Mach1 and GTOCP4 Yellow Light


Mikko Viljamaa
 

This started a week ago when I would suddenly get a Yellow warning light with a random slew when connecting the mount with the SGP. My first thought was that the control unit has condensated again but I was wrong and it turned out to be bone dry. Next I tried to fiddle the power and the Y cable and that helped and the next few days were fine. Last night the mount had violently slewed again so my I’m thinking now that I have a faulty cable.

I ordered both new cables but I am wondering now is there anything else I should check before changing those cables tomorrow before a clear night again?


- Mikko


Dean Jacobsen
 

Check the input voltage to the CP4.
--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Roland Christen
 

Make sure you have enough voltage from your battery or power supply, and that you have nothing else running off that supply. Make sure that your cable from the power source is as short as possible. Long cables lose a lot of voltage between supply and the mount controller.

Rolando



-----Original Message-----
From: Mikko Viljamaa <mikko.viljamaa@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 7, 2020 3:03 pm
Subject: [ap-gto] Mach1 and GTOCP4 Yellow Light

This started a week ago when I would suddenly get a Yellow warning light with a random slew when connecting the mount with the SGP. My first thought was that the control unit has condensated again but I was wrong and it turned out to be bone dry. Next I tried to fiddle the power and the Y cable and that helped and the next few days were fine. Last night the mount had violently slewed again so my I’m thinking now that I have a faulty cable.

I ordered both new cables but I am wondering now is there anything else I should check before changing those cables tomorrow before a clear night again?


- Mikko


Christopher Erickson
 

There is also some mysterious limits function in the CP4 that I have encountered in the past that I don't yet fully understand when using the CP4 and just the hand controller. It might manifest in other control scenarios as well. Basically, one day my Mach1 with CP4 wouldn't slew very far to the East (or West. I forget.) before the power light would go yellow and not let me slew farther. This was on a solid 13.6V 10A power supply. No hanging cables or other mechanical snags or problems. Cycling CP4 power got the red light back but as soon as I would try to slew into the "forbidden zone" the light would go yellow again. The mount was finding things in the sky everywhere else just fine and time/date/location/TZ info in the hand controller all looked fine. I tried a couple of "resume from Park X" procedures and suddenly the problem vanished and I could not duplicate it. I suspect that some safety limit variable was out of sync in the CP4, but I was unable to reproduce the problem to study it.

It has resurfaced about every other month or so on my Mach1/CP4 and the solution seems to be to do one or more CP4 power cycles and "Resume from Park X" procedures to get whatever variables inside the CP4 that are managing safety slews resynchronized with the rest of the CP4 code.

I shared this info with the AP CP4 programmer but I didn't hear back if he was able to reproduce the problem and/or get it figured out and fixed.

And of course there is always the chance that somehow I was unknowingly causing the problem and there isn't a mystery horizon limit bug in the current CP4 code.  

I hope this helps.

Virus-free. www.avg.com


On Tue, Jul 7, 2020 at 10:41 AM uncarollo2 <chris1011@...> via groups.io <chris1011=aol.com@groups.io> wrote:
Make sure you have enough voltage from your battery or power supply, and that you have nothing else running off that supply. Make sure that your cable from the power source is as short as possible. Long cables lose a lot of voltage between supply and the mount controller.

Rolando



-----Original Message-----
From: Mikko Viljamaa <mikko.viljamaa@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 7, 2020 3:03 pm
Subject: [ap-gto] Mach1 and GTOCP4 Yellow Light

This started a week ago when I would suddenly get a Yellow warning light with a random slew when connecting the mount with the SGP. My first thought was that the control unit has condensated again but I was wrong and it turned out to be bone dry. Next I tried to fiddle the power and the Y cable and that helped and the next few days were fine. Last night the mount had violently slewed again so my I’m thinking now that I have a faulty cable.

I ordered both new cables but I am wondering now is there anything else I should check before changing those cables tomorrow before a clear night again?


