Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

C8 RA Drive Backwards

This topic has been archived. This means that you cannot reply to this topic.
7 replies to this topic

#1 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 17 March 2004 - 05:56 AM

My newly obtained C8 with standard RA drive is running in backwards direction. I've tried to change the direction as directed in the manual, holding both Dec hand controller buttons down while powering it up, but no dice. It's only on battery power now. Will I fry the electronics if I merely reverse the polarity of the battery? I will eventually go to a 12 VDC power source but want to iron out this direction problem first. Tnx in advance, Phil

#2 Don W

Don W

    demi-god

  • *****
  • Administrators
  • Posts: 22831
  • Joined: 19 May 2003

Posted 17 March 2004 - 07:47 AM

Need much more info since there have been quite a few different versions of the C8 using a lot of different drive systems.

#3 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 17 March 2004 - 08:51 AM

Will I fry the electronics if I merely reverse the polarity of the battery?

Yes, you will fry your electronics. Or if you're lucky, you'll just blow a fuse or it just won't work at all. I can't imagine any DC-powered drive system that changes direction according to polarity of input power.

#4 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 17 March 2004 - 01:55 PM

Attached is a Word document of the three pages from the manual which describes the drive, how to change it's direction, and has a picture.

Attached Files



#5 Don W

Don W

    demi-god

  • *****
  • Administrators
  • Posts: 22831
  • Joined: 19 May 2003

Posted 17 March 2004 - 04:15 PM

I think I found your answer. You can switch the drive for use in the southern hemisphere. Check your manual for this section:

[quote]
NORTHERN/SOUTHERN HEMISPHERE OPERATION

When using your Celestar 8 in the southern hemisphere, there is a need to reverse the direction of the R. A. motor. In previous telescopes this was accomplished by installing a reversed motor. Now, the direction the drive motor moves the telescope is within the control of the user. Changing from northern hemisphere to southern hemisphere requires changing the polarity of the drive motor. To do this:

1. You need to purchase the optional hand controller.

2. With the power turned off, press down and hold the up and down buttons simultaneously.

3. Turn the power switch on (keep holding the buttons down).

4. In one or two seconds the red (LED) will blink. This will indicate the telescope is set for the southern hemisphere.

5. Keep the hand controller plugged in at all times. If you unplug the unit, it will default back to northern hemisphere operation.

The direction of the drive motor is now reversed and will work in the opposite hemisphere. [unquote]

#6 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----
  • topic starter

Posted 17 March 2004 - 05:00 PM

No, you see that is the problem. In the default or no hand controller plugged in position, the RA drive is turning backwards, i.e. the scope will turn CCW when looking at the scope from the north looking south. It should turn CW in the northern hemi. correct? When I try the reversing fix as stated in the manual, nothing happens. The LED light doesn't flash, nada. So that is the problem. Phil

#7 Don W

Don W

    demi-god

  • *****
  • Administrators
  • Posts: 22831
  • Joined: 19 May 2003

Posted 17 March 2004 - 05:06 PM

Oh......sorry. That's not good. You might have to give Celestron a call.

#8 Rusty

Rusty

    ISS

  • *****
  • In Memoriam
  • Posts: 22761
  • Joined: 06 Aug 2003

Posted 17 March 2004 - 09:23 PM

If it slews in the correct direction, it's set up for the southern hemisphere. If not, the RA drive motor is wired backwards.


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics