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Equipment Discussions >> Mounts

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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
CG5 declination motor just stopped working!
      #5308207 - 07/08/12 12:33 PM

I have a Celestron C8 on a CG5 Advanced Series Go-To mount. It has been working wonderfully for me for three years now, especially after a DIY Hypertune two years ago.

Last night I was at a star party for the ALCon2012 convention. My second star party this week. My mount worked perfectly fine at the Wednesday night star party and was working fine the first half of last night's star party.

At one point, someone asked if I could slew to the moon since it had finally just cleared the trees on the horizon. I punched the command into my scope and off it went. Except it was widely off track. The RA axis was moving as it should, but the DEC axis not moving at all. I tried slewing to a different object, and the same thing happened. RA motor would slew and track but the DEC motor wouldn't move a millimeter. After the scope would come to a stop after slewing in the RA, it would just sit there. The hand controller still had the spinning thing in the display indicating that it was still trying to slew even though it wasn't moving anymore.

I turned off my mount and moved back to the index marks. Started the mount back up and tried to perform a two-star alignment. No go. The RA would move but not the DEC. I unplugged and replugged in the DEC cable from both ends and tried again. No go. I repeated this cycle a couple more times to no avail.

Eventually, I grew tired of messing with it and decided to just start hand-pointing my scope to targets and letting the RA axis continue its tracking. It made for a VERY slow rest of the night at the star party. Star hopping with an inoperable CG5 mount is tedious and slow!

So, anyone have any ideas what may be causing my issue? Is my DEC motor burned out? Is there loose connections in the DEC port? Bad DEC cable? I won't have any time to pull it apart and start looking at it for a few days. So I'm hoping to get some ideas from y'all in the meantime. Thanks!


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ourobouros2k2
sage


Reged: 11/10/11

Loc: okc area, oklahoma
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5308215 - 07/08/12 12:42 PM

I would try the dec. board first, then cabling, then look at the motor itself. All the parts are available through the support section spare parts shop. It is possible for the wires from the dec motor to the dec board can become "unstuffed" and pinch during movement. I had to tape mine down.

Good luck,
Andy

Edited by ourobouros2k2 (07/08/12 12:43 PM)


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rdandrea
Carpal Tunnel
*****

Reged: 06/13/10

Loc: Colorado, USA DM59ra
Re: CG5 declination motor just stopped working! new [Re: ourobouros2k2]
      #5308239 - 07/08/12 01:02 PM

Did you get a No Response Error 17? Typically, you will get this error if the cable or motor control board is bad. It means the hand controller can't talk to the declination motor control board. If you didn't get this error, I'd be looking elsewhere, like the motor itself or, as the previous poster suggested, the wiring from the board to the motor.

And by "not move," do you mean you can't hear the motor running at all, or just that the scope is not moving?


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RTLR 12
Post Laureate
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Reged: 12/04/08

Loc: The Great Pacific NorthWest
Re: CG5 declination motor just stopped working! new [Re: ourobouros2k2]
      #5308243 - 07/08/12 01:08 PM

RobbW,

You should check the connections of the Dec motor first. Make sure that the Dec cable is full seated in the sockets at both ends. You should also look into the sockets and insure that the wire contacts are clean and properly aligned. If you have the capabilities, check the Dec cable for continuity. The RJ12 connectors are known to have connection issues. If you have the crimping tool or know someone that does, try re-crimping or replacing the connectors. The next thing you will want to check is the connections from the MC board to the power board and the connection from the Dec board in the Dec cover to the motor. You can swap the Dec and RA motor connectors on the motor board and see what results you get. If the dec motor runs, but the RA motor is now inop, then the problem is with the board. If the Dec motor still doesn't run the problem is with the Dec motor or connections.