- Mikko


Mikko Viljamaa
 
Edited

I have everything running from the same power unit, this since the day 1 two years ago. Nothing has changed and everything else still works fine. I’m not planning to have a separate power for the mount alone.


- Mikko


Christopher Erickson
 

Try one or more CP4 power cycles and "Resume from Park X"

Virus-free. www.avg.com


On Tue, Jul 7, 2020 at 11:28 AM Mikko Viljamaa <mikko.viljamaa@...> wrote:
I got everything running from the same power unit, this since the day 1 two years ago. Nothing has changed and everything else still works fine. I’m not planning to have a separate power for the mount alone.


- Mikko


Cheng-Yang Tan
 

Well, it does no harm by checking whether it is a power supply problem. They have been known to fail. First thing is to put a multimeter on it and make sure it's spitting out the correct voltage. The second thing is to just power up the mount *without* any of your accessories/gear to see whether you have the yellow light. If you don't, then you know it is the power supply.

cytan

On Tuesday, July 7, 2020, 04:29:39 PM CDT, Mikko Viljamaa <mikko.viljamaa@...> wrote:


[Edited Message Follows]

I have everything running from the same power unit, this since the day 1 two years ago. Nothing has changed and everything else still works fine. I’m not planning to have a separate power for the mount alone.


- Mikko


Dean Jacobsen
 

Have you measured the voltage that is getting to the mount?
--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


W Hilmo
 

I’ve had power supplies fail.  I’ve also had cables and connectors fail.

 

It’s worth checking.

 

From: main@ap-gto.groups.io <main@ap-gto.groups.io> On Behalf Of Mikko Viljamaa
Sent: Tuesday, July 7, 2020 2:28 PM
To: main@ap-gto.groups.io
Subject: Re: [ap-gto] Mach1 and GTOCP4 Yellow Light

 

[Edited Message Follows]

I have everything running from the same power unit, this since the day 1 two years ago. Nothing has changed and everything else still works fine. I’m not planning to have a separate power for the mount alone.


- Mikko


John A. Sillasen
 

Dean suggests: "Check the input voltage to the CP4."  That is exactly what I was going to suggest as well.


John A. Sillasen



Roland Christen
 

Yes, slewing into the fixed limit will turn on the yellow light. Send the mount back to Park3, manually orient the axes to Park3 position, and you are good to go.

Rolando



-----Original Message-----
From: Christopher Erickson <christopher.k.erickson@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 7, 2020 4:17 pm
Subject: Re: [ap-gto] Mach1 and GTOCP4 Yellow Light

There is also some mysterious limits function in the CP4 that I have encountered in the past that I don't yet fully understand when using the CP4 and just the hand controller. It might manifest in other control scenarios as well. Basically, one day my Mach1 with CP4 wouldn't slew very far to the East (or West. I forget.) before the power light would go yellow and not let me slew farther. This was on a solid 13.6V 10A power supply. No hanging cables or other mechanical snags or problems. Cycling CP4 power got the red light back but as soon as I would try to slew into the "forbidden zone" the light would go yellow again. The mount was finding things in the sky everywhere else just fine and time/date/location/TZ info in the hand controller all looked fine. I tried a couple of "resume from Park X" procedures and suddenly the problem vanished and I could not duplicate it. I suspect that some safety limit variable was out of sync in the CP4, but I was unable to reproduce the problem to study it.

It has resurfaced about every other month or so on my Mach1/CP4 and the solution seems to be to do one or more CP4 power cycles and "Resume from Park X" procedures to get whatever variables inside the CP4 that are managing safety slews resynchronized with the rest of the CP4 code.

I shared this info with the AP CP4 programmer but I didn't hear back if he was able to reproduce the problem and/or get it figured out and fixed.

And of course there is always the chance that somehow I was unknowingly causing the problem and there isn't a mystery horizon limit bug in the current CP4 code.  

I hope this helps.

