APCC issue? Mach2 motor stall error when running APPM #Mach2GTO


Shailesh Trivedi
 

I have configured horizon and meridian limits for a scope combination. I changed the image train (now it is much longer), when running a pointing model using APPM, I think the scope hit the pier and I got a motor stall error in APPM (not 100% sure but a strong suspicion). 

Question: Once I reconfigure meridian limits for my new scope/image train, does running a new pointing model ensure the scope will not hit the pier if the new meridian limits are configured?

Shailesh


Ray Gralak
 

Hi Shailesh,

Question: Once I reconfigure meridian limits for my new scope/image train, does running a new pointing model
ensure the scope will not hit the pier if the new meridian limits are configured?
Are you mapping counterweight-up points in your APPM runs? If so, it is very important to have the meridian limits set correctly. If you are not mapping counterweight-up points then the redoing meridian limits will not make a difference.

-Ray


Shailesh Trivedi
 

On Sun, Apr 24, 2022 at 11:24 AM, Ray Gralak wrote:
Ray,

Maybe I am not understanding why during an APPM run I got a motor stall warning. I looked at my APPM settings, the CW Up slews is not checked. I also could not find the motor stall warning text in the log file(s) but all subsequent plate solves after that warning failed. I think I recall clearing that warning or error from the onscreen messages.

So should I do something different?


Ray Gralak
 

Shailesh,

So should I do something different?
APCC/APPM cannot cause motor stalls. There are various reasons for a motor stall so give Mike at A-P a call tomorrow unless Mike sees this and posts some suggestions.

-Ray


Shailesh Trivedi
 

Reporting back. Last night I ran APPM with a small model of 32 stars successfully. It was short enough that I stayed there to watch what happens. I think I know why there were motor stalls.

I redefined my Meridian Limits for my new scope and long imaging train but this does not matter to APPM as it does not use the meridian limits (why?)

While running the small model I realized what must have caused motor stalls. For my Mach2, I have bolted the CP5 to the west side of the Losmandy HD tripod and hence when the mount slews the scope to the west side of the pier close to zenith, it comes within approximately 1 inch of the protruding CP5. And this is my theory of why it caused a motor stall when the scope hit the CP5 (ouch).

Now I plan to relocate my CP5 to be behind the RA axis (on the south side of the pier). Is this a safe spot?

Shailesh


Roland Christen
 


Now I plan to relocate my CP5 to be behind the RA axis (on the south side of the pier). Is this a safe spot?
Yes, this is the safest spot, and it's where I locate mine.

Rolando


-----Original Message-----
From: Shailesh Trivedi <shailesh.trivedi@...>
To: main@ap-gto.groups.io
Sent: Mon, Apr 25, 2022 5:27 pm
Subject: Re: [ap-gto] APCC issue? Mach2 motor stall error when running APPM #Mach2GTO

Reporting back. Last night I ran APPM with a small model of 32 stars successfully. It was short enough that I stayed there to watch what happens. I think I know why there were motor stalls.

I redefined my Meridian Limits for my new scope and long imaging train but this does not matter to APPM as it does not use the meridian limits (why?)

While running the small model I realized what must have caused motor stalls. For my Mach2, I have bolted the CP5 to the west side of the Losmandy HD tripod and hence when the mount slews the scope to the west side of the pier close to zenith, it comes within approximately 1 inch of the protruding CP5. And this is my theory of why it caused a motor stall when the scope hit the CP5 (ouch).

Now I plan to relocate my CP5 to be behind the RA axis (on the south side of the pier). Is this a safe spot?

Shailesh

--
Roland Christen
Astro-Physics


Greg McCall
 

I'd be curious to see a picture of the CP5 mounted to the pier bit of the losmandy mount.
Mine is currently in another location so can't get to it at the moment but I made up a spacer, from memory about 20m long, and replaced one of the losmandy pier attachment screws that secure the short pier to the tripod legs, with a longer screw and use that to secure the CP5 supplied bracket.


Ray Gralak
 

Hi Shailesh,

 

> I redefined my Meridian Limits for my new scope and long imaging train but this does not matter to APPM as it

> does not use the meridian limits (why?)

 

Is the checkbox labeled “Use APCC Meridian Limits” on the "Measurement Points" tab not working? (See screenshot):

 

 

-Ray


Shailesh Trivedi
 

Ray,

Honestly, I have not checked. I will double-check it.

@Greg I will try to image it and attach it here.

@Roland let me see if there is an available slot to screw the CP5 holder.

Shailesh


Greg McCall
 


Dean Jacobsen
 

That is where my CP5 goes too.  My pier extension isn’t as tall though.
--
Dean Jacobsen
Astrobin Image Gallery - https://www.astrobin.com/users/deanjacobsen/


Shailesh Trivedi
 

Thank you all for your feedback. I relocated my CP5 to the south side of the pier as Dean and Greg have. 

After that, I was successfully able to run a 200+ point APPM model.

Ray the Meridien Limits checkbox in APPM has no impact. If I had not relocated my CP5 and left it on the west side of the pier, it would definitely have collided with the pier/CP5 causing a motor stall. Perhaps something to investigate.

Shailesh


Ray Gralak
 

Shailesh,

Ray the Meridien Limits checkbox in APPM has no impact. If I had not relocated my CP5 and left it on the west
side of the pier, it would definitely have collided with the pier/CP5 causing a motor stall. Perhaps something to
investigate.
Can you provide more details? The meridian limits checkbox allows for mapping counterweight-up points by making the last slew in RA only to counterweight-up positions.

I assume this is for mapping counterweight up points with a properly configured the limits on both sides of pier? (which you should have done with the Meridian limits explorer),

It might be helpful if you could share a screenshot of the APPM mapping-points window.

-Ray