Stan


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Starhawk
Space Ranger
*****

Reged: 09/16/08

Loc: Tucson, Arizona
Re: CG5 declination motor just stopped working! new [Re: RTLR 12]
      #5308308 - 07/08/12 01:43 PM

A very quick check before you dive into tearing stuff down would be to power on the mount, and before aligning or doing anything, command the RA for short slews east and west, then try commanding the DEC north and south the same way. Is it dead silent on the DEC motor, or does it make any sound?

If it's dead silent, the procedure in Stan's post above is what you're doing.

If it clicks or bumps or grunts, but doesn't turn, then check the leads to the motor and make sure no debris is in the gears. Or it may be the motor has died. As a last resort you can try pulling the motor out of the drive train and make see if it and the worm function normally apart.

If the motor runs at full speed but the axis doesn't move, look for a loose gear set screw. If the mount had this problem its accuracy in GOTO should have mysteriously dropped off shortly before the failure.

-Rich


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Astropin
super member


Reged: 08/30/07

Loc: Michigan
Re: CG5 declination motor just stopped working! new [Re: Starhawk]
      #5308991 - 07/08/12 09:19 PM

I'm having the exact same issue with my CG5. Waiting for parts to arrive.

In my case I know the DEC motor is good so now I just need to isolate the issue. Could be the DEC board but I don't think so. (Recently replaced) Could be the main power board (which is only $20). Could be the motor board as well but I don't think it is since that has already been replaced also.


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: Astropin]
      #5309138 - 07/08/12 11:40 PM

Well, here's a bit of an update. I got home very late from the star party last night and was too tired to unload all my gear out of the car. We had to go to my nephew's birthday party today. I figured I'd just leave my scope gear in the car and see about setting it up at the party for some solar. My nephew likes space stuff and was very excited when I offered to set it up.

Of course, I was fully expecting the DEC axis to be inoperable again. So I planned to just align the sun as best as I could and let the RA motor handle the tracking. Lo and behold, the DEC axis was working after setting it up. So, I'm very happy that it's not dead.

However, I am still concerned that there may be a growing problem. I've had several instances in the past couple months where my GoTo mount has just stopped working in one axis or another. If this continues to happen, I will definitely keep a log of which axis is acting up and the circumstances surrounding it.

To answer rdandrea's question, I received no error on the hand controller. The DEC axis just wouldn't move. I could not hear whether the motor was still running or not as there were many people talking around me. The hand controller continued to display the spinner indicating that it was still trying to slew, but it wasn't moving anywhere.


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rmollise
Postmaster
*****

Reged: 07/06/07

Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5309393 - 07/09/12 08:16 AM

The problem is almost always the declination cable. For starters, make sure it was plugged into the wrong jack. I've plugged mine into the autoguide port a time or two...which will not work.

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EFT
Vendor - Deep Space Products
*****

Reged: 05/07/07

Loc: Phoenix, AZ
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5309602 - 07/09/12 11:11 AM

As Rod pointed out, the DEC cable may be to blame. However, considering your extensive use recently, there is another possibility. The cables inside the RA motor housing run near and sometimes directly on top of the RA motor. With a lot of use the motor heats up and can burn the sheilding on the cables if they lie directly on the motor. I have seen this any number of times and the results can range from a dead axis to wild slewing. I would suspect that the cable that connects the motor board to the socket for the DEC cable is lying directly on the RA motor and is getting melted and may be completely through the shielding at this point. That can cause a short (sometime intermittent) that will cause the problems you are seeing.

If you do not see and obvious problem with the DEC cable, then you should remove the RA motor housing and take a look at the cables. If the cable is damaged, but not too bad, then some electrical tape will take care of the problem.


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: EFT]
      #5310077 - 07/09/12 04:12 PM

Rod, I verified I had the DEC cable in the correct port. Also, this particular DEC is relatively new. I was having some issues with the original DEC cable I got with the scope and replaced it last year. However, that does not mean the new one isn't going bad somehow, too.