Virus-free. www.avg.com

On Tue, Jul 7, 2020 at 10:41 AM uncarollo2 <chris1011@...> via groups.io <chris1011=aol.com@groups.io> wrote:
Make sure you have enough voltage from your battery or power supply, and that you have nothing else running off that supply. Make sure that your cable from the power source is as short as possible. Long cables lose a lot of voltage between supply and the mount controller.

Rolando



-----Original Message-----
From: Mikko Viljamaa <mikko.viljamaa@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 7, 2020 3:03 pm
Subject: [ap-gto] Mach1 and GTOCP4 Yellow Light

This started a week ago when I would suddenly get a Yellow warning light with a random slew when connecting the mount with the SGP. My first thought was that the control unit has condensated again but I was wrong and it turned out to be bone dry. Next I tried to fiddle the power and the Y cable and that helped and the next few days were fine. Last night the mount had violently slewed again so my I’m thinking now that I have a faulty cable.

I ordered both new cables but I am wondering now is there anything else I should check before changing those cables tomorrow before a clear night again?


- Mikko


Eric Claeys
 
Edited

I have the same issue on my Mach1 and 1100 GTO with encoders, and even talked to George about it once when it was happening.  We were able to get the mount working by issuing some commands to the mount via the terminal interface, but then the problem would happen again at some point.  I could never figure out a pattern.
The version of APCC I was using when this happened about 1.5 years ago didn't give any indication the light was on (I only knew because I noticed slews weren't working), and I don't know if the current version of APCC does, but it sure would be nice for APCC to pop up an error message when this happens.
The light would go on with slews via software (SGP in my case) or the hand controller.  I have a CP4 on both mounts.
When it happens, I can slew one direction but not the other.

In my case it wasn't any apparent limit, like horizon limit.  It would usually occur near the meridian, and once it was fixed, it would slew into the no-slew zone without any problems.


Christopher Erickson
 

Sounds familiar. It was as if the horizon limit on one side was suddenly up near (or at) the meridian.

In my case all I have connected is the AP hand controller and no other computers or smart devices.


-Christopher Erickson
Observatory engineer
Waikoloa, HI 96738
www.summitkinetics.com
   


On Tue, Jul 7, 2020, 4:21 PM Eric Claeys <AstroEric@...> wrote:

[Edited Message Follows]

I have the same issue on my Mach1 and 1100 GTO with encoders, and even talked to George about it once when it was happening.  We were able to get the mount working by issuing some commands to the mount via the terminal interface, but then the problem would happen again at some point.  I could never figure out a pattern.
The version of APCC I was using when this happened about 1.5 years ago didn't give any indication the light was on (I only knew because I noticed slews weren't working), and I don't know if the current version of APCC does, but it sure would be nice for APCC to pop up an error message when this happens.
The light would go on with slews via software (SGP in my case) or the hand controller.  I have a CP4 on both mounts.
When it happens, I can slew one direction but not the other.

In my case it wasn't any apparent limit, like horizon limit.  It would usually occur near the meridian, and once it was fixed, it would slew into the no-slew zone without any problems.


Mikko Viljamaa
 

Thanks for the comments and recommendations.

OK, what’s the easiest way to measure the voltage to the mount? I think I have a multimeter somewhere. I did end up buying another power source from Amazon yesterday just in case I need to replace the existing one. Also, it sounds like the Y-cable is not probably the culprit here.

As said, in my case the Yellow light comes on immediately when the mount is powered on. I have yet to have a case where if the sequence has started OK the mount would have malfunctioned.


Mikko

 


Dean Jacobsen
 

Mikko, if the probes of your multi-meter are small enough then you should be able to just unplug the power cable from the CP4 and measure the voltage at the connector.  Turn on you power supply and all of the other accessories that you said also you run from the power supply and measure the voltage at the CP4 connector.  Then turn off all of the accessories and measure the voltage at the CP4 connector again.

A question for Roland and Ray:  is it possible to have the AP ASCOM driver read and report the CP4 and CP5 input voltage?
--
Dean Jacobsen
http://astrophoto.net/wp/
Image Gallery - http://astrophoto.net/wp/image-gallery/
Astrobin - https://www.astrobin.com/users/deanjacobsen/ 


Roland Christen
 

I will investigate this issue and get back to you all.

