Re: 900 mount spurious RA motor slewing and stall
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Actually, I had a similar issue happen with my Parallax 250 mount which uses the AP GOTO system. Auto-slews upon resuming from Park and/or touching any handl paddle buttons or with SkyX. After much time with George and Joe (Parallax) on the phone (bothe were very helpful), and swapping the RA & Dec motor/encoders around, it turned out to be a failed RA motor/encoder. The fix was easy, a new motor/encoder with AP installing an anti-static circuit board too. Trouble is it took a couple of months to get the servo motor from Maxum, routed through Parallax to AP then back to Joe then to me. Both shops were great! The swap out took all of 5 minutes, then everything worked fine. Certainly not a cheap fix but a straight forward one. It's been a few years but, as I recall, the bum motor/encoder also messed with the DEC.
On Fri, Nov 27, 2020 at 10:57 AM <kensablinsky@...> wrote:
Hey everyone, longtime AP900 user and lurker, with a problem that just cropped up. I'm the original owner of a 900 mount for around 20 years now, and recently upgraded to the CP4 (with new motor cables and new 2-pin power cable). It's been working pretty flawlessly with the CP4 and APCC pro for months, but all of a sudden is giving me a motor movement and stall problem. Yesterday it would slew East/West OR North/South fine, but when both motors slewed together at any slewing speed, the motors sounded strained and sped up and slowed down in a jerky fashion. Sounds like a power problem I thought, so I moved to a different power source (Powerwerx 30 amp supply, nothing else plugged into it, volt meter showing 14v output). Same problem. Today, it's much worse -- as soon as I boot up APCC Pro and click Initialize, the RA axis slews 10-15 degrees (OTA moving to the west) and the motors stall. So I unplugged everything from the CP4 except for the motor cable, and pulled out my old AP hand controller, to make sure the problem wasn't coming from an external source.