Ed, I will definitely take the casing apart and check on the wires inside to be on the safe side. The DEC axis seems to be working fine again now. It operated flawlessly for several hours yesterday in the blazing sun as I had the scope set up for solar observing at my nephew's birthday party. So, it definitely seems like an intermittent issue, but I want to take care of it before it gets worse. BTW, thanks for a great product. I purchased the DIY Hypertune kit a year and a half ago and tuned up my mount real good. Works great now; nice and smooth with no more backlash!


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gmartin02
scholastic sledgehammer
*****

Reged: 04/11/05

Loc: Santa Clarita, CA
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5314993 - 07/12/12 08:24 PM

I have had this happen twice on my AS-GT in 4 years of ownership - I carefully took both motor casings apart, made sure the internal plugs were seated correctly, put it back together, and it worked great.

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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: gmartin02]
      #5316879 - 07/14/12 12:52 AM

Bugger! It happened to me again last night at a star party I was hosting in my neighborhood. The N/S buttons on my hand control wouldn't work, and the scope wouldn't slew in the DEC axis when selecting an object from a list. From the get-go this time. Last time, I was halfway through the evening before it went out on me. Last night, it didn't work at all.

I was able to manually point my scope and then engage the clutch on the RA access to keep it tracking. So the evening wasn't shot by any means. Just took a little longer and a little more fussin' to get things centered. Thank the stars for GLPs and finder scopes!

I'm definitely going to have to try and find time this weekend to take the casing off the DEC housing and see what's going on in there. I really hope it is an easy fix.


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mogur
scholastic sledgehammer
*****

Reged: 07/29/11

Loc: WI
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5318142 - 07/14/12 10:11 PM

I had this happen on a Vixen GP mount. In my case it was the wire to the Dec motor had pulled out from the plug. Apparently I got the mount turned too far around the axis and the wires were getting tighter every time I slewed it. Eventually they pulled away from the contacts inside the plug. I re-routed the wires, reconnected the wires to the plug and all is fine.

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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: mogur]
      #5342713 - 07/30/12 01:53 AM

Well, I need to go back to the drawing board. I was out at another public outreach event last night. My mount was working fine for a couple hours. Then the DEC motor stopped working again.

I thought I had it licked this time. A week or two ago, I had taken the housing off the DEC motor and checked to make sure all wires were okay. Everything seemed to be in good order. Lots of testing after that with the mount only didn't turn up any problems.

Now that I've gone back and re-read some of the suggestions here, I see that Ed recommended opening up the RA housing (not the DEC housing) to check that the wires from the motor board to the DEC connector are okay. I'll have to try that next. Also, I'm wondering if I should just go ahead and get a new DEC cable to be on the safe side. Another thought is whether it's possible the hand control could be having some type of problem that may cause this?


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mclewis1
Thread Killer
*****

Reged: 02/25/06

Loc: New Brunswick, Canada
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5343142 - 07/30/12 10:45 AM

Rob,

Unlikely it's the HC at all. If the HC can no longer talk to one of the motor controllers you'll get an No Response 16 or 17 error message. Just stopping is usually a cabling or problem with the motor itself.

I'd follow Ed's suggestions very closely, he probably has more experience working with the internals of the CG-5 than all the rest of us on this thread combined.


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: mclewis1]
      #5343347 - 07/30/12 12:34 PM

Yep, I'll probably be pulling it apart tonight and following Ed's directions exactly! Hoping it's something simple to fix.

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Astropin
super member


Reged: 08/30/07

Loc: Michigan
Re: CG5 declination motor just stopped working! *DELETED* new [Re: RobbW]
      #5344053 - 07/30/12 07:29 PM

Post deleted by David Pavlich

Edited by Astropin (07/30/12 07:30 PM)


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: Astropin]
      #5344508 - 07/31/12 12:37 AM

Pulled off the housing on both motors tonight. Inspected all wires and fittings. Could not find any evidence of the wires melting through or shorting. I had my battery pack hooked up and the mount powered up as I VERY carefully poked around. I kept testing the DEC controls on the HC to see if anything I did made a difference.

