Hi guys, I am operating a Veloce 200RH in Spain remotely, and we are using an SBIG ST8300M camera with it since a few years without issues. However since a few days we have a weird problem: Upon setting the temperature in the (ST8300m) camera to (e.g.) -10C the cooler cools down the chip to the desired temperature in a few seconds. However after a few moments the cooler starts working harder to maintain the same temperature until it reaches 100%. At that point the temperature rises and rises and rises (despite the cooler working at 100%) until I turn the cooler off again altogether. I am baffled as all has been perfectly well until two nights ago... It looks like the camera is unable to dissipate the heat it produces during cooling. The fan is working fine, and the heatsink is clean and doesn't feel hot or something. I would guess that maybe there is a gap between the peltier element and the heatsink? If so, could we fix this somehow ourselves or do we need to return it for repair? Your help would be very much appreciated! All the best, Harel and Lukas
If the fan is working then the cooler stack must have become disconnected somehow. That's extremely unusual. There is a device for applying pressure on the stack to ensure good contact; perhaps it has broken somehow. Sounds like it needs to go in for service. Bill is off for a bit for holidays, but you can contact him at bill@sbig.com
HI Doug, thanks for your quick answer. Is there anything between the Peltier and the heatsink, like some glue (like on the heatsinks of modern CPUs, where there is a thermic conducting paste on it)? Maybe it dried up or the likes...
There are several connections in the stack, and I believe that design has both thermal paste and a thermal pad. We use good materials; I've never seen one dry up.
Hi Doug, I am sure you use good materials and I agree that this is very strange. Maybe the best would be to return it for inspection, as we truly are unable to understand what is going on. It cools for a few minutes, and then heats up up to around 30°C (with air temperature around 0°C). I really can only think this being due to the heat being unable to get away from the TEC...
Yes that sounds absolutely correct. The TEC must not be making good contact with the heat sink. Best not to run the cooler if it's doing that; there is a risk of overheating it. Please contact Bill @ service.
I'm just another customer, with a suggestion. Like Joshua says, check the power supply with a voltmeter. If that is okay, then here is one more suggestion: ONLY if you are okay with doing delicate work - otherwise, you might want to send it for repair. Check if the power connector in the camera has a problem - it might not make good contact. You can put a tiny flat jeweller's screwdriver in there and expand the two halves of the centre pin. Do this carefully - don't break the connector pin. This may help make better contact with the centre hole in the power connector from the power supply. Good luck.
