by transferring heat from its ‘cold side’ (the CMOS-chip) to its ‘hot side’ (the
built-in heat sink). Therefore the minimum absolute operating temperature of the Zyla sensor depends on the
temperature of the heat sink. The maximum temperature difference that a TE device can attain is dependent
on the following factors:
• Heat load created by the Zyla sensor (dependant on pixel readout speed)
• Number of cooling stages of the TE cooler
• Operating current
• Hot side temperature of thermoelectric cooler
Even with a fan, a heat sink typically needs to be at least 10ºC hotter than the air (room) temperature to
transfer heat efficiently to the surrounding air. Therefore during normal operation the temperature of the
heatsink within the camera head will be warmer than the ambient (room) temperature.
4.3.3 TE Cooling (Water Cooled Models)
For water cooled models the dissipation of heat from the TE cooler is achieved by circulating coolant liquid
through the heat sink. The high specific heat capacity of water provides efficient heat dissipation, allowing the
sensor to be operated at -10ºC. Benefits of water cooling include:
1. Reduced vibration as there is no cooling fan required, which may be useful for ultra-sensitive
measurements and
2. Improved dark current.