Once I pulled the DEC housing off, the DEC motor started working again. I'm thinking that maybe the wire connection on the back of the DEC socket jiggled loose somehow. I can't be sure as I don't remembered exactly what I did just prior to the DEC motor working again. Could have been a couple different things.

In any event, I grabbed a roll of electrical tape and taped down all the wire connections on the boards and sockets just to make sure that stay nice and secure. I sat in my kitchen/"workshop" and put the mount through its paces without the OTA or any counterweights. It works perfectly fine now. I won't know for sure if I finally fixed my problem until I get out in the field with my setup again for a few hours at a time. I really hope I got it taken care of this time.


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AcTpoHoM
member


Reged: 08/05/12

Loc: Bulgaria
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5352812 - 08/05/12 09:59 AM

Just wanted to share my experience as well. My dec motor stopped working a few weeks ago. I have found this thread and was following it with interest for eventual solution. Since the issue became clear a few days ago, I thought I should share my experience so it might help other CN members.

The reason for the issue with my (almost) brand new CG-5 dec motor was a loose connection in the RA casing, right behind the Dec port on the board. Note that it was not the connection of the Dec port to the board, but rather the connection of the cable to the board, behind the dec port. A little playing around and my dec motor works normally now. Note that visually there was absolutely nothing wrong, I just had to move the connector to the sides a few times before my mount started working again.

I guess the issue might re-occur, but I will think of a permanent solution if it comes to that.

Hope this helps, in case anyone stumbles on the same problem (God forbid).

Clear Skies!


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: AcTpoHoM]
      #5365807 - 08/13/12 01:52 AM

Grrr!!! Back to square one! I got my first chance to get out in the field with my scope after taking the mount apart a couple weeks ago. I thought I had fixed it then as I got the DEC motor to work just fine.

Tonight, I was volunteering at an outreach event/Perseids Meteor Shower Party. My DEC motor wouldn't work at all from the moment I powered up the mount. I have no idea where to go from here. Which part I should fiddle with, fix, or try to replace. From all accounts that I have read in my research on this problem, it could be anything from the DEC cable to the Power Board to the Motor Board to the wires rubbing on the housing to the DEC motor itself.

So, which part(s) do I start trying to replace first? I guess I'll start off with the cheapest ones and work my way up from there. I'll get the DEC cable, DEC board, and Power Board first. If those don't fix the problem, then I guess it's on to the more expensive items on the list. Let's see what happens. Keeping my fingers crossed!


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RTLR 12
Post Laureate
*****

Reged: 12/04/08

Loc: The Great Pacific NorthWest
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5365910 - 08/13/12 05:21 AM

Swapping the connectors for the motors on the MC board will test the MC board and DEC motor. If after swapping the connectors, and the DEC motor still does not work, it is not the MC board. (You will have to push the appropriate direction buttons) If the RA motor does not work, and the DEC motor now works, then the MC board is at fault.

Stan


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: RTLR 12]
      #5366643 - 08/13/12 03:04 PM

Thanks, Stan. That makes sense. My only problem with that is that whenever I take the housings off the motors, I'm always able to get the DEC motor working again. I don't know if it is just jiggling the wires/connectors around that makes it start working again or what?!?! Then I'll put the mount all back together and test it some more. The DEC motor continues to work and everything seems hunky dory. That is until the next time I actually take my scope out into the field. Then the DEC motor stops working for me again. In the past, it would operate properly for about an hour or so before it stopped working. Now, it just doesn't work from the get-go. I have no idea what to make of the situation.

The couple of times I've had the mount inside to take off the covers and inspect everything, I did not have my OTA on the mount. I just had the mount on the tripod while working on it. So, I don't know if it is the DEC motor really starting to go out and it is able to work fine with no load on it. And then once I put the OTA and counterweights on, it is too much for the the DEC motor. Or maybe there is something else loose somewhere, and packing up my mount and transporting it knocks that connection loose every time. I don't know. So, I am going to start by replacing the cheaper parts inside and then test it out under full load. If the DEC motor still cr@ps out on me, then I know it is either the motor itself or the Motor Board. At that point, I will perform your test to see if it is the motor or the board. We'll see!

