SBIG 16803 Cooling switching off randomly

I bought a SBIG 16803 in mid 2019. You may recall the challenges I had early on with fan vibration. I replaced the fan and the camera has been performing well for me up to now. I now use the camera with a C11 EdgeHD OTA. I use Sequence Generator Pro to manage my sequences and recently during a sequence I notice that the sequence had stopped and there was a message " Waiting on camera temperature……". The camera had been operating at the set temperature of -20C prior to this. The dialogue box for the camera control had previously said -20/-20(60%) where this signifies actual temp C/ setpoint temp C (power consumption %) and the indication said the camera was "on". Now it said NA (0%), although the indicator still said "on". I was able to make a manual intervention by re-entering the setpoint and pressing the cool button, at which time it became clear that the sensor was at ambient temperature and the cooling had to be done from scratch. However, it reached the set point normally and there was no problem from that point on.
However, with the weather being cloudy last night, I was running a sequence to do darks. I do this at night with a black cloth over the OTA in order to ensure no stray light could affect the darks being captured. A half hour ahead of astro dark I turned on the camera and manually set the temperature to -20C within SGPro and the cool down time to 10 mins. This was in order to ensure that the camera was at temperature before the sequence started. The cooling began normally. Some moments later, however, I again noticed that the camera dialogue box saying NA(0%) and that the cooling was “on”. Once again I had to restart the cooling manually, before the sequence start which then proceeded normally.
I made a forum post with Main Sequence, the vendors of Sequence Generator Pro raising this issue. They were unable to identify anything within the sequencing software that would have caused the camera to switch off. And so this evening I decided to see what would happen if I ran the camera through TheSkyX. Once again, I connected the camera and set the set point to -20C and the cooling ramped up. However, before the camera got to temperature the set temperature figure had disappeared and the camera cooling was off. Again I reset the cooling and it was clear the sensor had warmed to ambient, but as with SGPro, once reset the cooling resumed normally. This happened one more time this evening, but the camera has now been running normally for an hour without issue.
This issue is intermittent but is now happening often enough for me to worry about having a sequence bombed out in the middle of the rare clear nights we have here after I have gone to bed and can’t intervene to fix things.
I would appreciate any advice on overcoming the problem.
Yours sincerely,
Niall MacNeill,
Wattle Flat,
NSW,
Australia

 

I'll check that out thanks Colin. The ambient temperature has been between 15C and 20C.

 

I'll checkthat the fan is working alright Doug, particularly if and when I get another of these drop outs. Thanks.

 

Colin, the green light remians illuminated all the time, indicating sufficient voltage. The Red LED is normally illuminated although I have also seen that sometimes it is not illuminated.

 

Doug, the cooling fan is running all the time. I am generally easily able to achieve the set temperature, unless the ambient temperature goes over 26C, whihc it hasn't done for a couple of hours. If that were the case I can connect up my water cooling rig.

Since I wrote this post I have not had the problem.

 

I was monitoring the performance of my SBIG 16803 camera tonight, through Sequence Generator Pro.
The ambient temperature has been steady at about 22C. The camera started up normally. I allow it to get to the set temperature of -20C over 10 mins. Things had been running along fine, for perhaps an hour. I could see the set temperature displayed at -20C and the actual temperature was being well controlled at that with the TEC cooler power

running at 70-75%.

Suddenly I noticed that the actual temperature reading was -13.5C and the power had risen to 100% but didn't seem to be doing anything to the temperature being achieved. A minute later the actual temperature read NA. I aborted the cooling, then set manually set the stepoint to -20C and pressed cool on SGPro. It took 5 mins to get back to temperature and for the image capture process to continue. Unfortunately I was unable to get a screen shot as I was trying to rescue the situation before the sequence was aborted. However, I was able to check that the fan was running on the camera at this time and it was fine. The green light was illuminated and the red one was flashing.
This is clearly an intermittent issue and as such quite frustrating.
If the cooling was shut down due to excessive temperature, I presume the power would have gone off, but I was able to see full power being applied. It seems to me more likely that the temperature probe recording the sensor temperature is occasionally failing and giving out incorrect readings.

