Question M-Due Won't Track - RA shows "Upper Limit Hit"

I think my mount may have slewed one more revolutions the wrong way, now it says "Upper Limit Hit" for RA and won't Track. How do I know which way and how many turns to rotate it to get back to where it needs to be, or is there a way to reset the limits?

Hi Jethro,

While I have not encountered this issue with my M-Uno & the SG2, you could check the configuration section in the web-based interface to the mount. In a browser, type in the IP address of the SG2.

I’ve done that, it only shows what the limits are set to. I need to know what the mount currently thinks it’s at. I’ve tried loosening the clutch and manually spinning the mount in RA a few rotations in either direction but it still reports as being at the upper limit.

Hi. Now I understood. Tricky. Try checking the mount drivers & settings via an INDI interface, such as iINDI on iOS/iPadOS or KStars/EKOS on any other OS. Maybe you find something there. PhD2 has also an INDI interface, where you can connect to the remote INDI server on the StarGO2 and connect/enable to all the driver settings.

This is just a guess. I do not have the encoders, but often I have to go through this interface to check or to fix settings. Besides the actual mount driver there is also the AUX driver… not sure where the encoder settings are displayed or stored.

I used VNC Viewer which shows me the front panel display, and looking at that it does show the current Az and Alt readings in degrees. And when I rotated by hand to near the meridian I see this:



What I don't understand is why it still says upper limit hit when the range set in the configuration is from 255 to -255 degrees.

Actually, as I sit here looking at the display, I'm noticing some odd behavior. If the mount were tracking I'd expect RA and DEC to remain constant (mostly) while Az and Alt would be constantly changing. And if the mount were still I'd expect RA and DEC to be constantly changing while Az and Alt remained constant. However the opposite is happening. The mount is still but RA and DEC are constant while Az and Alt are changing, this is very odd.