Robb


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5374068 - 08/18/12 12:21 AM

UPS says replacement parts should be delivered this coming Tuesday. So, now my question is: does ordering mundane, internal repair parts invoke the astronomy curse? I would hope not. It's not like this is some new EP or other astro toy that I'm really excited to get. I'm just trying to fix my broken mount!

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cavefrog
Carpal Tunnel
*****

Reged: 11/11/08

Loc: loozyanna
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5374100 - 08/18/12 12:54 AM

I had an intermitent problem with my CG5ASGT. it finally went all out and stopped working completely (the dec).
turned out to be a broken wire. the wire was broken on the inside, but no damage to the insulation. I found it by stretching the wires.

Theo


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EFT
Vendor - Deep Space Products
*****

Reged: 05/07/07

Loc: Phoenix, AZ
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5374146 - 08/18/12 02:32 AM

Quote:

UPS says replacement parts should be delivered this coming Tuesday. So, now my question is: does ordering mundane, internal repair parts invoke the astronomy curse? I would hope not. It's not like this is some new EP or other astro toy that I'm really excited to get. I'm just trying to fix my broken mount!




Ordering the parts doesn't. Getting the mount fixed an working does.


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: EFT]
      #5380314 - 08/22/12 01:05 AM

All the small, inexpensive parts I ordered came in today. I completely set up my scope assembly this time including mount, tripod, OTA, and counterweights. I wanted to test if the DEC motor was simply wearing out and couldn't handle the full load anymore. Unfortunately, the DEC motor wouldn't work with or without the full load. So, it seems it was completely gone this time and had nothing to do with the weight of my scope and gear on the mount.

I proceeded to take all the plastic covers off the mount to perform more test before I started swapping out parts. I checked to make sure the RA motor still worked fine, which it did. I then disconnected the RA motor's wire connector from the Motor Control Board (MCB)and attached the DEC motor's wire connector in its place. Pressing the slew buttons on the hand control, I still could not get the DEC motor to operate. Connected the RA motor back up to the MCB, and it worked fine again. So, this is definitely making me lean more toward it being an issue with the DEC motor than with any of the control or power boards.

However, before I resort to ordering a new DEC motor, I want to replace the DEC port and Power Board with the new ones I bought, just to be sure. So, I swapped out those parts and hooked everything back up. Still, the DEC motor would not turn.

I then decided to start fiddling with all the wires to see if it was a damaged wire. While continuously holding down the North slew button, I started jiggling all the wire connections and bending all the wires. Nothing happened. Then I unplugged the encoder wire connector from the bottom of the DEC motor and plugged it back in. Suddenly, I got a very brief but very fast slew from the DEC motor. And then I got the "No Response 17" error on the Hand Control.

I powered the mount off and back on again to clear the error message. Tried slewing the DEC motor again and the same thing happened. Very fast but short movement from the DEC motor followed by the "No Response 17" message. I powered off/on my mount again, and this time I removed the cap from the encoder wheel on the bottom of the DEC motor. After removing the cap, I was able to continuously slew the DEC motor.

However, something was definitely wrong with it. The slew rate was exceptionally fast. Much faster than I'd ever seen it before, and the motor was extremely loud. I tried adjusting the slew rate from 9 down to 5, but the DEC motor still moved at the same ultra-fast speed regardless of what slew rate I set. The RA motor operated at the correct speed for whatever slew rate I set, but the DEC motor stayed in afterburner mode. Not only that, but the DEC motor wouldn't stop immediately after I let go of the slew button. It would continue to slew for 2-3 seconds before finally stopping.

