QHYCCD

QHY268M Cooler at 100% power when the camera is switched ON.

Re: QHY268M Cooler at 100% power when the camera is switched ON.
« Reply #15 on: June 16, 2021, 03:31:12 PM »
Hi,
for me should be ok to set a flag in an .ini file in order to allow the cooler to be off at start-up. However I think this is not a customer requirement, but a camera requirement to avoid thermal stress to the sensor which reduces its life span. I also own cameras from other brands, and these work differently from QHY cameras. When switched on, the cooler is off and a command shall be sent to switch it on. If the USB connection is removed, the cooler continues to operate normally. Furthermore, the logic is not powered by the USB bus but by the 12V power supply via a DC / DC converter. In this way the voltage that feed the logic is always stable regardless of the voltage drop due to the USB cable and does not absorb current from the PC. With only one USB2 port I can power a HUB, the focuser logic, the filter wheel and the guide camera using a 5 + 1 meters of USB cable with no problems. With the QHY268M I have to review the whole configuration because I discovery that it absorbs about 270 mA from the USB2 BUS and this causes instability in the above system, filter wheel reset / focuser reset and cameras hang and it is not possible to work in reliable way.There are also strange messages that Sequence Generator shows (same time) when I try to connect the camera. I will provide the screen shoot when these messages will appear again.

Thank and best regards,
Sergio

Re: QHY268M Cooler at 100% power when the camera is switched ON.
« Reply #16 on: June 16, 2021, 08:29:30 PM »
QinXiaoXu,

Thank-you for your very detailed update. I think your suggestion of adding this function to the qhyccd.ini file is the best solution.

I typically power my camera up without plugging in the USB cable.  I have a powered USB hub at the telescope.  If I then plug in the USB cable between the camera and the powered hub and don't connect the USB hub to my computer this creates a situation where the USB port on the camera has power but cannot communicate to the computer.  Is this the situation you described when you say "If you just connect USB and power, but don't open it via software,the camera still will make cooler work."

Is it possible to have the camera not turn on the cooler in this situation?

For me this is not a problem because I always connect the powered USB hub to my computer first.  The last thing I do is to connect the USB cable to the camera.  This causes the QHY software driver to immediately connect.

Do I understand the issues your have raised?

Regards,

Peter
Hi,
    No,I mean you connect the power and connect USB cable to computer,but not open camera in software.
    And it seem you will opencv camera in software immediately,so it has no influence for you.I will try add it to qhyccd.ini.
Best Regards,
QinXiaoXu
« Last Edit: June 16, 2021, 08:35:13 PM by QinXiaoXu »

Re: QHY268M Cooler at 100% power when the camera is switched ON.
« Reply #17 on: June 16, 2021, 08:37:25 PM »
Hi,
for me should be ok to set a flag in an .ini file in order to allow the cooler to be off at start-up. However I think this is not a customer requirement, but a camera requirement to avoid thermal stress to the sensor which reduces its life span. I also own cameras from other brands, and these work differently from QHY cameras. When switched on, the cooler is off and a command shall be sent to switch it on. If the USB connection is removed, the cooler continues to operate normally. Furthermore, the logic is not powered by the USB bus but by the 12V power supply via a DC / DC converter. In this way the voltage that feed the logic is always stable regardless of the voltage drop due to the USB cable and does not absorb current from the PC. With only one USB2 port I can power a HUB, the focuser logic, the filter wheel and the guide camera using a 5 + 1 meters of USB cable with no problems. With the QHY268M I have to review the whole configuration because I discovery that it absorbs about 270 mA from the USB2 BUS and this causes instability in the above system, filter wheel reset / focuser reset and cameras hang and it is not possible to work in reliable way.There are also strange messages that Sequence Generator shows (same time) when I try to connect the camera. I will provide the screen shoot when these messages will appear again.

Thank and best regards,
Sergio
Hi,
    Yes,its grassroots solution is modify it in FPGA or hardware,but I'm not known its details,I only work on software.You can contact this to Dr.Qiu about this issue,and you also can inquire the unstable system issue.
    And I will wait for your screenshots.
Best Regards,
QinXiaoXu