Specifications
Also notice the yellow line in the graph – it displays camera internal
temperature. This temperature also somewhat grows as the cooling
utilization grows. The hot air from the Peltier hot side warms up the camera
interior slightly.
How fast can be the chip cooled? Can be the chip damaged, if it is cooled
too fast? Unfortunately the maximum speed of temperature change is not
defined for Truesense Imaging CCD chips (at last the author does not know
about it). But in general slow temperature changes cause less stress to
electronic components than rapid changes. The SIPS temperature change
speed default value is 3 °C per minute. It is usually no problem to switch the
camera earlier and to provide time for slow cooling. However, if it is
necessary to cool the camera rapidly, alter the “Max. dT” value.
It is also easier to achieve higher temperature differences if the temperature
is changed only slowly. Switching the Peltier cooler from zero to 100%
immediately provides a lot of heat and, especially in the case of air-cooled
Peltier, the overall camera temperature can raise more than necessary. The
result is the chip temperature is higher in absolute numbers, because the
hot-side temperature is also higher. It takes long time before the hot side
slowly settles.
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Illustration 13: “Cooling” tab of the CCD Camera Control tool