I put the cap back on the encoder wheel and kept fiddling with its wire connection to see if that was the culprit. Unfortunately, messing with the wires didn't seem to affect anything. After running the DEC motor in this super fast rate for a bit, it started throwing up the "No Response 17" error again. I could press "UNDO" to clear the error, but then the DEC motor wouldn't work anymore. The RA motor still worked perfectly fine this entire time. After power cycling the mount again, the DEC motor is now giving the "No Response 17" error pretty much every time and is only operating in the super-fast slew rate intermittently (maybe once in every 3-4 tries after power cycling).

After messing with this for about 1.5 hours, I gave up. I cleaned up all my parts and put my mount back together. I resolved to simply order a new DEC motor as everything I tested out seems to point to it being the problem.

I placed my order with Celestron tonight and will patiently (or not) await its delivery. I can only hope that the new DEC motor will finally clear away all my problems, and I can have a properly working CG5 mount again.

Keeping my fingers crossed!


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RTLR 12
Post Laureate
*****

Reged: 12/04/08

Loc: The Great Pacific NorthWest
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5380439 - 08/22/12 03:35 AM

Did you check the air gap on the encoder wheel? The air gap between the optical pick up on the encoder and the surface of the encoder wheel should be set at about .035" to .045". Be very careful when setting or measuring the air gap as the encoder wheel is made of glass and is fragile.

Stan


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: RTLR 12]
      #5381137 - 08/22/12 01:58 PM

No, I did not, Stan. I have no tools for making small measurements like that. Besides, I've fooled around with this thing long enough for my liking. I just went ahead and ordered a new DEC motor. When it comes in, I will install it and hope that all my issues go away!

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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5392433 - 08/28/12 11:30 PM

New DEC motor arrived via UPS today. After the kids went to bed, I took the covers off my mount and replaced the motor. The difference and improvement in its performance was immediately obvious. I put the covers back on and loaded the mount up with OTA and counterweights. After 30 minutes of testing, everything is whirring like clockwork!

Turns out there is one small problem though. When I was disassembling my scope and moving everything out of my kitchen, I found my power supply to be leaking an unknown liquid. Closer inspection revealed it to be sulfuric acid leaking out of the battery. Yeesh! Another part needing replacement!


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RobbW
sage


Reged: 02/09/10

Loc: Elgin, IL
Re: CG5 declination motor just stopped working! new [Re: EFT]
      #5397170 - 08/31/12 06:49 PM

Quote:

Quote:

UPS says replacement parts should be delivered this coming Tuesday. So, now my question is: does ordering mundane, internal repair parts invoke the astronomy curse? I would hope not. It's not like this is some new EP or other astro toy that I'm really excited to get. I'm just trying to fix my broken mount!




Ordering the parts doesn't. Getting the mount fixed an working does.




I apologize to everyone for fixing my mount and replacing the battery in my power supply. I had no idea it would result in Issac socking us in for the whole weekend!


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ptsouth97
member


Reged: 03/04/12

Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5487621 - 10/24/12 08:49 PM

My CG-5's declination motor stopped working, as well. After reading through this thread, I took the plastic casing off of the RA and declination drives and started poking around. At this point, I was still able to run the RA drive. Then, everything stopped working. I quickly realized that the red light on the power cord from my Celestron Power tank was no longer glowing. I disassembled it and found a blown fuse. I took a trip to an auto part shop and bought a 5 pack of replacement fuses. I popped a new one in and tested it for continuity and everything was fine. However, as soon as I plugged it into the scope, the fuse blew again. Any ideas here? If something is making contact and shorting out somewhere, I sure don't see it.

Thanks,
Blake


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RTLR 12
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5487797 - 10/24/12 10:51 PM

Check the wires to the motor. They have been known to rub on the motor cases and short out.

Stan


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jchoy46
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Re: CG5 declination motor just stopped working! new [Re: RTLR 12]
      #5488185 - 10/25/12 08:24 AM

also stop using the on/ off switch... they have gremlins and short out the scope!