Roland Christen
Astro-Physics Inc.



-----Original Message-----
From: Eric Claeys <AstroEric@...>
To: main@ap-gto.groups.io
Sent: Tue, Jul 7, 2020 9:19 pm
Subject: Re: [ap-gto] Mach1 and GTOCP4 Yellow Light

I have the same issue on my Mach1 and 1100 GTO with encoders, and even talked to George about it once when it was happening.  We were able to get the mount working by issuing some commands to the mount via the terminal interface, but then the problem would happen again at some point.  I could never figure out a pattern.
The version of APCC I was using when this happened about 1.5 years ago didn't give any indication the light was on (I only knew because I noticed slews weren't working), and I don't know if the current version of APCC does, but it sure would be nice for APCC to pop up an error message when this happens.
The light would go on with slews via software (SGP in my case) or the hand controller.  I have a CP4 on both mounts.
When it happens, I can slew one direction but not the other.


Roland Christen
 

If the yellow light comes on immediately, then you probably have a bad connection from the CP4 to one of the two motor gearboxes. It could be your Y cable, or it could be inside the gearbox. Most likely is the connection to the RA motor. Normally the RA motor starts tracking upon power up. You can see that if you look at the end of the motor shaft, at the spur gears. If the motor does not start rotating, then within a few seconds the CP4 will shut power off and turn on the yellow light, indicating a motor stall condition. So, your first order of business is to find out if this is what's happening.

Rolando

-----Original Message-----
From: Mikko Viljamaa <mikko.viljamaa@...>
To: main@ap-gto.groups.io
Sent: Wed, Jul 8, 2020 8:36 am
Subject: Re: [ap-gto] Mach1 and GTOCP4 Yellow Light

Thanks for the comments and recommendations.
OK, what’s the easiest way to measure the voltage to the mount? I think I have a multimeter somewhere. I did end up buying another power source from Amazon yesterday just in case I need to replace the existing one. Also, it sounds like the Y-cable is not probably the culprit here.

As said, in my case the Yellow light comes on immediately when the mount is powered on. I have yet to have a case where if the sequence has started OK the mount would have malfunctioned.


Mikko
 


Ajay Narayanan <ajynrynn@...>
 

I had exactly the symptoms you describe with an AP900 and a CP3 controller. I called AP from the field and George's advice was to spread the prongs of the central pin of the power connector. I don't know if that applies to your CP4. I also notices that the battery terminals were a little corroded. So I spread the prongs with a pocket knife and cleaned the battery terminals. One of those fixed the issue and resulted in the controller seeing the correct voltage.

Ajay


Roland Christen
 

The CP4 has a different power connector. There are no pins to spread. The advice to spread pins does not apply to the CP4.

Rolando



-----Original Message-----
From: Ajay Narayanan via groups.io <ajynrynn@...>
To: main@ap-gto.groups.io
Sent: Thu, Jul 9, 2020 10:57 am
Subject: Re: [ap-gto] Mach1 and GTOCP4 Yellow Light

I had exactly the symptoms you describe with an AP900 and a CP3 controller. I called AP from the field and George's advice was to spread the prongs of the central pin of the power connector. I don't know if that applies to your CP4. I also notices that the battery terminals were a little corroded. So I spread the prongs with a pocket knife and cleaned the battery terminals. One of those fixed the issue and resulted in the controller seeing the correct voltage.

Ajay


Mikko Viljamaa
 

Well I changed the power unit first yesterday and that didn’t help. Neither did the power cord and actually at this point the mount even refused to connect. So I had not high hopes when I changed the Y cable but miracles happen and with the new Y cable everything worked fine last night. 

This until an hour ago when I tried to start a sequence again only to run into the same problem again. When the mount is connected, the RA axes immediately slews about 20 degrees after which it stops and the yellow light is on. 

If I try to open the RA gearbox tomorrow, what exactly should I look for?


- Mikko