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ASIAIR + and AM5 intermittent meridian flip failire

ZWO ASIAIR Plus ZWO AM5 Meridian Flip Troubleshooting
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Jeff McClure avatar
Jeff McClure avatar
I just returned from the Eldorado Star Party. On two of the three good nights we had, the ASIAIR+ and AM5 combination failed when it arrived at the meridian. It kept repeating that it was doing a meridian flip and asking me to wait. It went through the attempt over 7 times. I finally got it to flip and return to the target and planned sequence by using the hand controller to send the mount to the home position. I had to do that twice as the first time it returned to the eastern side and locked up again. I took it home with the hand controller a second time and it then did the flip and continued until the end of the sequence. 

Any ideas? I checked all the meridian flip instructions on the Air and the AM5 and they were and are correct.
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Dave Rust avatar
Dave Rust avatar
I have flip troubles about 30% of the time with an ASIair/CEM40 combo. One thing I discovered was that an option to "recalibrate guide scope after flip" was turned on. This sometimes caused the procedure to start at the same time as plate-solving and focusing in plan mode, causing everything to take forever to complete…or fail entirely. The option is found under the mount menu in ASIair. I turned it off. My guide scope is short and rigid. Flex is not an issue, so recalibrating is probably not necessary anyway.

The rig still gets flip failures…but not nearly as often now.

Another bug experienced rarely is that the guiding calibration axis does not always flip with the crossing of the meridian. This causes the image to continuously streak across the guide camera, making plate-solving impossible. As you suggest, homing the scope and returning can help. Or, just manually flipping the axis in the app sometimes works too…though it can take several seconds for the mount to return.

Thought these were worth passing along.
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Maged avatar
Maged avatar
Jeff McClure:
I just returned from the Eldorado Star Party. On two of the three good nights we had, the ASIAIR+ and AM5 combination failed when it arrived at the meridian. It kept repeating that it was doing a meridian flip and asking me to wait. It went through the attempt over 7 times. I finally got it to flip and return to the target and planned sequence by using the hand controller to send the mount to the home position. I had to do that twice as the first time it returned to the eastern side and locked up again. I took it home with the hand controller a second time and it then did the flip and continued until the end of the sequence. 

Any ideas? I checked all the meridian flip instructions on the Air and the AM5 and they were and are correct.



This happens mainly because of day light saving time. AM5 can not understand DST so there will be a time lag between your local time and the UTC.

So, if you are using an IOS device to control the ASIAIR, change the time zone settings of your IOS device to UTC instead of local time and the mount should do meridian flip on time with no issues.
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Quinn Groessl avatar
Quinn Groessl avatar
The only time I've had an issue with a meridian flip with my Asiair and SW EQM-35, was in live stack mode. But that was user error I guess because it doesn't (or at least didn't at the time) flip during live stack mode.
Jim Starek avatar
Jim Starek avatar
I have an AM5 + AAP combo and never had an issue with a Meridian flip. What are your settings for the flip?
I have stop tracking set for 2 minutes prior to the flip and auto flip set to 2 minutes after Meridian. I also have "calibrate guiding after AMF" turned on. I am located in Texas, not sure if your location is an issue? Can it be a power issue? I use a Pegasus 12v 10A power supply for my AM5, and my AAP is powered off my mount. My camera has its own power supply.
One more thing to add. Is your firmware up to date?
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