Hello,
I just bought a WD-20 ago from my dealer in Germany and used it for the first time yesterday. However had a couple of issues particularly during polar alignment:
I had the mount in Home position roughly towards north celestial pole, took a plate solve in NINA, and afterwards started 3 Point polar alignment in NINA.
Then the mount started to slew the telescope to the west on the RA, however suddenly went back and forth with the RA axis, and this back and forth continued for minutes, and switching off the mount was the only way to finally stop it. I noticed this behaviour on two or 3 polar alignment runs yesterday (I can also provide a short video, if helpful)
On further polar alignment runs, where this back and forth did not happen, I also received an error message after the run saying something like the mount did not move far enough to reach the targe distance for the next point, which is due to the limits of the mount or the mount’s driver rate implementation (I do not 100% recall the exact wording). The telescope after the polar alignment run was also noticeably close to the tripod… could the mount maybe have noticed that and therefore not haved moved further?
Following the polar alignment run, the tracking also stopped 1 or 2 times, and I was not able to reactivate tracking in NINA.
Could you please provide support to the points mentioned above?
From the behavior of the issues you mentioned. It should be the AEB(Automatic Emergency Braking) safety feature of mount triggered, may due to the sensitive of default threshold for your OTA weight and slewing speed.
Please check if the firmware version of your mount is 20.21W, or you had upgraded it to that. You can use the hand controller->Settings->Firmware ver. or PC mount tool to check it.
For solve this issue and avoid reverse protection easily triggered, you can use the mount PC tool to change the aggressiveness of AEB, for larger value to avoid happen.
Hello,
many thanks for the fast response.
I checked the Hand controller, and I indeed had current firmware version 20.21W.
But I had previously not downloaded the mount PC tool… I have now done so and adjusted the parameters you mentioned.
Will try Polar alignment again in next imaging session, and will let you know if problem is solved.
Many thanks,
Roman
unfortunately I still had some problems with 3 Point polar alignment in the last imaging session. I had disabled the EAB and the EC HA limit in the mount tool, while keeping the overhead and horizon limits as big as possible (see attached screenshot with the settings I took).
The issue with the mount slewing back and forth did not occur, but the mount still did not make sufficient movements to obtain a good polar alignment (there still seems to be a limitation somewhere).
Furthermore I tested the slewing of the mount on both axes in my living room (see the 2 videos attached).
Starting from the Home position, when slewing the RA axis to the West, a complete shutdown of the mount occurs over and over again, when slewing ca 45 degrees west. The mount will be completely turned off and only after ca 2 minutes it will be possible to switch it on again. Is that a normal behaviour?. Interestingly, this does not occur when slewing the RA axis to the East from Home Position in the same angle.
A further weird behaviour, which I observed, was when I slewed the declination axis from the Home position with the N button. When trying to return the DEC axis to Home position with the S button, the DEC axis kept on moving, as if I had pressed the N button.
Please see the two videos attached, which show what I described above.
Can you please let me know if the behaviour of the mount described above is something you would expect?
From the video showing that mount suddenly lost power. It may due to power supply issue. Please check your power supply if able to provide 12V 5A output.
The mount will demand more power during slewing. It needs power >12V and some power bank may not to provide stable voltage with a voltage dropping at high current.
For this, it’s a normal behavior of DEC axis. as your mount at home position pointing NCP/SCP. It’s the polar define the North and South direction of the mount. Refer to detailed explanation on OnStep Wiki. main@onstep.groups.io | Wiki
Many thanks, you were actually right. After changing the cable, the shutdown of the mount does not occur any longer. @Warpastron: I am sorry but the cable that was provided to me along with the mount, was indeed faulty and there was a small gap when connecting it to the mount.
Thanks for the response.
It was indeed the cable. When replacing it with another cable, the problem did not occur any longer.
It seems that the cable that was provided to me along with the mount, had some issue.
Might I ask another question: Where can I adjust the guide rate for the mount? And what guide rate would you recommend for Auto-Guiding in PHD2 with this mount?