What do you make of it?

Thanks & regards,

Niall

 

Thanks for that Colin. Yes SGPro does keep a log. I have looked at these before but didn't find anything terribly illuminating. However, I will have a troll through last night's logs and see if I can find the releveant parts.
The other issue i have been having is a failure to download the image capture and also a failure for the guider images to be downloaded.
To your point that may indicate a usb cable issue.
I also have a new power cable on order from you guys through Bintel, because the old one has some frayed insulation near the plug, where the cable bends as it falls under gravity. A couple of months ago, I put a supporting length of plastic tubing over this section of the cable to reduce the angle of the bend and to better support the cable. Have you see this issue before? Upon seeing this I ordered the new cable.
Here are asome images of what I saw on the screen when i got up this morning. The last of these shows the summary of the log....an abrdiged version of the full log.

Thanks, Niall

 

Hi again Colin, I have already seen the camera cooling shutdown issue when running the camera with TheSkyX, however, I have not run it long enough nor run with guiding to see if the failure to download issue crops up there.
I can do that at the next opportunity. These failures are now consistent enough for such a test to reasonably reliably show the issue...or not.
As I mentioned, lastnight I observed the TEC cooler running along fine , before I then saw the reported temperaure at -13.5C. The cooler power had ramped up to 100% as reported by SGPro. I would have thought the temperature control was done within the camera, so if the issue were a cable issue, why would the reported power consumption have ramped up to 100%. Or perhaps SGPro is varying the power to the camera to achieve the set point temperature? If so a flaky usb cable and corrupted temperature data could cause SGPro to ask for an incorrect power input to the TEC cooler. Please clarify.
Thanks, Niall

 

I understand very well Doug, that when the power draw is 100% that the system is basically not controlling. I did control engineering in my degree. Perhaps you misapprenhended what I said. The system was well in control with the set temperature at -20C and controlling at about that temperature with a power draw of ~ 70% for quite some time. Later when I looked I saw that the actual temperature reading was -13.5C. The control system had naturally wound the power up to 100% to try and achieve this set point, but for whatever reason that was not working. I checked the operation of the fan and could see visually that it was working perfectly. Why the temperature reading had increased to 13.5C I don't know, but shortly after that it read NA as reported by SGPro. I am still unclear as to whether SGPro was controlling the power to the TEC cooler or whether this is being done by the camera with the software merely giving a set point and recording the power draw as reported by the camera. Pleaase confirm which. Or do I need to ask the guys from Main Sequence that? It is my assumption that a switch was activated, probably due to over temeperature, which shut off the power to the TEC cooler to protect the camera. The sensor temperature began to rise and the control system from SGPro was then asking for more power, not knowing the cooler was deactiviated. Subsequently, for some reason the sensor temperature was being reported as NA.

I doubt the input voltage is a problem as I have always seen the green led lit whenever I looked at the camera.

Last night I ran the camera capturing 600 sec images via TheSkyX, as suggested by Colin. I ran it for 6 hours capturing 35 x 600 sec images. The ambient temperature started off around 22C but delined as the night wore on. After 10 captures the control system was still controlling well at -20C and I went to bed. Later on when I got up, 28 images had been captured but the temperature control system was off and no longer controlling at -20C. There was no communication problem either with the camera or the autoguider throughout the run and all the images were downloaded. This suggests there is no problem with the usb2 cable, and that the problems previously observed, related to an inability to download the images, both from the camera and the autoguider are being caused by a problem with SGPro.

However, there is a problem with the temperature control on the camera and it is shutting down during the run, whether the camera is operated by SGPro or TSX. It would be useful if an error message were reported as to why the shutdown had occurred. There is nothing in the SGPro logs to indicate why the camera temperature control is not working, except to say that it isn't. You may recall that I had to change out the stock standard fan to a different, low vibration, but less powerful fan to avoid elongated stars in my images due to vibration. Is it possible that before the power draw get to 100%, the heatsink in the camera is overheating and being shutdown? If so I can try recommissioning my water cooling.

Please advise,

Thanks & regards,

Niall

 

See my response to Doug please Colin.