Hi Doug I have an old STL11000M which is struggling to maintain its cooling. Its Summer here so the camera can only maintain about -5 degrees, but now I am seeing the cooler temp being gradually raised as the cooler power gradually climbs to 100%. I captured a log and it clearly shows this ramp up of cooler power and the cooler temp being 'backed off' to compensate. Eventually the camera is at +5degrees and cooler power at 100%. I am guessing the TEC is failing or has failed? thanks martin
Martin - while we wait for @Doug or @Bill to comment, quick tips (you've probably done much of this already): - check the fan is operating - check the heatsink and fan are clean. - check the vent slots are clear. Sometimes they just get gunked up with dust over time, and that will cause TEC issues. Check the power supply voltage LEDs to make sure they are normal, and not low power. The power supply capacitors do age and then they can become problematic. TECs will eventually weaken and sometimes the circuitry that powers it will fail/weaken as the capacitors wear out or heat gets to it. Then @Bill would have to see what he can do to repair it.
It's unusual for TECs to fail unless they get exposed to water (e.g. tons of moisture in the chamber), but that's not the only potential cause. The issue could be mechanical or electrical in nature. Bill can do certain electrical repairs, and can of course handle anything mechanical.
Martin, Definitely check the Fan. If it's not working then the heat from the back side of the cooler doesn't get dissipated, the camera gets warmer and cooling % increases to compensate. It'll eventually get to 100% and the ccd temperature will continue to rise. If the fan is working and it's a matter of the camera only reaching -5, then it depends on what the starting temperature was. The average deltaT (maximum cooling capacity) for the STL cameras was around 35 degrees of which the camera can regulate 80-85% of. For an example, if you're starting at +25, max cooling would get you to -10. 80% of 35 is 28 so you can only expect to regulate at around -3. And if the fan isn't working... A way you can determine the delta T is to first let the camera sit a while so that it equalizes with the ambient temperature. Indoors on the kitchen table, I'd expect the starting temp to b around 22 or 23. Then power up, connect (CCDOps is good for this because it shows the starting ambient temperature as soon as the link is established) and note the starting temperature. Set the cooling to -50 and watch the temp decrease until it won't go any lower. Note that temp and do the math. If the delta is in the 32-35 range then that would be considered "normal". It should only take about 5-10 minutes to do this. If the delta T is below that "spec", then it's possible that the cooler isn't cutting the mustard any longer (depending upon how far below it is). It's not common but it's not unheard of either. All the best, Bill
Thank you very much for the swift replies. Indeed, the fan has failed and having liaised with Bill I have managed to order a compatible replacement here in Australia. regards Martin P.S Any news on new camera releases?