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: RTLR 12]
      #5488188 - 10/25/12 08:30 AM

Thanks for the suggestion. Visually, the wires look ok and the connections seem tight. I'm showing a closed circuit from the motor board to the motors with a continuity test. Every time I put a new fuse into my power cord from the power tank, it blows almost instantly. I have power tanks/power cords and the same thing happens to both. Any other ideas?

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: jchoy46]
      #5488190 - 10/25/12 08:31 AM

By stop using, I assume you mean just leave it on? I can handle that but would need an explanation for anything more complicated.

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5488205 - 10/25/12 08:44 AM

I just tried replacing the fuse and plugging in the power cord to the power board with the power switch on. Same result: blown fuse immediately.

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rmollise
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5488225 - 10/25/12 09:02 AM

By "closed circuit," you mean a dead short? For starters, examine the circuit board for any signs of burned components.

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: rmollise]
      #5488569 - 10/25/12 12:36 PM

Sorry if I'm using the wrong terminology as I'm new to this. When I said closed circuit, I was just saying I put the leads from the continuity tester on both sides of a particular element and the bulb on the tester lit up. I thought that meant the current was flowing through so the circuit was "closed."

I don't see anything on the circuit board that looks burned. How obvious should it be? One thing I noticed is that some of the wires have a slight yellow discoloration to them. However, again, I'm showing that they are still working with the continuity test. Maybe I'm doing something wrong?


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rmollise
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5488779 - 10/25/12 02:52 PM

What I would advise, other than the usual...check can clean all connections, is have a buddy with some electronics experience check things out. If you are getting continuity between an input and an output on the PCB, something is badly wrong (unless what you are checking chassis ground or something...

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jchoy46
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Re: CG5 declination motor just stopped working! new [Re: rmollise]
      #5489935 - 10/26/12 10:05 AM

i just leave the switch on and unplug the power cord to turn it off and when i want to use it, i just plug it in. CG%'s have a known bug with the power switches. So I dont use mine.

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: jchoy46]
      #5491520 - 10/27/12 11:04 AM

Yeah, that's what I tried. I ordered a new power board and hopefully that will do the trick.

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5505589 - 11/05/12 03:19 PM

So the new power board arrived and I swapped it out with the old one. The fuse blew again in about 1 second and this time I got the tell-tale plume of smoke and smell of crispy circuits. There was no such indication of burning on the old power board. Assuming the new board was ok to begin with, am I looking at a problem with the power cord running from the battery to the mount? I was reading on another thread that the Celestron cords can be faulty and can be replaced by one from Radioshack. I don't think it's the battery,because the battery is supplying power just fine to my Nexstar 4se.

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rmollise
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Re: CG5 declination motor just stopped working! new [Re: ptsouth97]
      #5505629 - 11/05/12 03:55 PM

If you can't do so yourself, find a buddy with electronics/electrical experience and have him/her check your cable, connectors, etc.

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nebultick
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Re: CG5 declination motor just stopped working! new [Re: RobbW]
      #5506760 - 11/06/12 11:53 AM

probably completely unrelated but if this happens to anyone else. My dec motor on my super polaris started to die while imaging last night. I used a battery pack with 8 D cells. Well they were dead, the RA motor would still move just fine but the Dec would be all kinds of funky. I hooked up it to a 12V supply and it worked fine. I'm assuming RA motor get the power first since it is always moving.

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TopherTheME
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Re: CG5 declination motor just stopped working! new [Re: nebultick]
      #5506795 - 11/06/12 12:18 PM

I would grab a DMM and start measuring. One thing to keep in mind is that the Dec axis binds very easily on the CG-5. If a motor is stuck and can't rotate it becomes a resistor and will pull a lot of current. Make sure your DEC axis is free by removing/loosening the Dec motor and worm gear.

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ptsouth97
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Re: CG5 declination motor just stopped working! new [Re: TopherTheME]
      #5528411 - 11/19/12 05:10 PM

Ok, I have checked for continuity. Is there a schematic somewhere that shows what values I should be getting with a DMM? I searched the Internet with no luck.

Also, how do I tell how loose the dec axis should be?


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